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  • 1. Aberg, B
    et al.
    Koul, B L
    Liska, J
    Brodin, L A
    KTH, School of Technology and Health (STH).
    Landou, C
    Delayed left ventricular free wall rupture complicating coronary artery bypass surgery. A case report.1985In: Scandinavian journal of thoracic and cardiovascular surgery, ISSN 0036-5580, Vol. 19, no 3, p. 273-7Article in journal (Refereed)
    Abstract [en]

    Rupture of the left ventricular free wall is a not uncommon life-threatening complication of acute myocardial infarction and after prosthetic mitral valve replacement. To our knowledge, no case of left ventricular rupture after coronary artery bypass surgery has been reported. A case is now described in which coronary artery bypass grafting was complicated by delayed rupture, which was successfully repaired. Different etiologic factors are discussed, but the cause considered most likely was trauma from elevation of and traction on the heart in exposure of its posterior aspect.

  • 2. Andersson, L.
    et al.
    Lagerstrand, L.
    Thorne, A.
    Sollevi, A.
    Brodin, Lars-Åke
    Odeberg-Wernerman, S.
    Effect of CO2 pneumoperitoneum on ventilation-perfusion relationships during laparoscopic cholecystectomy2002In: Acta Anaesthesiologica Scandinavica, ISSN 0001-5172, E-ISSN 1399-6576, Vol. 46, no 5, p. 552-560Article in journal (Refereed)
    Abstract [en]

    Background: Previous studies have shown that pneumoperitoneum transiently reduces venous admixture as assessed by a calculation based on the shunt formula, and increases arterial oxygen tension (PaO2) in patients without heart or lung disease. The aim of the present study was to further explore the relationship between ventilation-perfusion ((V) over dot (A)/(Q) over dot) before and during pneumoperitoneum by using the multiple inert gas technique. Methods: Nine patients without heart or lung disease (ASA I), with a mean age of 42 years, scheduled for laparoscopic cholecystectomy were included. After premedication and induction of anaesthesia, radial artery and pulmonary artery catheters were introduced percutaneously. The (V) over dot (A)/(Q) over dot relationships were evaluated by the multiple inert gas elimination technique before and during pneurnoperitoneum to obtain a direct measure of the pulmonary shunt. Results: Induction of pneumoperitoneum decreased the pulmonary shunt from 5.8 (4.5) to 4.1 (3.2)% (P<0.05) and increased PaO2 from 21.7 (5.9) to 24.7 (4.8) kPa (P<0.01). During surgery, the shunt increased from 3.2 (2.8) to 5.2 (3.4)% to the same level as before pneumoperitoneum induction. No area with low (V) over dot (A)/(Q) over dot was seen. Dead space ventilation amounted to 20.0 (1.2)% in the supine position and did not change during the investigation. Conclusions: In patients without heart or lung disease, pneumoperitoneum at an intra-abdominal pressure level of 11-13 mmHg- causes a transient reduction of the pulmonary shunt. The mechanisms underlying the present finding remain to be elucidated.

  • 3.
    Bjällmark, Anna
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Gustafsson, U
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Waldenström, A
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    A system to quantify and visualize ventricular rotation pattern of the heart2009Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    Different modalities have been used to describe the rotational motion of the ventricles of the heart and studies have indicated LV twist to be an additional integral component in LV function. So far, only amplitudes and timings of rotation have been reported, whereas no method is available to fully describe the rotation pattern of the ventricles. The object of the present application is to achieve a system that presents a novel way to quantify and visualize the ventricular rotation pattern of the heart. We present a novel method that assesses and describes the rotation pattern by calculating the rotation axis of the ventricle. Non- invasive image acquisition is required to collect rotation values from different positions of the myocardium. Thereafter, a kinematic model of a ventricle is constructed to determine the rotation planes at different levels of the heart. The motion of the rotation planes are visualized by plotting the normal vectors of the planes over time, i.e. the rotation axis of the planes. This new method is different to all other methods used today for assessing cardiac function, as it does not describe the amplitude of a motion but the relationship in motion between different parts within a ventricle. Preliminary results indicate that the rotation axis is more sensitive to changes in the rotation pattern than conventional measurements of ventricular rotation. This new method could be used for early detection of cardiac diseases and for selection of patients for and optimization of cardiac resynchronization therapy.

  • 4.
    Bjällmark, Anna
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nowak, Jacek
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Hayashi, Shirley
    Mazza do Nascimento, Marcelo
    Riella, Miquel
    Seeberger, Astrid
    Effects of hemodialysis on the cardiovascular system: Quantitative analysis using wave intensity wall analysis and tissue velocity imaging2010In: Heart and Vessels, ISSN 0910-8327, E-ISSN 1615-2573Article in journal (Refereed)
    Abstract [en]

    Cardiovascular disease is the leading cause of death in patients with end stage renal disease (ESRD). The aim of this study was to investigate the changes in cardiovascular function induced by a single session of hemodialysis (HD) by the analysis of cardiovascular dynamics using wave intensity wall analysis (WIWA) and of systolic and diastolic myocardial function using tissue velocity imaging (TVI). Grey-scale cine loops of the left common carotid artery, conventional echocardiography and TVI images of the left ventricle were acquired before and after HD in 45 patients (17 women, mean age 54) with ESRD. The WIWA indexes, W1 preload-adjusted W1, W2 and preload-adjusted W2, and the TVI variables, isovolumic contraction velocity (IVCV), isovolumic contraction time (IVCT), peak systolic velocity (PSV), displacement, isovolumic relaxation velocity (IVRV), isovolumic relaxation time (IVRT), peak early diastolic velocity (E’) and peak late diastolic velocity (A’), were compared before and after HD. The WIWA measurements showed significant increases in W1 (p < 0.05) and preload-adjusted W1 (p < 0.01) after HD. W2 was significantly decreased (p < 0.05) after HD, whereas the change in preload-adjusted W2 was not significant. Systolic velocities, IVCV (p < 0.001) and PSV (p < 0.01), were increased after HD, whereas the AV-plane displacement were decreased (p < 0.01). For the measured diastolic variables, E’ was significantly decreased (p < 0.01) and IVRT was significantly prolonged (p < 0.05), after HD. A few correlations were found between WIWA and TVI variables. The WIWA and TVI measurements indicate that a single session of HD improves systolic function. The load dependency of the diastolic variables seems to be more pronounced than for the systolic variables. Preload-adjusted wave intensity indexes may contribute in the assessment of true LV contractility and relaxation.

  • 5.
    Bjällmark, Anna
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Winter, Reidar
    Westholm, Carl
    Jacobsen, Per
    Velocity tracking - a novel method for quantitative analysis of longitudinal myocardial function2007In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 20, no 7, p. 847-856Article in journal (Refereed)
    Abstract [en]

    Doppler tissue imaging is a method for quantitative analysis of longitudinal myocardial velocity. Commercially available ultrasound systems can only present velocity information using a color Dopplerbased overlapping continuous color scale. The analysis is time-consuming and does not allow for simultaneous analysis in different projections. We have developed a new method, velocity tracking, using a stepwise color coding of the regional longitudinal myocardial velocity. The velocity data from 3 apical projections are presented as static and dynamic bull's-eye plots to give a 3-dimensional understanding of the function of the left ventricle. The static bull's-eye plot can display peak systolic velocity, late diastofic tissue velocity, or the sum of peak systolic velocity and early diastolic tissue velocity. Conversely, the dynamic bull's-eye plot displays how the myocardial velocities change over one heart cycle. Velocity tracking allows for a fast, simple, and hituitive visual analysis of the regional longitudinal contraction pattern of the left ventricle with a great potential to identify characteristic pathologic patterns.

  • 6.
    Bjällmark, Anna
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Shahgaldi, Kambiz
    Lind, Britta
    KTH, School of Technology and Health (STH).
    Winter, Reidar
    Brodin, Lars-Ake
    KTH, School of Technology and Health (STH), Medical Engineering.
    Differences in myocardial velocities during supine and upright exercise stress echocardiography in healthy adults2009In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 29, no 3, p. 216-223Article in journal (Refereed)
    Abstract [en]

    Tissue Velocity Imaging (TVI) is a method for quantitative analysis of longitudinal myocardial velocities, which can be used during exercise and pharmacological stress echocardiography. It is of interest to evaluate cardiac response to different types of stress tests and the differences between upright and supine bicycle exercise tests have not been fully investigated. Therefore, the aim of this study was to compare cardiac response during supine and upright exercise stress tests. Twenty young healthy individuals underwent supine and upright stress test. The initial workload was set to 30 W and was increased every minute by a further 30 W until physical exhaustion. Tissue Doppler data from the left ventricle were acquired at the end of every workload level using a GE Vivid7 Dimension system (> 200 frames s(-1)). In the off-line processing, isovolumic contraction velocity (IVCV), peak systolic velocity (PSV), isovolumic relaxation velocity (IVRV), peak early diastolic velocity (E') and peak late diastolic velocity (A') were identified at every workload level. No significant difference between the tests was found in PSV. On the contrary, E' was shown to be significantly higher (P < 0.001) during supine exercise than during upright exercise and IVRV was significantly lower (P < 0.001) during supine exercise compared to upright exercise. Upright and supine exercise stress echocardiography give a comparable increase in measured systolic velocities and significant differences in early diastolic velocities.

  • 7.
    Bjällmark, Anna
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Peolsson, Michael
    KTH, School of Technology and Health (STH).
    Shahgaldi, Kambiz
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nowak, Jacek
    Ultrasonographic strain imaging is superior to conventional non-invasive measures of vascular stiffness in the detection of age-dependent differences in the mechanical properties of the common carotid artery2010In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 11, no 7, p. 630-636Article in journal (Refereed)
    Abstract [en]

    Aims: Elastic properties of large arteries have been shown to deteriorate with age and in the presence of atherosclerotic vascular disease. In this study, the performance of ultrasonographic strain measurements was compared to conventional measures of vascular stiffness in the detection of age-dependent differences in the elastic properties of the common carotid artery.

