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  • 1.
    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.

  • 2.
    Hashemi, Nashmil
    et al.
    Karolinska Inst, Danderyd Univ Hosp, Dept Clin Sci, Unit Cardiol, Stockholm, Sweden.;Capio St Gorans Hosp, Dept Clin Physiol, Stockholm, Sweden..
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Gomes-Bernardes, Andrei A.
    Capio St Gorans Hosp, Dept Clin Physiol, Stockholm, Sweden..
    Sartipy, Ulrik
    Karolinska Univ Hosp, Heart & Vasc Theme, Stockholm, Sweden.;Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden..
    Svenarud, Peter
    Karolinska Univ Hosp, Heart & Vasc Theme, Stockholm, Sweden.;Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden..
    Dalen, Magnus
    Karolinska Univ Hosp, Heart & Vasc Theme, Stockholm, Sweden.;Karolinska Inst, Dept Mol Med & Surg, Stockholm, Sweden..
    Back, Magnus
    Karolinska Univ Hosp, Dept Cardiol, Stockholm, Sweden..
    Alam, Mahbubul
    Karolinska Inst, Danderyd Univ Hosp, Dept Clin Sci, Unit Cardiol, Stockholm, Sweden..
    Winter, Reidar
    Karolinska Inst, Danderyd Univ Hosp, Dept Clin Sci, Unit Cardiol, Stockholm, Sweden..
    Right ventricular mechanics and contractility after aortic valve replacement surgery: a randomised study comparing minimally invasive versus conventional approach2018In: Open heart, E-ISSN 2053-3624, Vol. 5, no 2, article id UNSP e000842Article in journal (Refereed)
    Abstract [en]

    Objective Minimally invasive aortic valve replacementsurgery (MIAVR) is an alternative surgical technique to conventional aortic valve replacement surgery (AVR) in selected patients. The randomised study Cardiac Function after Minimally Invasive Aortic Valve Implantation (CMILE) showed that right ventricular (RV) longitudinal function was reduced after both MIAVR and AVR, but the reduction was more pronounced following AVR. However, postoperative global RV function was equally impaired in both groups. The purpose of this study was to explore alterations in RV mechanics and contractility following MIAVR as compared with AVR. Methods A predefined post hoc analysis of CMILE consisting of 40 patients with severe aortic valve stenosis who were eligible for isolated surgical aortic valve replacement were randomised to MIAVR or AVR. RV function was assessed by echocardiography prior to surgery and 40 days post-surgery. Results Comparing preoperative to postoperative values, RV longitudinal strain rate was preserved following MIAVR (-1.5 +/- 0.5 vs -1.5 +/- 0.4 1/s, p=0.84) but declined following AVR (-1.7 +/- 0.3 vs -1.4 +/- 0.3 its, p<0.01). RV longitudinal strain reduced following AVR (-27.4 +/- 2.9% vs -18.8%+/- 4.7%, p<0.001) and MIAVR (-26.5 +/- 5.3% vs -20.7%+/- 4.5%, p<0.01). Peak systolic velocity of the lateral tricuspid annulus reduced by 36.6% in the AVR group (9.3 +/- 2.1 vs 5.9 +/- 1.5 cm/s, p<0.01) and 18.8% in the MIAVR group (10.1 +/- 2.9 vs 8.2 +/- 1.4 cm/s, p<0.01) when comparing preoperative values with postoperative values. Conclusions RV contractility was preserved following MIAVR but was deteriorated following AVR. RV longitudinal function reduced substantially following AVR. A decline in RV longitudinal function was also observed following MIAVR, however, to a much lesser extent.