    Methods and results: In 10 younger (25-28 years, 4 women) and 10 older (50-59 years, 4 women) healthy individuals, global and regional circumferential and radial strain variables were measured in the short-axis view of the right common carotid artery using ultrasonographic two-dimensional (2D) strain imaging with recently introduced speckle tracking technique. Conventional elasticity variables, elastic modulus (Ep) and β stiffness index, were calculated using M-mode sonography and non-invasive blood pressure measurements. Global and regional circumferential systolic strain and strain rate values were significantly higher (p < 0.001, p < 0.01 for regional late systolic strain rate) in the younger individuals, whereas the values of conventional elasticity variables in the same group were lower (p < 0.05). Among all strain and conventional elasticity variables, principal component analysis and its regression extension identified only circumferential systolic strain variables as contributing significantly to the observed discrimination between the younger and older age groups.

    Conclusion: Ultrasonographic 2D-strain imaging is a sensitive method for the assessment of elastic properties in the common carotid artery, being in this respect superior to conventional measures of vascular elasticity. The method has potential to become a valuable non-invasive tool in the detection of early atherosclerotic vascular changes.

  • 8. Bratel, T.
    et al.
    Lagerstrand, L.
    Brodin, Lars-Åke
    Department of Clinical Physiology, Huddinge University Hospital, Stockholm, Sweden.
    Nowak, J.
    Randmaa, I.
    Ventilation/perfusion ratios in pulmonary arterial hypertension: Effects of IV and inhaled prostacyclin derivatives2005In: Chest, ISSN 0012-3692, E-ISSN 1931-3543, Vol. 128, no 6, p. 615S-616SArticle in journal (Refereed)
  • 9. Bratel, Tomas
    et al.
    Lagerstrand, Lars
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska University Hospital, Huddinge.
    Nowak, Jacek
    Randmaa, Ivar
    Ventilation-perfusion relationships in pulmonary arterial hypertension: Effect of intravenous and inhaled prostacyclin treatment2007In: Respiratory Physiology & Neurobiology, ISSN 1569-9048, E-ISSN 1878-1519, Vol. 158, no 1, p. 59-69Article in journal (Refereed)
    Abstract [en]

    In seven patients with idiopathic or secondary pulmonary arterial hypertension (PAH), ventilation-perfusion (V-A/Q) relationships were measured during a right heart catheterization using the multiple inert-gas elimination technique before and during intravenous infusion with epoprostenol (EPO), and following 5 months of 20 mu g inhaled iloprost taken three times daily (ILO). Pre-treatment pulmonary vascular resistance (PVR) was 9.3 +/- 5.0 mmHg/l/min and the dispersion of perfusion and ventilation for V-A/Q-ratios was increased. EPO reduced PVR by 20%, and increased cardiac output, shunt, and mixed venous oxygenation (Sv(O2)) The arterial oxygen tension (Pa-O2) remained unchanged. Basal central haemodynamics did not change after 5 months of ILO. Fifteen minutes after ILO, PVR decreased by 20%, and the shunt, Sv(O2), and Pa-O2 remained unaltered. Conclusions: In secondary PAH with normal lung volumes, significant V-A/Q mismatching occurred. The PVR was reduced to a similar degree during EPO and after ILO, but only EPO increased the shunt and Sv(O2). EPO and ILO did not significantly affect the Pa-O2.

  • 10.
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska University Hospital.
    Tissue Doppler, a fundamental tool for parametric imaging2004In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 24, no 3, p. 147-155Article in journal (Refereed)
    Abstract [en]

    Tissue Doppler has been used for clinical applications since 1989. It has been developed from a pulsed Doppler acquisition tool towards a method where extraction of velocities can be performed from colour-coded images. This has introduced a further development into different forms of parametric images describing different myocardial functions as colour-coded information, like deformation imaging, motion imaging and phase imaging. The technical requirements have been established with temporal requirements of frame rates in acquisition exceeding 100 frames s(-1). The most powerful application of the tissue Doppler technique today is perhaps to quantify the myocardial functional reserve, during stress echocardiography, making the method applicable to diagnose the presence of coronary disease with an accuracy exceeding that of nuclear and other non-invasive techniques. The method has also great potential for future developments with introduction of more regional measuring variables.

  • 11.
    Brodin, Lars-Åke
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering. Karolinska Universitetssjukhuset Huddinge, Sweden.
    Boman, K.
    Dahlström, U. L. F.
    Hagerman, I.
    Willenheimer, R.
    Ekokardiografi förfinar diagnostiken vid hjärtsvikt2007In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 104, no 34, p. 2338-2344Article in journal (Refereed)
  • 12.
    Brodin, Lars-Åke
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Elmqvist, H
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Global and local detection of blood vessel elasticity2006Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The present invention is a non-invasive analysis system for detection of global and local blood vessel elasticity. The analysis system comprises two subsystems where subsystem 1 is data collecting unit and subsystem 2 is an analysis unit. The data collecting unit comprises one or many non-invasive image generating systems, or the data collecting system makes the registration possible of movement parameters that quantifies the dynamics of the blood vessel wall in longitudinal and radial directions. Subsystem 2 performs Wave Intensity Analysis which is an analysis method using co-related parts of the circulation system by measuring the intensity change (dl) of the blood vessel during a heart cycle. The intensity change is calculated as the product of the pressure derivate and the flow velocity derivate. In subsystem 2 the changes of pressure and flow are approximated by the deformation velocity or velocity of the radial and longitudinal direction, respectively. By calculating time constants and amplitudes of the intensity change graph a measure is obtained of the local and global elasticity of the blood vessel and atherosclerotic constrictions of arterial vessels may then be identified at an early stage.

  • 13.
    Burmeister, Jens
    et al.
    University of Dresden, Germany.
    Lindh, Thomas
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Orhan, Ibrahim
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Contention-Based Wireless Sensor Networks: A case study for ambient assisted living2010In: Active Ageing, Smart Solutions, New Markets, 2010Conference paper (Refereed)
    Abstract [en]

    Wireless personal area networks have emerged as an important communication infrastructure in areas such as at-home healthcare and home automation, independent living and assistive technology. Initiatives towards interoperability and standardization are taken by several players. Zigbee Alliance has launched a profile for “Zigbee wireless sensor applications for health, wellness and fitness” [1]. The Continua Health Alliance promotes “an interoperable personal healthcare ecosystem”. They have published “design guidelines for the telehealth ecosystem” including the interface to personal area network health devices and electronic health record devices ([2], [3]). These examples show that wireless personal area networks, including body sensor networks, are becoming more mature and are considered to be a realistic alternative as communication infrastructure for demanding services. However, to transmit vital sign parameters from ECGs, pulse-oximeters, EEGs etc in wireless networks is also a challenge, especially if multiple sensors compete for access. Contention-based access networks offer simplicity and utilization advantages, but the drawback is unpredictable performance due to loss of transmitted packets.

    We have used the SHIMMER wireless sensor platform developed at Intel [4] in the living lab at the Centre for Health and Building at KTH in a case study to identify and evaluate performance problems. The full-scale living lab consists of two apartments especially equipped with modern technique for healthcare at home and assisted living.

    Our paper focuses on continuous monitoring of the heart activity using a wireless ECG based on the wireless personal area network (WPAN) standard IEEE 802.15.4. Results from performance tests in the living lab will be presented e.g. influence of equipment such as micro wave ovens. Since contention-based wireless access has no guarantees for the quality of the delivered service it is interesting to determine to what extent the received ECG signal is sensitive to loss of information. We have recorded ECG signals as well as emulated packet loss in existing ECG records from official databases. The result of two cardiologists´ assessment of ECGs with different loss ratio levels and patterns will be reported in the paper. One interesting conclusion is that a diagnosis is fully possible for ECGs with packet loss ratio up to at least 5%. This project is part of research at the School of Technology and Health at KTH.

  • 14. Carlsson, Camilla
    et al.
    Söderqvist, Emil
    KTH, Superseded Departments, KTH Syd.
    Brodin, Lars-Åke
    Källner, Göran
    Hultman, Jan
    Elmqvist, Håkan
    Saha, Samir
    Initial experience with a thin single segment pressure and conductance catheter for measurement of left ventricular volume2001In: Annual Reports of the Research Reactor Institute, Kyoto University, 2001, p. 103-106Conference paper (Refereed)
    Abstract [en]

    Aims: To evaluate a thin and soft multifunctionalcatheter for the simultaneous real time monitoring of leftventricular volume and pressure with special consideration toside elTects such as interference with normal cardiacelectrophysiology.Methods and results: In four pigs, pressure and volumewere simultaneously recorded by using the thin single segmentpressure and conductance catheter. Measurements were doneunder varied cardiac conditions: at baseline, during preloadreduction and afterload Increase. Volumes were calibrated withintracardiac ultrasound measurements. During preloadreduction the pressure and volume decreased as expected. Acautious afterload increase resulted in a corresponding pressureand volume increase, the maximum of the pressure curvechanged from early to late. Both SV and EDV increased. Thevery few arrhythmias were mainly caused by surgicalinterference.Conclusion: The present study demonstrates that our thinsingle segment conductance catheter for the simultaneousmeasurement of LV volume and pressure has a performancethat warrants further development with the goal to make themethod available for human use. In particular, the catheter didnot cause any arrhythmias.

  • 15. Carlsson, Lars
    et al.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Laaksonen, Marko S.
    Berglund, Bo
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Holmberg, Hans-Christer
    Enhanced systolic myocardial function in elite endurance athletes during combined arm-and-leg exercise2011In: European Journal of Applied Physiology, ISSN 1439-6319, E-ISSN 1439-6327, Vol. 111, no 6, p. 905-913Article in journal (Refereed)
    Abstract [en]

    The aim here was to employ color tissue velocity imaging (TVI), to test the hypothesis that highly trained endurance athletes exhibit enhanced systolic function of the left ventricular (LV) myocardium both at rest and during combined arm-and-leg exercise in comparison with untrained subjects. For each of the ten elite male (EG) and ten matched control participants (CG), LV dimensions and systolic function were assessed at rest using echocardiography. Subsequently, these subjects exercised continuously on a combined arm-and-leg cycle ergometer for 3 min each at 50, 60, 70, 80, 90 and 100% of VO2max. Oxygen uptake, heart rate, systolic blood pressure (SBP) and peak contraction systolic velocities of the LV myocardium (PSV) were recorded in the end of each level. At rest, the trained and untrained groups differed with respect to LV dimensions, but not systolic function. At 60-100% VO2max, the EG group demonstrated both higher PSV and SBP. The observation that the EG athletes had higher PSV than CG during exercise at 60-100% VO2max, but not at rest or at 50% of VO2max, suggested an enhanced systolic capacity. This improvement is likely to be due to an enhanced inotropic contractility, which only becomes apparent during exercise.

  • 16. Chan, M. C.
    et al.
    Gaballa, M.
    Williams, R.
    Sivakumaran, S.
    O'Reilly, K.
    van der Linden, J.
    Brodin, Lars-Åke
    Hui, W.
    Tissue Doppler guided optimization of A-V and V-V delay of biventricular pacemaker improves response to cardiac resynchronization therapy in heart failure patients2005In: Journal of the American College of Cardiology, ISSN 0735-1097, E-ISSN 1558-3597, Vol. 45, no 3, p. 274A-274AArticle in journal (Other academic)
  • 17. Chan, M. C. Y.
    et al.
    Gaballa, M.
    Willliams, R.
    Sivakumaran, S.
    O'Reilly, K.
    Van der Linder, J.
    Brodin, Lars-Åke
    Karolinska Institutet.
    Hui, W.
    Tissue Doppler guided optimization of A-V and V-V delay of biventricular pacemaker improves response to cardiac resynchronization therapy in heart failure patients2004In: Journal of Cardiac Failure, ISSN 1071-9164, E-ISSN 1532-8414, Vol. 10, no 4, p. S72-S72Article in journal (Other academic)
  • 18. Dahlström, U. L. F.
    et al.
    Boman, K.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Hagerman, I.
    Willenheimer, R.
    Behandling vid hjärtsvikt och bevarad systolisk funktion2007In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 104, no 34, p. 2348-2350Article in journal (Refereed)
  • 19. Dellgren, G.
    et al.
    Eriksson, M. J.
    Brodin, Lars-Åke
    Radegran, K.
    Eleven years' experience with the Biocor stentless aortic bioprosthesis: clinical and hemodynamic follow-up with long-term relative survival rate2002In: European Journal of Cardio-Thoracic Surgery, ISSN 1010-7940, E-ISSN 1873-734X, Vol. 22, no 6, p. 912-921Article in journal (Refereed)
    Abstract [en]

    Objective. The long-term durability and hemodynamics of stentless valves are largely unknown. Our aim was to prospectively investigate long-term hemodynamic function and clinical outcome after aortic valve replacement with the Biocor stentless aortic bioprosthesis. Patients and methods. Between October 1990 and November 2000 we inserted the Biocor stentless aortic valve in 112 patients (male/female: 38:74) with a mean age of 78.5 years (median 79.3, range 60-88). The predominant diagnosis was aortic stenosis in 86% of the patients. Concomitant coronary artery bypass surgery was performed in 31% of the patients. Average prosthetic valve size was 23.3 +/- 1.6 mm. All patients were followed in a prospective study with a mean follow-up of 66 +/- 33 months. The follow-up was 100% complete with a closing interval from October I to December 31, 2001. The observed actuarial survival of patients was compared to expected survival for an age- and gender-matched comparison population as calculated from Swedish life tables by Statistics Sweden. Relative survival rates were calculated annually for the patient population. Results. Early mortality was 7% (8/112). Late mortality was 38% (43/112). Actuarial survival at 5 and 9 years was 74 +/- 5% and 38 +/- 7%, respectively. Observed survival among patients was not different from the expected survival for the comparison population and calculation of relative survival rates indicates a 'normalized' survival pattern for the patient population. At 5 and 9 years the actuarial freedom from valve-related death was 94 +/- 3% and 86 +/- 6%; from cardiac death, 82 +/- 4% and 57 +/- 8%; from valve reoperation, 96 +/- 2% and 87 6%; from structural valve degeneration, 96 +/- 2% and 87 +/- 6%; from thromboembolism, 89 +/- 4% and 71 +/- 9%; and from endocarditis, 96 +/- 2% and 90 +/- 5%. At 9 years the transvalvular mean pressure difference for all valves was 7.3 +/- 1.3 mmHg (range 6-10 mmHg) measured with Doppler echocardiography. Aortic regurgitation progressed slowly over time in a few patients and necessitated reoperation in two patients. Conclusion. The Biocor stentless bioprosthesis has an excellent hemodynamic function and confers a good long-term outcome. This patient population could be regarded as 'cured' from valve disease since the observed survival did not differ from the expected survival for an age- and gender-matched Swedish comparison population, a conclusion that is also supported by a constant relative survival after the first postoperative year. However, despite excellent long-term hemodynamics, patients with stentless bioprostheses need to be evaluated with echocardiography at regular intervals to discover the rare cases of progressive aortic regurgitation.

  • 20. Ehrenberg, J.
    et al.
    Intonti, M.
    Owall, A.
    Brodin, Lars-Åke
    Ivert, T.
    Lindblom, D.
    Retrograde crystalloid cardioplegia preserves left ventricular systolic function better than antegrade cardioplegia in patients with occluded coronary arteries2000In: Journal of Cardiothoracic and Vascular Anesthesia, ISSN 1053-0770, E-ISSN 1532-8422, Vol. 14, no 4, p. 383-387Article in journal (Refereed)
    Abstract [en]

    Objective: To investigate retrograde and antegrade crystalloid cardioplegia in terms of cardiac cooling and postoperative cardiac function. Design: Prospective, randomized, and blinded. Setting: University hospital. Participants: Twenty male patients with triple-vessel disease and proximal occlusion of the circumflex or the left anterior descending coronary artery. Interventions: Left ventricular ejection fraction at rest and during exercise was evaluated by nuclear ventriculography the day before and 3 months after surgery. After induction of anesthesia and hourly for the first 5 postoperative hours, hemodynamic. echocardiographic, and electrocardiographic data were acquired. Myocardial temperature was measured with needle thermistors in 3 myocardial regions. Measurements and Main Results: Demographic and temperature data were analyzed by t-test. Hemodynamic and echocardiographic data were analyzed by analysis of variance. The groups were similar in baseline characteristics. Retrograde cardioplegia cooled the region distal to an occlusion better than antegrade cardioplegia (9.6 degrees C +/- 4.8 degrees C v 21.8 degrees C +/- 5.9 degrees C; p < 0.01). Hemodynamic, echocardiographic, and electrocardiographic data did not differ between the groups. Three months after surgery, the retrograde cardioplegia group showed a higher left ventricular ejection fraction at rest (58% +/- 10% v 47% +/- 10%; p < 0.02) and during exercise (58% +/- 13% v 47% +/- 10%; p < 0.05) compared with the antegrade cardioplegia group. Conclusions: Retrograde cardioplegia provides more homogenous myocardial cooling than antegrade cardioplegia in hearts with coronary artery occlusions. The use of retrograde cardioplegia seems to benefit long-term left ventricular function.

  • 21.
    Elmstedt, Nina
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, Kjerstin
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Westgren, Magnus
    Fetal cardiac muscle contractility decreases with gestational age: a color-coded tissue velocity imaging study2012In: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 10, p. 19-Article in journal (Refereed)
    Abstract [en]

    Background: Present data regarding how the fetal heart works and develops throughout gestation is limited. However, the possibility to analyze the myocardial velocity profile provides new possibilities to gain further knowledge in this area. Thus, the objective of this study was to evaluate human fetal myocardial characteristics and deformation properties using color-coded tissue velocity imaging (TVI). Methods: TVI recordings from 55 healthy fetuses, at 18 to 42 weeks of gestation, were acquired at a frame rate of 201-273 frames/s for offline analysis using software enabling retrieval of the myocardial velocity curve and 2D anatomical information. The measurements were taken from an apical four-chamber view, and the acquired data was correlated using regression analysis. Results: Left ventricular length and width increased uniformly with gestational age. Atrioventricular plane displacement and the E'/A' ratio also increased with gestational age, while a longitudinal shortening was demonstrated. Conclusions: Fetal cardiac muscle contractility decreases with gestational age. As numerous fetal-and pregnancy-associated conditions directly influence the pumping function of the fetal heart, we believe that this new insight into the physiology of the human fetal cardiovascular system could contribute to make diagnosis and risk assessment easier and more accurate.

  • 22.
    Elmstedt, Nina
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, Kjerstin
    CFM, Karolinska Universitetssjukhuset.
    Westgren, Magnus
    CFM, Karolinska Universitetssjukhuset.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Reference values for fetal tissue velocity imaging and a new approach to evaluate fetal myocardial function2013In: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 11, no 1, p. 29-Article in journal (Refereed)
    Abstract [en]

    Objectives: Myocardial function can be evaluated using color-coded tissue velocity imaging (TVI) to analyze the longitudinal myocardial velocity profile, and by expressing the motion of the atrioventricular plane during a cardiac cycle as coordinated events in the cardiac state diagram (CSD). The objective of this study was to establish gestational age specific reference values for fetal TVI measurements and to introduce the CSD as a potential aid in fetal myocardial evaluation. Methods: TVI recordings from 125 healthy fetuses, at 18 to 42 weeks of gestation, were performed with the transducer perpendicular to the apex to provide a four-chamber view. The myocardial velocity data was extracted from the basal segment of septum as well as the left and right ventricular free wall for subsequent offline analysis. Results: During a cardiac cycle the longitudinal peak velocities of septum increased with gestational age, as did the peak velocities of the left and right ventricular free wall, except for the peak velocity of post ejection. The duration of rapid filling and atrial contraction increased during pregnancy while the duration of post ejection decreased. The duration of pre ejection and ventricular ejection did not change significantly with gestational age. Conclusion: Evaluating fetal systolic and diastolic performance using TVI together with CSD could contribute to increase the knowledge and understanding of fetal myocardial function and dysfunction. The pre and post ejection phases are the variables most likely to indicate fetuses with abnormal myocardial function.