  • 3.
    Herling, L.
    et al.
    Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Dept Obstet & Gynecol, Ctr Fetal Med, Stockholm, Sweden..
    Johnson, Jonas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems. Karolinska Univ Hosp, Dept Obstet & Gynecol, Ctr Fetal Med, Stockholm, Sweden..
    Ferm-Widlund, K.
    Karolinska Univ Hosp, Dept Obstet & Gynecol, Ctr Fetal Med, Stockholm, Sweden..
    Bergholm, F.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Elmstedt, N.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Lindgren, P.
    Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Dept Obstet & Gynecol, Ctr Fetal Med, Stockholm, Sweden..
    Sonesson, S. -E
    Acharya, G.
    Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Dept Obstet & Gynecol, Ctr Fetal Med, Stockholm, Sweden.;UiT Arctic Univ Norway, Dept Clin Med, Womens Hlth & Perinatol Res Grp, Tromso, Norway..
    Westgren, M.
    Karolinska Inst, Dept Clin Sci Intervent & Technol CLINTEC, Stockholm, Sweden.;Karolinska Univ Hosp, Dept Obstet & Gynecol, Ctr Fetal Med, Stockholm, Sweden..
    Automated analysis of fetal cardiac function using color tissue Doppler imaging in second half of normal pregnancy2019In: Ultrasound in Obstetrics and Gynecology, ISSN 0960-7692, E-ISSN 1469-0705, Vol. 53, no 3, p. 348-357Article in journal (Refereed)
    Abstract [en]

    Objectives Color tissue Doppler imaging (cTDI) is a promising tool for the assessment of fetal cardiac function. However, the analysis of myocardial velocity traces is cumbersome and time-consuming, limiting its application in clinical practice. The aim of this study was to evaluate fetal cardiac function during the second half of pregnancy and to develop reference ranges using an automated method to analyze cTDI recordings from a cardiac four-chamber view. Methods This was a cross-sectional study including 201 normal singleton pregnancies between 18 and 42weeks of gestation. During fetal echocardiography, a four-chamber view of the heart was visualized and cTDI was performed. Regions of interest were positioned at the level of the atrioventricular plane in the left ventricular (LV), right ventricular (RV) and septal walls of the fetal heart, to obtain myocardial velocity traces that were analyzed offline using the automated algorithm. Peak myocardial velocities during atrial contraction (Am), ventricular ejection (Sm) and rapid ventricular filling, i. e. early diastole (Em), as well as the Em/Am ratio, mechanical cardiac time intervals and myocardial performance index (cMPI) were evaluated, and gestational age-specific reference ranges were constructed. Results At 18 weeks of gestation, the peak myocardial velocities, presented as fitted mean with 95% CI, were: LV Am, 3.39 (3.09-3.70) cm/s; LV Sm, 1.62 (1.46-1.79) cm/s; LV Em, 1.95 (1.75-2.15) cm/s; septal Am, 3.07 (2.80-3.36) cm/s; septal Sm, 1.93 (1.81-2.06) cm/s; septal Em, 2.57 (2.32-2.84) cm/s; RV Am, 4.89 (4.59-5.20) cm/s; RV Sm, 2.31 (2.16-2.46) cm/s; and RV Em, 2.94 (2.69-3.21) cm/s. At 42weeks of gestation, the peak myocardial velocities had increased to: LV Am, 4.25 (3.87-4.65) cm/s; LV Sm, 3.53 (3.19-3.89) cm/s; LV Em, 4.55 (4.18-4.94) cm/s; septal Am, 4.49 (4.17-4.82) cm/s; septal Sm, 3.36 (3.17-3.55) cm/s; septal Em, 3.76 (3.51-4.03) cm/s; RV Am, 6.52 (6.09-6.96) cm/s; RV Sm, 4.95 (4.59-5.32) cm/s; and RV Em, 5.42 (4.99-5.88) cm/s. The mechanical cardiac time intervals generally remained more stable throughout the second half of pregnancy, although, with increased gestational age, there was an increase in duration of septal and RV atrial contraction, LV pre-ejection and septal and RV ventricular ejection, while there was a decrease in duration of septal postejection. Regression equations used for the construction of gestational age-specific reference ranges for peak myocardial velocities, Em/Am ratios, mechanical cardiac time intervals and cMPI are presented. Conclusion Peak myocardial velocities increase with gestational age, while the mechanical time intervals remain more stable throughout the second half of pregnancy. Using an automated method to analyze cTDI-derived myocardial velocity traces, it was possible to construct reference ranges, which could be used in distinguishing between normal and abnormal fetal cardiac function.