  • 23.
    Elmstedt, Nina
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, K.
    Westgren, M.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Fetal heart contractile function and gestational age2012In: Cardiovascular Research, ISSN 0008-6363, E-ISSN 1755-3245, Vol. 93, p. S108-S108Article in journal (Other academic)
  • 24.
    Elmstedt, Nina
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, K.
    Westgren, M.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Temporal frequency requirements for tissue velocity imaging of the fetal heart2011In: Ultrasound in Obstetrics and Gynecology, ISSN 0960-7692, E-ISSN 1469-0705, Vol. 38, no 4, p. 413-417Article in journal (Refereed)
    Abstract [en]

    Objectives The high velocity and short duration of myocardial motion requires a high sampling rate to obtain adequate temporal resolution; this issue becomes even more important when taking into consideration the high fetal heart rate. In this study we have established optimal sampling requirements for assessing the duration of various cardiac cycle events and myocardial velocities of the fetal heart using color-coded tissue velocity imaging (TVI). Methods Recordings from 30 fetuses were acquired at an initial frame rate of 180-273 frames/s. All TVI recordings were performed from an apical four-chamber view and stored as cineloops of five to 10 consecutive cardiac cycles for subsequent offline analysis using software enabling a reduction in frame rate. Different components of the myocardial velocity curve, obtained from the basal part of the ventricular septum, were measured at the initial frame rate and compared with their equivalents at gradually decreased frame rates. Results As acquisition frame rate was reduced, there was a marked increase in deviation from the initial values, resulting in an underestimation of all systolic and diastolic velocities. For the measured durations, there was a clear tendency to underestimate isovolumetric contraction and relaxation, and a clear tendency to overestimate ventricular ejection and diastolic E-wave and A-wave. An acceptable <= 5% deviation from the value obtained at the highest frame rate corresponded to measurements obtained at above 150-200 frames/s. Conclusions A high sampling rate of at least 200 frames/s is necessary for adequate reconstruction of TVI data for the fetal heart. Frame rates that are too low result in considerable loss of temporal and velocity information.

  • 25.
    Elmstedt, Nina
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    KTH, School of Technology and Health (STH).
    Ferm-Widlund, Kjerstin
    CFM, Karolinska Universitetssjukhuset.
    Westgren, Magnus
    CFM, Karolinska Universitetssjukhuset.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Reproducibility and variability in the assessment of color-coded tissue velocity imaging of the fetal myocardium2013In: Journal of biomedical graphics and computing, ISSN 1925-4008, Vol. 3, no 2Article in journal (Refereed)
    Abstract [en]

    Objective: The introduction of color-coded tissue velocity imaging (TVI) in fetal medicine is quite recent, and as this method is presently evaluated and developed in regard to diagnostic precision it is of outmost importance to evaluate the reproducibility for adequate clinical use. In this study, reproducibility and intra- and inter-observer variability was assessed for offline analysis as well as echocardiography investigations. Also, we evaluated the importance of exact placement of the region of interest (ROI).

    Methods: TVI recordings from 21 fetuses, at a gestational age of 27 to 41 weeks, were acquired at 208-239 frames/s for subsequent offline analysis. All recordings were performed with the transducer positioned to provide an apical four-chamber view and the myocardial velocity data was obtained from basal inferoseptum. The data set was analyzed according to Bland-Altman and reproducibility was expressed as the standard error of a single determination, estimated from duplicate determinations in percentage of the total.

    Results: The variation of reproducibility for the echocardiography investigation ranged from 2.0% to 9.8%. The duration of left ventricular ejection, and the peak velocities of early diastolic filling and atrial contraction being the most robust events measured. The variation of inter-observer variability for the echocardiography investigation ranged from 1.5% to 8.4%, and the variation of intra- and inter-observer variability for the offline analysis ranged from 1.2% to 10.4%. Least robust were the events of shortest duration, including isovolumetric contraction and relaxation.

    Conclusion: We believe that TVI measurements of the fetal myocardium could be performed in the clinical routine with acceptable reproducibility.

  • 26. Ericsson, Anders B.
    et al.
    Kronander, Håkan
    Söderqvist, Emil
    Vaage, Jarle
    Brodin, Lars-Åke
    Correlation between a Mid-ventricular Volume Segment and Global Left Ventricular Volume Measured by the Conductance Catheter2001In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 35, no 2, p. 129-135Article in journal (Refereed)
    Abstract [en]

    Objectives-To investigate whether acute volume changes in single volume segments of the left ventricle can be correlated with global volume changes. If so, changes in global volume might be predicted from changes in segmental volumes.

    Design-Volume changes were recorded in six pigs in five intraventricular segments, from apex to heart base, using the conductance catheter (at baseline, after 60 min of apical ischaemia, during preload reduction and afterload increase). A computer algorithm was created to calculate the instantaneous absolute difference between the curve shape of global and normalized segmental volume as a percentage of global stroke volume.

    Results-For a mid-cardiac volume segment constituting 34 (14-39)% [median (range)] of global stroke volume, the mean difference over a cardiac cycle was 4 (1-8)% at baseline. Apical ischaemia resulted in apical dyskinesia, but did not influence the mid-cardiac segment.

    Conclusions-The volume curve from a segment at mid-cardiac level seems to be a good estimator of the global volume curve, thus giving a foundation for estimation of global volume changes from such a segment.

  • 27.
    Erlandsson, Björn-Erik
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Medicinsk säkerhet2016In: Anestesi / [ed] Sten GE Lindahl, Ola Winsö, Jonas Åkeson, Stockholm: Liber AB , 2016, 3, p. 168-173Chapter in book (Other academic)
  • 28. Gaballa, Mohsen
    et al.
    Taher, Taha
    Brodin, Lars-Åke
    Karolinska Hospital, Stockholm, Sweden .
    van der Linden, Jan
    O'Reilly, Ken
    Hui, W
    Brass, Neil
    Cheung, P K
    Grip, Lars
    Images in cardiovascular medicine. Myocardial infarction as a rare consequence of a snakebite: diagnosis with novel echocardiographic tissue Doppler techniques2005In: Circulation, ISSN 0009-7322, E-ISSN 1524-4539, Vol. 112, no 11, p. e140-142Article in journal (Other academic)
  • 29. Gardeback, M.
    et al.
    Settergren, G.
    Brodin, Lars-Åke
    Jorfeldt, L.
    Galuska, D.
    Ekberg, K.
    Wahren, J.
    Splanchnic blood flow and oxygen uptake during cardiopulmonary bypass2002In: Journal of Cardiothoracic and Vascular Anesthesia, ISSN 1053-0770, E-ISSN 1532-8422, Vol. 16, no 3, p. 308-315Article in journal (Refereed)
    Abstract [en]

    Objective: To measure splanchnic blood flow (SBF) with 2 indicator dilution techniques during and after cardiopulmonary bypass (CPB), to compare the results with transesophageal echocardiography Doppler-measured right hepatic vein (RHV) flow, and to study gastric tonometry data in the same patients. Design: Single-arm prospective study. Setting: University hospital operating room and intensive care unit. Participants: Ten adult patients undergoing cardiac surgery. Interventions: SBF was measured using constant rate in fusion of indocyanine green dye and low-dose ethanol from induction of anesthesia until end of hypothermic CPB. The infusion of ethanol was continued, and SBF was measured postoperatively at 2, 3, and 4 hours after CPB. Simultaneously, RHV flow, splanchnic oxygen delivery and uptake, and gastric mucosal pH were calculated. Measurements and Main Results: SBF, RHV flow, and gastric mucosal pH remained unchanged during the study period. SBF measured with indocyanine green was 765 +/- 88 (SEM) mL/min after induction of anesthesia. SBF before CPB measured with ethanol was 985 +/- 218 mL/min. There was no significant difference between the methods. RHV flow was 450 +/- 87 mL/min after induction of anesthesia. There was no correlation between individual values of RHV flow and SBF. Splanchnic oxygen uptake was 52 +/- 7.8 mL/min after induction of anesthesia and decreased to 28 +/- 2.6 mL/min during CPB. Gastric mucosal pH was 7.32 +/- 0.02 after induction of anesthesia and showed no correlation to SBF or to splanchnic oxygen uptake. Conclusion: SBT did-not decrease during CPB. SBF could be measured with ethanol with reasonable accuracy. Transesophageal echocardiography assessment of RHV flow was not suitable to quantify SBF in the individual patient, but could be used to follow relative changes.

  • 30.
    Govind, Satish C.
    et al.
    BMJ Heart Center, Bangalore, India.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nowak, J.
    Karolinska Institute, Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Arvind, S. R.
    BMJ Heart Center, Bangalore, India.
    Ramesh, S. S.
    BMJ Heart Center, Bangalore, India.
    Netyö, A.
    Karolinska Institute, Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Prasad, K.Y.M.
    BMJ Heart Center, Bangalore, India.
    Saha, S.
    Karolinska Institute, Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Microalbuminuria and Left Ventricular Functions in Type 2 Diabetes: A Quantitative Assessment by Stress Echocardiography in the Myocardial Doppler in Diabetes (MYDID) Study III2007In: International Journal of Cardiology, ISSN 0167-5273, E-ISSN 1874-1754, Vol. 41, no 6, p. 363-369Article in journal (Refereed)
    Abstract [en]

    Background. Left ventricular (LV) function might be altered in type 2 diabetes (DM) and microalbuminuria (MA) may accentuate the abnormalities. We sought to investigate whether additional LV dysfunction could be unmasked using tissue Doppler (TVE)-enhanced dobutamine stress echocardiography (TVE-DSE) in patients with DM+MA. Methods. Twenty seven DM subjects with MA, (DM+MA), 31 DM subjects without MA (DM-MA), and 13 Controls were evaluated using TVE-DSE. LV basal peak systolic (PSV), early (E') and late (A') diastolic velocities (cm/sec) at rest and peak stress were post-processed. LV filling pressure was assessed using E/E'ratio. Results. PSV and E'velocity at peak stress in the respective three groups were 13.7±1.0, 10.1±1.1, 10.0±1.2 for PSV; and 10.0±1.6, 5.0±1.4, 4.8±1.4 for E' (p < 0.001 for controls vs. both groups). E/E' at rest was 7.9±0.7 in the controls, 10.8±2.4 in DM-MA, and 11.0±2.2 in DM+MA (p < 0.01 Controls vs. both the DM groups). Conclusions. Patients with DM+MA do not have additional LV regional systolic and diastolic dysfunctions compared with DM-MA, as revealed by TVE-DSE, when controlled for glycemia levels, lipids, and treatment strategies.

  • 31.
    Govind, Satish C.
    et al.
    BMJ Heart Center, Bangalore, India.
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Nowak, J.
    Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Quintana, M.
    Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Raumina, S.
    Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Ramesh, S.S.
    BMJ Heart Center, Bangalore, India.
    Keshava, R.
    BMJ Heart Center, Bangalore, India.
    Saha, S.
    Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Isolated Type 2 Diabetes mellitus Causes Myocardial Dysfunction That Becomes Worse in the Presence of Cardiovascular Diseases: Results of the Myocardial Doppler in Diabetes (MYDID): Study 12005In: Cardiology, ISSN 0008-6312, E-ISSN 1421-9751, Vol. 103, no 4, p. 189-195Article in journal (Refereed)
    Abstract [en]

    Aims: Patients with type 2 diabetes mellitus (DM) often suffer disproportionately and have a worse outcome when burdened with cardiovascular complications compared with those without DM. A specific heart muscle disease reportedly caused by DM per se may explain this. We sought to investigate whether an echo Doppler diagnosis of such a myocardial disease is clinically relevant in DM with or without coexistent coronary artery disease (CAD) and/or hypertension ( HTN). Subjects and Methods: Two hundred subjects (127 males, 73 females, 56 +/- 10 years) including controls (n=23), patients with HTN (n=20), CAD (n=35), uncomplicated DM (n=59), DM+HTN (n=27), DM+ CAD (n=16) and DM+CAD+HTN (n=20) underwent tissue Doppler-enhanced dobutamine stress echocardiography. Myocardial function was assessed by measuring left ventricular myocardial peak systolic velocity (PSV) and early diastolic velocity at rest and during peak stress, besides measurements of standard Doppler variables. Results: Average left ventricular PSV at rest was significantly lower in CAD (4.7 +/- 1.5) compared with controls (5.7 center dot +/- 1.2) and in DM+CAD+HTN (4.6 +/- 1.4) compared with DM (5.6 +/- 1.3; all p < 0.05). During peak stress, lower PSV persisted in CAD (9.5 +/- 3.1) and DM+CAD+HTN (8.1 +/- 2.7), while appearing de novo in DM (11.3 +/- 2.6) and HTN (11.0 +/- 2.3) unlike in the controls (12.5 +/- 2.5; all p < 0.001). When pooled together, DM subjects with CAD and/or HTN or both had significantly lower PSV (9.1 +/- 2.7) than those without (10.0 +/- 2.8; p < 0.001). Early diastolic velocity response was equally lower in both groups compared with the controls. Conclusion: The results suggest that dobutamine stress unmasks myocardial functional disturbances caused by uncomplicated DM. The discrete disturbances become quantitatively more pronounced in the presence of coexistent cardiovascular diseases.

  • 32.
    Govind, Satish C.
    et al.
    BMJ Heart Center, Department of Non-invasive Cardiology, Bangalore, India.
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska University Hospital at Huddinge.
    Nowak, J.
    BMJ Heart Center, Department of Non-invasive Cardiology, Bangalore, India.
    Ramesh, S. S.
    BMJ Heart Center, Department of Non-invasive Cardiology, Bangalore, India.
    Saha, S. K.
    Department of Clinical Physiology, Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Acute administration of a single dose of valsartan improves left ventricular functions: a pilot study to assess the role of tissue velocity echocardiography in patients with systemic arterial hypertension in the TVE-valsartan study I2006In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 26, no 6, p. 351-356Article in journal (Refereed)
    Abstract [en]

    Background The advent of colour-coded tissue velocity echocardiography (TVE) has now made it possible to quantify left ventricular (LV) functions in patients with systemic arterial hypertension (HTN).

    Hypothesis In this project, we have studied the cardiac effects of a single dose of orally administered valsartan in patients with known HTN.

    Methods Fifty-five patients with HTN with a mean age of 56 +/- 10 years were given an early morning dose of 80 mg valsartan withholding regular antihypertensive medications on the day of investigation. TVE images, acquired on VIVID systems were digitized for postprocessing of longitudinal and radial peak systolic velocities, strain rate, and systolic and diastolic time intervals before (pre) and 5 h after (post) administration of the drug.

    Results Blood pressure (mmHg) pre and post, respectively, were 147 +/- 15 versus 137 +/- 14 systolic and 90 +/- 7 versus 86 +/- 7 diastolic (all P < 0.01). LV longitudinal systolic velocities (cm s(-1)) were significantly higher post in LV septum (5.7 +/- 1.1 versus 6.4 +/- 1.6; P < 0.001) with similar results obtained in other LV walls. Radial strain rate (1 s(-1)) was significantly higher post compared with pre valsartan (2.1 +/- 0.6 versus 2.3 +/- 0.9; P < 0.01). Regional diastolic filling and ejection times (ms) were significantly shorter post (390 +/- 122 versus 370 +/- 120 and 275 +/- 32 versus 163 +/- 36 respectively; all P < 0.05).

    Conclusions Within 5 h after oral administration of valsartan, improvement in regional myocardial systolic functions could be registered. Although the changes could well be secondary to afterload reduction, additional effects of the drug, evidenced by improved strain rate that is relatively load-independent, may have contributed in this improvement.

  • 33. Govind, Satish C.
    et al.
    Gopal, Aasha S.
    Netyo, Anita
    Nowak, Jacek
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Patrianakos, Alexandros
    Ramesh, S. S.
    Saha, Samir
    Quantification of low-dose dobutamine stress using speckle tracking echocardiography in coronary artery disease2009In: European Journal of Echocardiography, ISSN 1525-2167, E-ISSN 1532-2114, Vol. 10, no 5, p. 607-612Article in journal (Refereed)
    Abstract [en]

    Aims We sought to evaluate the utility of speckle tracking echocardiography (STE) for detecting left ventricular (LV) mechanical abnormalities during low-dose (20 mu g) dobutamine stress (DSE). Methods and results Twenty-nine patients (56 +/- 12 years) with a history of recent acute coronary events (ACE) underwent STE-DSE. Left ventricular images, sampled at frame rates 70-100 Hz, were analysed off-line (Echopac BT 6.0.0). Velocity, strain, and rotational imaging were performed. Twenty patients had LV ejection fraction (EF) >40% (Group 1) whereas nine patients had LVEF <40% (Group 2). Average heart and frame rates were identical during DSE in the two groups (P = ns). Global circumferential strain (%) was significantly lower in Group 2 compared with Group 1 (10.65 +/- 5.30 vs. 16.82 +/- 6.61; P < 0.05) at rest and during peak stress (14.72 +/- 6.51 vs. 21.13 +/- 7.2; P < 0.05). The global peak rotation rate (degree/s) was, however, higher at rest in Group 2 (70 +/- 97 vs. 19 +/- 67; P < 0.05) and 20 mu g stress. Peak systolic velocity increased in three of the four LV walls at 20 mu g ( in Groups 1 and 2). A global rotational rate increased significantly at 20 mu g during systole in both the groups, but was unchanged in Group 2 during diastole. Conclusions Speckle tracking echocardiography dobutamine stress appears to provide comprehensive information on LV mechanical status in the aftermath of ACE. The modality may help risk stratify such patients.

  • 34. Govind, Satish C
    et al.
    Kiotsekoglou, Anatoli
    Gadiyaram, Varuna K
    Gopal, Aasha S
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ramesh, Saligrama S
    Saha, Samir K
    Role of N-terminal pro-brain natriuretic peptide in ST-segment elevation myocardial infarction: experience from a tertiary centre in India.2011In: Critical Pathways in Cardiology, ISSN 1535-282X, E-ISSN 1535-2811, Vol. 10, no 4, p. 180-184Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Role of biomarkers in ST-segment elevation myocardial infarction (STEMI) is paramount, as they aid in diagnosis and gauge prognosis of the disease. In this project, we sought to study the short-term outcome and clinical associates of N-terminal pro-brain natriuretic peptide (NT-proBNP) in the setting of STEMI at a tertiary center in India.

    METHODS: In all, 173 STEMI patients (mean age: 57 ± 12 years, 38 women) had their NT-proBNP assayed in addition to troponins and high-sensitive C-reactive protein. Subjects were divided according to NT-proBNP levels into 2 groups: group 1 (NT-proBNP ≤100 pg/mL) and group 2 (NT-proBNP >100 pg/mL).

    RESULTS: NT-proBNP values (pg/mL) were elevated in group 2 (group 1: 61.7 ± 6.2; group 2: 1006.5 ± 990.6, P < 0.0001). Significantly greater number of females had elevated NT-proBNP (P < 0.05) that could be predicted by the duration of chest pain related to STEMI (area under the curve: 0.72), and age at presentation (area under the curve: 0.66). Multiple regression analysis showed a strong inverse association between NT-proBNP and left ventricular ejection fraction and a strong positive association between the peptide and high-sensitive C-reactive protein. A significant positive association was also noted between NT-proBNP and troponin I (all P < 0.05, Global R = 0.47). Diabetes mellitus and/or hypertension, and infarction localization showed no effect on NT-proBNP levels along with death, primary coronary intervention-related bleeding, and arrhythmias, (χ, P = ns).

    CONCLUSIONS: The data suggest that women are more likely to have increased NT-proBNP while presenting with STEMI. Duration of chest pain and age at presentation are the best predictors of elevated NT-proBNP, though without much bearing on short-term morbidity and mortality.