  • 4.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    The Cardiac State Diagram: A new method for assessing cardiac mechanics2015Doctoral thesis, comprehensive summary (Other academic)
  • 5.
    Johnson, Jonas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Håkansson, Felicia
    Shahgaldi, Kambiz
    KTH, School of Technology and Health (STH), Medical Engineering.
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering.
    Norman, Mikael
    Sahlén, Anders
    Impact of tachycardia and sympathetic stimulation by cold pressor test on cardiac diastology and arterial function in elderly females2013In: American Journal of Physiology. Heart and Circulatory Physiology, ISSN 0363-6135, E-ISSN 1522-1539, Vol. 304, no 7, p. H1002-H1009Article in journal (Refereed)
    Abstract [en]

    Johnson J, Hakansson F, Shahgaldi K, Manouras A, Norman M, Sahlen A. Impact of tachycardia and sympathetic stimulation by cold pressor test on cardiac diastology and arterial function in elderly females. Am J Physiol Heart Circ Physiol 304: H1002-H1009, 2013. First published January 25, 2013; doi:10.1152/ajpheart.00837.2012.-Abnormal vascular-ventricular coupling has been suggested to contribute to heart failure with preserved ejection fraction in elderly females. Failure to increase stroke volume (SV) during exercise occurs in parallel with dynamic changes in arterial physiology leading to increased afterload. Such adverse vascular reactivity during stress may reflect either sympathoexcitation or be due to tachycardia. We hypothesized that afterload elevation induces SV failure by transiently attenuating left ventricular relaxation, a phenomenon described in animal research. The respective roles of tachycardia and sympathoexcitation were investigated in n = 28 elderly females (70 +/- 4 yr) carrying permanent pacemakers. At rest, during atrial tachycardia pacing (ATP; 100 min(-1)) and during cold pressor test (hand immersed in ice water), we performed Doppler echocardiography (maximal untwist rate analyzed by speckle tracking imaging of rotational mechanics) and arterial tonometry (arterial stiffness estimated as augmentation index). Estimation of arterial compliance was based on an exponential relationship between arterial pressure and volume. We found that ATP produced central hypovolemia and a reduction in SV which was larger in patients with stiffer arteries (higher augmentation index). There was an associated adverse response of arterial compliance and vascular resistance during ATP and cold pressor test, causing an overall increase in afterload, but nonetheless enhanced maximal rate of untwist and no evidence of afterload-dependent failure of relaxation. In conclusion, tachycardia and cold provocation in elderly females produces greater vascular reactivity and SV failure in the presence of arterial stiffening, but SV failure does not arise secondary to afterload-dependent attenuation of relaxation.

  • 6.
    Johnson, Jonas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering. Karolinska Institute, Sweden.
    Bergholm, Fredrik
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Brodin, Lars Åke
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Agewall, S.
    Henareh, L.
    The early diastolic myocardial velocity: A marker of increased risk in patients with coronary heart disease2014In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 34, no 5, p. 389-396Article in journal (Refereed)
    Abstract [en]

    Objective: Tissue Doppler imaging (TDI) is a promising echocardiographic modality allowing quantification of myocardial performance. However, the prognostic potential of TDI in patients with acute myocardial infarction (AMI) is not yet investigated. We sought to explore the ability of TDI in identifying patients at risk for new cardiovascular events after AMI. Methods: One hundred and nineteen patients with AMI were recruited prospectively (mean age 61 years; range 32-81 years of age). Patients with diabetes mellitus (DM) were excluded. Echocardiography was performed 3-12 months after AMI. Two-dimensional (2-D) and TDI variables were recorded. The patients were followed during a mean period of 4·6 years (range 1-8 years). The primary end-point was defined as any of the following: death from any cause, non-fatal reinfarction or stroke, unstable angina pectoris, congestive heart failure requiring hospitalization and coronary revascularization procedure. Results: Thirty patients had some form of cardiovascular events during follow-up. Seven patients had cardiovascular death, 13 patients had reinfarction and four patients had a stroke. New angina or unstable angina was recorded in 21 patients. Of these patients, 13 underwent percutaneous coronary angioplasty (PCI) or coronary artery bypass grafting (CABG). The early diastolic myocardial velocity (Em) emerged as the only echocardiographic variable that offered a clear differentiation between patients that presented with new cardiovascular (CV) events as compared to the corresponding group without any CV events at follow-up (P&lt;0·05). In multivariate statistical analysis and after adjustment for age, sex, total cholesterol, body mass index (BMI) and other baseline characteristics, Em remained as independent predictors of CV events (HR, 1·18, 95% CI, 1·02-1·36; P&lt;0·05). However, none of the investigated variables evolved as an independent predictor of cardiovascular morbidity and mortality. Conclusion: Em appears to be a sensitive echocardiographic index in identifying non-diabetic patients with AMI at risk of new cardiovascular events.

  • 7.
    Larsson, Matilda
    et al.
    KTH, School of Technology and Health (STH).
    Bjällmark, Anna
    KTH, School of Technology and Health (STH).
    Johnson, Jonas
    KTH, School of Technology and Health (STH).
    Winter, Reidar
    Karolinska Univ Hosp, Dept Clin Physiol, SE-14186 Stockholm, Sweden..
    Brodin, Lars-Ake
    KTH, School of Technology and Health (STH).
    Lundbäck, Stig
    KTH.
    State diagrams of the heart - a new approach to describing cardiac mechanics2009In: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 7, article id 22Article in journal (Refereed)
    Abstract [en]

    Background: Cardiac time intervals have been described as a measure of cardiac performance, where prolongation, shortening and delay of the different time intervals have been evaluated as markers of cardiac dysfunction. A relatively recently developed method with improved ability to measure cardiac events is Tissue Doppler Imaging (TDI), allowing accurate measurement of myocardial movements. Methods: We propose the state diagram of the heart as a new visualization tool for cardiac time intervals, presenting comparative, normalized data of systolic and diastolic performance, providing a more complete overview of cardiac function. This study aimed to test the feasibility of the state diagram method by presenting examples demonstrating its potential use in the clinical setting and by performing a clinical study, which included a comparison of the state diagram method with established echocardiography methods (E/E' ratio, LVEF and WMSI). The population in the clinical study consisted of seven patients with non ST-elevation myocardial infarction (NSTEMI) and seven control subjects, individually matched according to age and gender. The state diagram of the heart was generated from TDI curves from seven positions in the myocardium, visualizing the inter-and intraventricular function of the heart by displaying the cardiac phases. Results: The clinical examples demonstrated that the state diagram allows for an intuitive visualization of pathological patterns as ischemia and dyssynchrony. Further, significant differences in percentage duration between the control group and the NSTEMI group were found in eight of the totally twenty phases (10 phases for each ventricle), e.g. in the transition phases (Pre-Ejection and Post-Ejection). These phases were significantly longer (> 2.18%) for the NSTEMI group than for the control group (p < 0.05). No significant differences between the groups were found for the established echocardiography methods. Conclusion: The test results clearly indicate that the state diagram has potential to be an efficient tool for visualization of cardiac dysfunction and for detection of NSTEMI.

  • 8.
    Maksuti, Elira
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Broomé, Michael
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging. Karolinska Institutet Department of Physiology and Pharmacology.
    Physical modeling of the heart with the atrioventricular plane as a piston unit2013Conference paper (Other academic)
    Abstract [en]

    Cardiac models do not often take the atrioventricular (AV) interactioninto account, even though medicalimaging and clinical studies have shown that the heart pumps with minorouter volume changes throughout the cardiac cycle and with backand forthlongitudinal movements in the AVregion. We present a novel cardiac model based on physical modeling of the heart withthe AV-plane asa piston unit. Model simulationsgeneratedrealistic outputsforpressures and flows as well asAV-piston velocity, emphasizing the relevance of myocardial longitudinal movements in cardiac function

  • 9. Naar, J.
    et al.
    Mortensen, L.
    Winter, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Shahgaldi, K.
    Manouras, A.
    Braunschweig, F.
    Ståhlberg, M.
    Heart rate and dyssynchrony in patients with cardiac resynchronization therapy: a pilot study2017In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 51, no 3, p. 143-152Article in journal (Refereed)
    Abstract [en]