  • 35.
    Govind, Satish C.
    et al.
    Bhagwan Mahavir Jain Heart Center, Bangalore, India.
    Roumina, S.
    Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nowak, J.
    Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Ramesh, S. S.
    Bhagwan Mahavir Jain Heart Center, Bangalore, India.
    Saha, S. K.
    Karolinska University Hospital at Huddinge, Stockholm, Sweden.
    Differing myocardial response to a single session of hemodialysis in end-stage renal disease with and without type 2 diabetes mellitus and coronary artery disease2006In: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 4, no 9Article in journal (Refereed)
    Abstract [en]

    Background: Though hemodialysis (HD) acutely improves cardiac function, the impact of background diseases like coronary artery disease (CAD) and Type 2 diabetes (DM) in the setting of end-stage renal disease (ESRD) is not known. Tissue velocity echocardiography (TVE) offers a fast choice to follow changes in myocardial function after HD in ESRD with concomitant DM and/or CAD. Methods: 46 subjects (17 with ESRD, Group 1; 15 with DM, Group 2; 14 with DM+CAD, Group 3) underwent standard and TVE prior to and shortly after HD. Besides standard Doppler variables, regional myocardial systolic and diastolic velocities, as well as systolic strain rate were post processed. Results: Compared with pre-HD, post-HD body weight (kg) significantly decreased in all the three groups (51 ± 9 vs. 48 ± 8, 62 ± 10 vs.59 ± 10, and 61 ± 9 vs. 58 ± 9 respectively; all p < 0.01). Left ventricular end diastolic dimensions (mm) also decreased post- HD (46 ± 5 vs. 42 ± 7, 53 ± 7 vs. 50 ± 7, 51 ± 7 vs. 47 ± 8 respectively; all p < 0.01). Regional longitudinal peak systolic velocity in septum (cm/s) significantly increased post-HD in Group 1(5.7 ± 1.6 vs. 7.2 ± 2.3; p < 0.001) while remained unchanged in the other two groups. Similar trends were noted in other left ventricular walls. When the myocardial velocities (cm/s) were computed globally, the improvement was seen only in Group 1 (6.3 ± 1.5 vs. 7.9 ± 2.0; p < 0.001). Global early regional diastolic velocity (cm/s) improved in Group 1, remained unchanged in Group 2, while significantly decreased in Group 3(-5.9 ± 1.3 vs. -4.1 ± 1.8; p < 0.01). Global systolic strain rate (1/sec) increased in the first 2 Groups but remained unchanged (-0.87 ± 0.4 vs. -0.94 ± 0.3; p = ns) in Group 3. Conclusion: A single HD session improves LV function only in ESRD without coexistent DM and/or CAD. The present data suggest that not only dialysis-dependent changes in loading conditions but also co-existent background diseases determine the myocardial response to HD.

  • 36.
    Govind, Satish C.
    et al.
    Department of Clinical Physiology, Karolinska Institute, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    Saha, S.
    Department of Clinical Physiology, Karolinska Institute, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska Institute, Karolinska University Hospital, Huddinge.
    Ramesh, S. S.
    BMJ Heart Center, Bangalore, India.
    Arvind, S. R.
    BMJ Heart Center, Bangalore, India.
    Quintana, M.
    Department of Clinical Physiology, Karolinska Institute, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    Impaired Myocardial Functional Reserve in Hypertension and Diabetes Mellitus Without Coronary Artery Disease: Searching for the Possible Link With Congestive Heart Failure in the Myocardial Doppler in Diabetes (MYDID) Study II2006In: American Journal of Hypertension, ISSN 0895-7061, E-ISSN 1941-7225, Vol. 19, no 8, p. 851-857Article in journal (Refereed)
    Abstract [en]

    Background: Although the impact of type 2 diabetes mellitus (DM) and hypertension (HTN) on myocardial function has recently been studied using tissue Doppler echocardiography (TDE), the independent role of both conditions, and the influence of other risk factors on myocardial function has not been completely defined, particularly in absence of coronary artery disease (CAD). The aim of this study was to assess the myocardial functional reserve in patients with DM or HTN with apparently normal left ventricular (LV) systolic function.

    Methods: Standard and dobutamine stress echocardiography using TDE was performed in 128 subjects: 59 had DM, 20 had HTN, 27 had both DM and HTN (HTN + DM), and 22 subjects were controls (C). Subjects with known CAD and depressed LV function were excluded. In addition, standard two-dimensional and Doppler measurements, LV regional peak systolic (PSV), early (E') and late (A') diastolic velocities, strain (S%) and strain rate (SR), were assessed at rest and peak stress.

    Results: The LV mass did not differ, although relative wall thickness was significantly higher in subjects with HTN + DM and HTN. The PSV did not differ at rest but was lowest in subjects with HTN + DM at peak stress. The E' wave velocity was significantly lower in subjects with HTN + DM both at rest and during peak stress, as were S% and SR.

    Conclusions: The addition of DM to HTN has a negative effect on LV systolic and diastolic functions. A depressed myocardial functional reserve might be postulated as one of the pathophysiologic mechanisms for the excessive occurrence of congestive heart failure in patients with DM or HTN.

  • 37. Govindan, Malini
    et al.
    Kiotsekoglou, Anatoli
    Batchvarov, Velislav
    Saha, Samir K.
    Dougal, Kate
    Teoh, Evaun
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Camm, John
    LEFT ATRIAL EXPANSION INDEX IN PATIENTS WITH ATRIAL FIBRILLATION IS A PREDICTOR OF SINUS RHYTHM MAINTENANCE AFTER CARDIOVERSION2010In: Journal of the American College of Cardiology, ISSN 0735-1097, E-ISSN 1558-3597, Vol. 55, no 10Article in journal (Other academic)
  • 38.
    Grishenkov, Dmitry
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brismar, Torkel B.
    CLINTEC, Department of Radiology, Karolinska University Hospital.
    Paradossi, Gaio
    Dipartimento di Chimica, Università di Roma Tor Vergata.
    On comparison between polymer- and phospholipid-shelled microbubbles for contrast-enhanced ultrasound measurements of capillary microcirculation.2011In: Proceedings of the 34th Scandinavian Symposium on Physical Acoustics / [ed] Rolf J. Korneliussen, 2011Conference paper (Refereed)
    Abstract [en]

    The focus of contrast-enhanced ultrasound research has developed beyond visualizing the blood circulation to new areas such as perfusion and molecular imaging, drug and gene therapy. This work compares the application of polymer- and phospholipid-shelled ultrasound contrast agents (UCAs) employed for characterization of the capillary microcirculation. To quantify microcirculation destruction/replenishment technique with varied time intervals between destructive and monitoring pulses is used. The dependence of the peak-to-peak amplitude of backscattered wave versus pulse interval is fitted with an exponential function of the time y=A(1-exp(-βt)) , where A represents capillary volume and the time constant β represents velocity of the flow. Working under assumption that backscattered signal is linearly proportional to the microbubble concentration, for both types of the UCAs it is observed that capillary volume, A, is in linearly relationship with the concentration, and the flow velocity, β, remain unchanged. Using 500 µm diameter microtube as a vessel phantom a delay of about 0.25 s in evaluation of the perfusion characteristics is found for the phospholipid-shelled UCA, while polymer-shelled UCA provide response immediately. In conclusion, these results suggest that the novel polymer-shelled microbubbles have a potential to be used for perfusion evaluation.

  • 39.
    Grishenkov, Dmitry
    et al.
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, Marcus Wallenberg Laboratory MWL.
    Kari, Leif
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering, MWL Structural and vibroacoustics.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brismar, Torkel B.
    CLINTEC, Department of Radiology, Karolinska Institutet.
    Paradossi, Gaio
    Dipartimento di Chimica, THE UNIVERSITY OF ROME.
    In vitro contrast-enhanced ultrasound measurements of capillary microcirculation: Comparison between polymer- and phospholipid-shelled microbubbles2011In: Ultrasonics, ISSN 0041-624X, E-ISSN 1874-9968, Vol. 51, no 1, p. 40-48Article in journal (Refereed)
    Abstract [en]

    The focus of contrast-enhanced ultrasound research has developed beyond visualizing the blood pool and its flow to new areas such as perfusion imaging, drug and gene therapy, and targeted imaging. In this work comparison between the application of polymer- and phospholipid-shelled ultrasound contrast agents (UCAs) for characterization of the capillary microcirculation is reported. All experiments are carried out using a microtube as a vessel phantom. The first set of experiments evaluates the optimal concentration level where backscattered signal from microbubbles depends on concentration linearly. For the polymer-shelled UCAs the optimal concentration level is reached at a value of about 2 x 10(4) MB/ml, whereas for the phospholipid-shelled UCAs the optimal level is found at about 1 x 10(5) MB/ml.

    Despite the fact that the polymer shell occupies 30% of the radius of microbubble, compared to 0.2% of the phospholipid-shelled bubble, approximately 5-fold lower concentration of the polymer UCA is needed for investigation compared to phospholipid-shelled analogues. In the second set of experiments, destruction/replenishment method with varied time intervals ranging from 2 ms to 3 s between destructive and monitoring pulses is employed. The dependence of the peak-to-peak amplitude of backscattered wave versus pulse interval is fitted with an exponential function of the time gamma = A( 1 - exp(-beta t)) where A represents capillary volume and the time constant beta represents velocity of the flow. Taking into account that backscattered signal is linearly proportional to the microbubble concentration, for both types of the UCAs it is observed that capillary volume is linearly proportional to the concentration of the microbubbles, but the estimation of the flow velocity is not affected by the change of the concentration. Using the single capillary model, for the phospholipid-shelled UCA a delay of about 0.2-0.3 s in evaluation of the perfusion characteristics is found while polymer-shelled UCA provide response immediately. The latter at the concentration lower than 3.6 x 10(5) MB/ml have no statistically significant delay (p < 0.01), do not cause any attenuation of the backscattered signal or saturation of the receiving part of the system. In conclusion, these results suggest that the novel polymer-shelled microbubbles have a potential to be used for perfusion evaluation.

  • 40. Gunnes, S.
    et al.
    Storaa, C.
    Lind, Britta
    Department of Clinical Physiology, Karolinska Univ. Hospital Huddinge, Sweden.
    Nowak, J.
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska Univ. Hospital Huddinge, Sweden.
    Analysis of the effect of temporal filtering in myocardial tissue velocity imaging2004In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 17, no 11, p. 1138-1145Article in journal (Refereed)
    Abstract [en]

    Signal filtering to reduce random noise may compromise the reliability of tissue velocity measurements. This study evaluates the influence of temporal filters on time and velocity variables derived from myocardial tissue velocity images acquired in 15 healthy individuals at a high frame rate (142-184 Hz). Different time and velocity variables from the basal septum were analyzed offline before and after temporal filtering from 20 to 60 milliseconds in 10-millisecond steps using software enabling retrieval of myocardial Doppler velocity and 2-dimensional information from different cardiac locations during the same cardiac cycle. Filtering affected the results by increasing variability of time and by underestimation of velocity variables, the rapid isovolumic events being particularly filter sensitive. In addition, at a certain range of sampling rate, ambiguity of filtering effect was observed. This ought to be considered if an optimal, high-fidelity tissue Doppler velocity signal is to be obtained.

  • 41. Hagerman, I.
    et al.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering. Karolinska Universitetssjukhuset Huddinge, Sweden.
    Dahlström, U. L. F.
    Ekman, I.
    Willenheimer, R.
    Boman, K.
    Diastolisk hjärtsvikt - Symtom och etiologi2007In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 104, no 34, p. 2345-2347Article, review/survey (Refereed)
  • 42. Hanseus, K. C.
    et al.
    Bjorkhem, G. E.
    Brodin, Lars-Åke
    Pesonen, E.
    Analysis of atrioventricular plane movements by Doppler tissue imaging and M-mode in children with atrial septal defects before and after surgical and device closure2002In: Pediatric Cardiology, ISSN 0172-0643, E-ISSN 1432-1971, Vol. 23, no 2, p. 152-159Article in journal (Refereed)
    Abstract [en]

    Our objective was to compare the effects of surgical and device closure of atrial septal defects (ASDs) on atrioventricular plane function. In healthy individuals, both short- and long-axis motion contribute to ventricular pump function. Short-axis function (i.e., the amplitude and velocity of atrioventricular plane movements) may be evaluated by M-mode and Doppler tissue imaging. The study group consisted of 19 children with ASD of the secundum type before and after surgical (n = 12) or device (n = 7) closure and 10 healthy controls. Surgical and device closures were uncomplicated and all defects were completely closed. Registrations of atrioventricular plane systolic and diastolic amplitude and velocity were made from the tricuspid and the mitral annulus and from the septum in the apical four-chamber view. Comparisons were made between examinations before and after closure, between the two subgroups of patients treated by surgical and device closure, respectively, and between the patient group and the control groups. Before ASD closure, all measurements were normal or near normal. After surgery, systolic amplitudes and velocities of the tricuspid annulus and in the septum decreased significantly, whereas no changes were seen in the device group. Less marked changes were seen in diastolic measurements. However, in the surgical group significant decrease to subnormal values were found in the tricuspid annulus and in the septum, which may indicate a decreased diastolic function postoperatively. Mitral valve annulus amplitude and velocity were not affected by the treatment. Atrioventricular function is normal in children with right ventricular volume overload. The decrease to subnormal values after open-heart surgery is not seen after device closure of the ASD, indicating that surgery affects right ventricular function.

  • 43. Hao, Xiaojin
    et al.
    Mansson-Broberg, Agneta
    Grinnemo, Karl-Henrik
    Siddiqui, Anwar J.
    Dellgren, Goran
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska University Hospital.
    Sylven, Christer
    Myocardial angiogenesis after plasmid or adenoviral VEGF-A(165) gene transfer in rat myocardial infarction model2007In: Cardiovascular Research, ISSN 0008-6363, E-ISSN 1755-3245, Vol. 73, no 3, p. 481-487Article in journal (Refereed)
    Abstract [en]

    Objective: To compare gene transfer of plasmid (P) and adenovirus (Ad) encoding human vascular endothelial growth factor-A(165) (hVEGF-A(165)) angiogenic efficacy and adverse effects as regards apoptosis and ectopic expression of the transgene in a rat myocardial infarction model. Methods: Myocardial infarction was provoked in Fisher rats. One week later, PhVEGF-A(165), PLacZ, AdhVEGF-A(165), or AdLacZ was transferred intramyocardially along the border of the myocardial infarction. hVEGF-A expression was detected with ELISA. Myocardial vessel density was analyzed 1 and 4 weeks after gene transfer. Apoptosis was detected by TUNEL staining. Cardiac function was assessed with Tissue Doppler Velocity Imaging. Results: Although AdhVEGF-A(165) had substantially higher myocardial hVEGF-A expression than PhVEGF-A(165), AdhVEGF-A(165) and PhVEGF-A(165) induced angiogenic effects to a similar extent with maintained increased arteriolar density after 4 weeks of gene transfer (p < 0.05). The two treatments also improved left ventricular function similarly. Adenoviral gene transfer induced a higher number of TUNEL positive cells than plasmid (p < 0.02). Ectopic expression of the transgene was present with both vectors but substantially higher after adenoviral gene transfer. Conclusions: AdhVEGF-A165 has no obvious angiogenic advantage over PhVEGF-A165 but more side effects at least in a rat myocardial infarction model. This indicates that PhVEGF-A(165) might be more applicable for therapeutic angiogenesis than AdhVEGF-A(165).

  • 44. Hao, Xiaojin
    et al.
    Silva, Eduardo A.
    Mansson-Broberg, Agneta
    Grinnemo, Karl-Henrik
    Siddiqui, Anwar J.
    Dellgren, Goran
    Wardell, Eva
    Brodin, Lars-Åke
    Karolinska Institute, Department of Clinical Physiology, Karolinska University Hospital.
    Mooney, David J.
    Sylven, Christer
    Angiogenic effects of sequential release of VEGF-A(165) and PDGF-BB with alginate hydrogels after myocardial infarction2007In: Cardiovascular Research, ISSN 0008-6363, E-ISSN 1755-3245, Vol. 75, no 1, p. 178-185Article in journal (Refereed)
    Abstract [en]

    Objective: This study investigates whether local sequential delivery of vascular endothelial growth factor-A(165) (VEGF-A(165)) followed by platelet-derived growth factor-BB (PDGF-BB) with alginate hydrogels could induce an angiogenic effect and functional improvement greater than single factors after myocardial infarction. Methods: Alginate hydrogels were prepared by combining high and low molecular weight alginate. Growth factor release rates were monitored over time in vitro with I-125-labelled VEGF-A(165) and PDGF-BB included in the gels. One week after myocardial infarction was induced in Fisher rats, gels with VEGF-A(165), PDGF-BB, or both were given intra-myocardially along the border of the myocardial infarction. Vessel density was analysed in hearts and cardiac function was determined by Tissue Doppler Echocardiography. In addition, the angiogenic effect of sequenced delivery was studied in vitro in aortic rings from C57B1/6 mice. Results: Alginate gets were capable of delivering VEGF-A(165) and PDGF-BB in a sustainable manner, and PDGF-BB was released more slowly than VEGF-A(165). Sequential growth factor administration led to a higher density of alpha-actin positive vessels than single factors, whereas no further increment was found in capillary density. Sequential protein delivery increased the systolic velocity-time integral and displayed a superior effect than single factors. In the aortic ring model, sequential delivery led to a higher angiogenic effect than single factor administration. Conclusions: The alginate hydrogel is an effective and promising injectable delivery system in a myocardial infarction model. Sequential growth factor delivery of VEGF-A(165) and PDGF-BB induces mature vessels and improves cardiac function more than each factor singly. This may indicate clinical utility.

  • 45. Hashemi, N.
    et al.
    Samad, B. A.
    Hedman, A.
    Brodin, Lars Åke
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Alam, M.
    Feasibility of Myocardial Performance Index for Evaluation of Left Ventricular Function during Dobutamine Stress Echocardiography before and after Coronary Artery Bypass Grafting2014In: Echocardiography, ISSN 0742-2822, E-ISSN 1540-8175, Vol. 31, no 8, p. 989-995Article in journal (Refereed)
    Abstract [en]

    Aims: Myocardial performance index (MPI) is a measure of combined systolic and diastolic myocardial function. In patients with coronary artery disease (CAD) an increase in MPI is consistent with myocardial dysfunction. The objectives of this study were to characterize the changes in MPI after coronary artery bypass graft (CABG) at rest and at peak dobutamine stress echocardiography (DSE). Methods and Results: Thirty-six patients diagnosed with CAD and accepted for CABG were studied by standard echocardiography and DSE 1 month prior and 3 month after CABG. The MPI was calculated using pulsed-wave tissue Doppler imaging (PW-TDI) of the left ventricular (LV) wall-motion velocity. At baseline, ejection fraction (EF; 42.7 ± 8%) and wall-motion score index (WMSI; 1.1 ± 0.2) were impaired at rest as well as at peak DSE (EF; 49.2 ± 9 and WMSI 1.4 ± 0.2). MPI was prolonged both at rest (0.61 ± 0.13) and at peak DSE (0.78 ± 0.16). After CABG, EF and WMSI did not improve at rest (43.7 ± 8% and 1.1 ± 0.2, respectively). On the other hand, MPI improved substantially both at rest (0.45 ± 0.08; P < 0.001) and at peak DSE (0.56 ± 0.1; P < 0.001). At peak DSE an improvement of EF (54.2 ± 9; P < 0.05) and WMSI (1.1 ± 0.16; P < 0.001) was seen as well. Conclusion: Myocardial performance index shows significant improvement after CABG in patients with CAD both at rest and peak DSE and appears to be a sensitive measure of myocardial function.

  • 46.
    Hashemi, Nashmil
    et al.
    Danderyd Hosp, Unit Cardiol, Dept Clin Sci, Karolinska Inst, Stockholm, Sweden.;Capio St Gorans Hosp, Dept Clin Physiol, S-11281 Stockholm, Sweden..
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Hedman, Anders
    Soder Sjukhuset, Sect Cardiol, Dept Clin Sci, Karolinska Inst, Stockholm, Sweden..
    Samad, Bassem A.
    Danderyd Hosp, Unit Cardiol, Dept Clin Sci, Karolinska Inst, Stockholm, Sweden..
    Alam, Mahbubul
    Danderyd Hosp, Unit Cardiol, Dept Clin Sci, Karolinska Inst, Stockholm, Sweden..
    Improved right ventricular index of myocardial performance in the assessment of right ventricular function after coronary artery bypass grafting2018In: Interactive Cardiovascular and Thoracic Surgery, ISSN 1569-9293, E-ISSN 1569-9285, Vol. 26, no 5, p. 798-804Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: Decreased right ventricular (RV) longitudinal function following coronary artery bypass grafting (CABG), as assessed by tricuspid annular systolic excursion (TAPSE) and RV peak systolic velocity (RVS') is a known condition. We aimed to explore the feasibility of the right ventricular index of myocardial performance (RIMP) in the assessment of RV function after CABG at rest and during peak dobutamine stress echocardiography (DSE). METHODS: Forty-two patients indicated for CABG were included in this study. Coronary angiography, DSE and exercise bicycle test were performed within 6 weeks before and 3 months after CABG. The RIMP, RVS' and TAPSE at the lateral tricuspid annulus were also assessed. The results were presented as mean +/- standard deviation. RESULTS: The RIMP improved after CABG both at rest (0.45 +/- 0.11 before vs 0.38 +/- 0.08 after CABG, P= 0.013) and during DSE (0.75 +/- 0.23 vs 0.49 +/- 0.14, P < 0.001). TAPSE declined significantly when comparing the values from before CABG to after CABG both at rest (23.9 +/- 4.46 vs 14.6 +/- 3.67, P < 0.001) and during DSE (20.9 +/- 4.16 vs 11.9 +/- 3.60, P < 0.001). RVS' also decreased after CABG both at rest (11.9 +/- 2.40 vs 8.5 +/- 1.93, P < 0.001) and during DSE (15.6 +/- 4.30 vs 10.5 +/- 3.21, P <0.001). On the other hand, exercise capacity improved after CABG compared with baseline (128.4 +/- 40.12 W vs 142.1 +/- 46.73 W, P = 0.014). CONCLUSIONS: RIMP improved after CABG both at rest and during DSE. The reduction in TAPSE and RVS' after CABG indicate reduced regional mechanical RV function along the long axis rather than reduced global RV function.

  • 47. Hayashi, S. Y.
    et al.
    Seeberger, A.
    Lind, B.
    Gunnes, S.
    Lindholm, B.
    Brodin, Lars-Åke
    Acute effects of low intravenous doses of furosemide on left ventricular function in end stage renal disease patients evaluated by color tissue Doppler velocity imaging2005In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 26, p. 107-107Article in journal (Other academic)
  • 48.
    Hayashi, Shirley Yumi
    et al.
    Division of Baxter Novum, Department of Clinical Science, Karolinska Univ. Hospital.
    Brodin, Lars-Åke
    Department of Clinical Physiology, Karolinska Institutet, Karolinska Univ. Hospital.
    Alvestrand, Anders
    Division of Baxter Novum, Department of Clinical Science, Karolinska Univ. Hospital.
    Lind, Britta
    Department of Clinical Physiology, Karolinska Institutet, Karolinska Univ. Hospital.
    Stenvinkel, Peter
    Division of Baxter Novum, Department of Clinical Science, Karolinska Univ. Hospital.
    Mazza do Nascimento, Marcelo
    Division of Baxter Novum, Department of Clinical Science, Karolinska Univ. Hospital.
    Qureshi, Abdul Rashid
    Division of Baxter Novum, Department of Clinical Science, Karolinska Univ. Hospital.
    Saha, Samir
    Department of Clinical Physiology, Karolinska Institutet, Karolinska Univ. Hospital.
    Lindholm, Bengt
    Division of Baxter Novum, Department of Clinical Science, Karolinska Univ. Hospital.
    Seeberger, Astrid
    Division of Baxter Novum, Department of Clinical Science, Karolinska Univ. Hospital.
    Improvement of cardiac function after haemodialysis: Quantitative evaluation by colour tissue velocity imaging2004In: Nephrology, Dialysis and Transplantation, ISSN 0931-0509, E-ISSN 1460-2385, Vol. 19, no 6, p. 1497-1506Article in journal (Refereed)
    Abstract [en]

    Background. Overhydration and accumulation of uraemic toxins may influence the myocardial function in haemodialysis (HD) patients. To evaluate cardiac function and the effects of fluid and solute removal during a single session of HD, colour tissue velocity imaging (TVI) was used. This new technique, which is less load dependent than conventional echocardiography, allows an objective quantitative assessment of myocardial contractility, contraction and relaxation.

    Methods. Conventional echocardiographic and TVI images were recorded before and after a single HD session in 13 clinically stable HD patients (62 +/- 10 years, six males) and in 13 sex- and age-matched healthy controls. Myocardial tissue velocities (v; cm/s) for isovolumetric contraction (IVC), peak systole (PS), early (E) and late (A') diastolic filling and strain rate (SR) were measured.

    Results. Left ventricular hypertrophy (LVH) was present in 12 patients. TVI gave additional information in comparison with conventional echocardiography. Before HD, PS (5.0 +/- 0.8 vs 6.0 +/- 1.2 cm/s, P < 0.05), E' (5.7 +/- 1.7 vs 7.3 +/- 2.0 cm/s, P < 0.05) and A' (6.6 +/- 1.7 vs. 8.3 +/- 2.9 cm/s, P < 0.05) velocities were lower in the patients than in the controls, indicating systolic and diastolic dysfunction. The HD session increased IVCv (4.0 +/- 1.7 to 5.5 +/- 1.9 cm/s; P < 0.001), PSv (5.0 +/- 0.8 to 5.7 +/- 0.8 cm/s; P < 0.05) and SR (0.7 +/- 0.2 to 0.9 +/- 0.2 1/s; P < 0.05) and decreased E/E' (16.7 +/- 7.7 to 12.2 +/- 4.0, P < 0.05), indicating improved systolic function and decreased LV filling pressure, respectively. Linear regression analysis demonstrated a dependency of systolic contraction (PSv) and contractility (IVCv) upon plasma levels of phosphate (r(2) = 0.70, P < 0.005, r(2) = 0.33, P < 0.01).

    Conclusions. Using TVI, HD patients demonstrate myocardial dysfunction, which is found less frequently when using conventional echocardiography. The systolic function seems to be impaired by high plasma levels of phosphate and an increased Ca x P product. One single session of HD improved systolic function as indicated by increases in IVCv, PSv and SR. Further studies are needed to clarify if this effect of HD is due to the acute removal of fluid, the removal of solutes or both.

  • 49.
    Hayashi, Shirley Yumi
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lind, Britta
    Department of Clinical Physiology, Karolinska Institutet, Karolinska University Hospital.
    Seeberger, Astrid
    Division of Baxter Novum and Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet.
    Mazza do Nascimento, Marcelo
    Division of Baxter Novum and Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet.
    Lindholm, Bengt J.
    Division of Baxter Novum and Renal Medicine, Department of Clinical Science, Intervention and Technology, Karolinska Institutet.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Analysis of mitral annulus motion measurements derived from M-mode, anatomic M-mode, tissue Doppler displacement, and 2-dimensional strain imaging2006In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 19, no 9, p. 1092-1101Article in journal (Refereed)
    Abstract [en]

    Background: Left ventricular longitudinal shortening plays an important role in cardiac contraction and can be measured by the mitral annulus motion (MAM) toward the cardiac apex. MAM can be evaluated by conventional M-mode, anatomic M-mode (AM-mode), tissue Doppler displacement (TDD), and 2-dimensional strain imaging (2DSI). Objective: The aim of the study was to compare these 4 different methods for measuring MAM. Methods: MAM was evaluated in 25 patients by M-mode, AM-mode, TDD, and 2DSI. Two walls (septal and lateral) in apical 4-chamber view were analyzed. Results. The angle correction between M-mode and AM-mode was significantly higher in the lateral wall (septum 2.2+/-1.6 vs lateral 4.1+/-1.6 degrees, P<0.01). However, with angle correction up to 8 degrees, the measurements obtained were not significantly different from those obtained by M-mode. No significant differences were found among 2DSI. M-mode, and AM-mode either, although all of them were significantly higher in comparison with TDD measurements in both septal (M-mode [11.0 +/- 2.4 nun], AM-mode [11.8 +/- 2.4 mm], 2DSI [11.0 +/- 3.4 mm] vs TDD [9.2 +/- 3.3 mm], P<.01) and lateral (M-mode [11.9 +/- 2.3 min], AM-mode [12.4 +/- 2.8 mm], 2DSI [10.4 +/- 3.9 mm] vs TDD [8.9 +/- 3.0 mm], P<.05) walls. The +/- 2SD variation from the mean difference in septal and lateral walls were, respectively, between: M-mode and TDD, -2.4 to 5.9 and -2.2 to 8.2 mm; M-mode and 2DSI, -5.7 to 5.7 and -5.8 to 8.7; AM-mode and TDD, -2.5 to 5.6 and -2.7 to 9.6; AM-mode and 2DSI, -5.7 to 5.87 and -5.9 to 9.8 and TDD and 2DSI, -3.2 to 6.6 and -5.3 to 8.4. Conclusions: AM-mode and M-mode measurements did not differ significantly. Despite the good correlation among all methods they were not interchangeable. TDD measurements were significantly lower than M-mode, AM-mode, and 2DSI measurements. M-mode and AM-mode are angle dependent and can, therefore, underestimate or overestimate MAM. The new method of 2DSI is promising because it tracks natural acoustic markers and is not angle dependent and, therefore, measures the true local tissue motion.

  • 50.
    Hayashi, Shirley Yumi
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering. Karolinska University Hospital Huddinge, Stockholm, Sweden .
    Nowak, Jacek
    Lindholm, Bengt
    do Nascimento, Marcelo Mazza
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Pachaly, Maria Aparecida
    Seeberger, Astrid
    Riella, Miguel C.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Left ventricular mechanical dyssynchrony in patients with different stages of chronic kidney disease and the effects of hemodialysis2013In: Hemodialysis International, ISSN 1492-7535, E-ISSN 1542-4758, Vol. 17, no 3, p. 346-358Article in journal (Refereed)
    Abstract [en]

    Left ventricular (LV) dyssynchrony is a known cause of mortality in patients with heart failure and may possibly play a similar role in patients with chronic kidney disease (CKD) in whom sudden death is one of the most common and as yet not fully explained cause of death. LV synchronicity and its relationship with increased volume load and various biomarkers was analyzed in 145 patients including 53 patients with CKD stages 3 and 4 and in 92 CKD stage 5 patients undergoing hemodialysis (HD) or peritoneal dialysis (PD) using color tissue Doppler imaging and tissue synchronization imaging. The HD patients were evaluated both before and after a single HD session. LV dyssynchrony was defined as a regional difference in time to peak systolic myocardial velocity, between 12 LV segments>105milliseconds. LV dyssynchrony was present in 54% of the patients with no difference between CKD 3 and 4 (58%), HD (48%), and PD (51%). LV dyssynchrony was independently associated with LV mass index and increased estimation of LV end-diastolic pressure. A single HD session resulted in significant changes in LV synchronicity variableswith improvement in 50% of the patientsespecially in patients with higher myocardial systolic velocities and lower LV mass index. Abnormalities in LV synchronicity are highly prevalent in CKD patients already prior to dialysis treatment and are associated with LV hypertrophy, LV dysfunction and load conditions, underlining the importance of volume status for LV synchronicity in CKD patients.

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