    Objectives: The objective of this pilot study was to describe the impact of paced heart rate on left ventricular (LV) mechanical dyssynchrony in synchronous compared to dyssynchronous pacing modes in patients with heart failure. Methods: Echocardiography was performed in 14 cardiac resynchronization therapy (CRT) patients at paced heart rates of 70 and 90 bpm in synchronous- (CRT), and dyssynchronous (atrial pacing + wide QRS activation) pacing modes. LV dyssynchrony was quantified using the 12-segment standard deviation model (Ts-SD) derived from Tissue Doppler Imaging. In addition, cardiac cycle intervals were assessed using cardiac state diagrams and stroke volume (SV) and filling pressure were estimated. Results: Ts-SD decreased significantly with CRT at 90 bpm (25 ± 12 ms) compared to 70 bpm (35 ± 15 ms, p =.01), but remained unchanged with atrial pacing at different paced heart rates (p =.96). The paced heart rate dependent reduction in Ts-SD was consistent when Ts-SD was indexed to average Ts and systolic time interval. Cardiac state diagram derived analysis of cardiac cycle intervals demonstrated a significant reduction of the pre-ejection interval and an increase in diastole with CRT compared to atrial pacing. SV was maintained at the higher paced heart rate with CRT pacing but decreased with atrial pacing. Discussion: Due to the small sample size in this pilot study general and firm conclusions are difficult to render. However, the data suggest that pacing at higher heart rates acutely reduces remaining LV dyssynchrony during CRT, but not during atrial pacing with dyssynchronous ventricular activation. These results need confirmation in a larger patient cohort.

  • 10. Sahlen, A.
    et al.
    Shahgaldi, Kambiz
    KTH, School of Technology and Health (STH), Medical Engineering.
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Analysis of aortic characteristic impedance in the time domain: validation using computer simulation2012In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 33, p. 138-138Article in journal (Other academic)
  • 11. Sahlen, A.
    et al.
    Shahgaldi, Kambiz
    KTH, School of Technology and Health (STH), Medical Engineering.
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering.
    Winter, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Altered visco-elasticity of common carotid artery of elderly female hypertensives2012In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 33, p. 618-618Article in journal (Other academic)
  • 12. Westholm, C.
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Jernberg, T.
    Winter, Reider
    KTH, School of Technology and Health (STH), Medical Engineering.
    Peak Systolic Velocity (PSV) using colour-coded Tissue Doppler Imaging (TDI) is a strong and independent predictor of outcome in acute coronary syndrome patients2012In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 33, p. 924-924Article in journal (Other academic)
  • 13.
    Westholm, Carl
    et al.
    Karolinska Institute, Sweden.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Gunyeli, Elif
    Karolinska Institute, Sweden.
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering. Karolinska Institute, Sweden.
    Jernberg, Tomas
    Lundbäck, Stig
    Winter, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    The Cardiac State Index (CSI), a new timing-based diagnostic tool foridentifying patients with acute coronary syndromeManuscript (preprint) (Other academic)
  • 14. Westholm, Carl
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Jernberg, Tomas
    Winter, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering.
    The prognostic value of mechanical left ventricular dyssynchrony in patients with acute coronary syndrome2013In: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 11, no 1, p. 35-Article in journal (Refereed)
    Abstract [en]

    Background: Echocardiography is a well-established tool for risk stratification in patients with acute coronary syndrome (ACS). ACS has significant impact on LV dyssynchrony, and detrimental effects on systolic function and long term outcome. The aims of this study were to determine whether LV dyssynchrony carries any predictive information in an unselected ACS population and to evaluate if it has any incremental value to the information given from conventional echocardiographic measurements. Methods: The study included 227 consecutive ACS patients. Primary endpoint was the composite of death, new MI, or rehospitalisation due to heart failure. Dyssynchrony was measured as intersegmental variation of time to peak strain, the post systolic index (PSI) and myocardial performance index (MPI) with the standard deviation and difference between lowest and highest value (delta) expressing the amount of dyssynchrony. Septal-lateral delay was also tested. All dyssynchrony parameters were compared with Ejection fraction (EF). Results: The median follow up time was 53 months. 85 patients reached the combined endpoint. Patients with and without a subsequent combined endpoint differed significantly regarding calculated SD: s and delta-value for PSI, time to peak 2D-strain and MPI but not regarding septal-lateral delay. In ROC-analysis none of the dyssynchrony parameters had larger AUC than EF. When adjusting for traditional risk factors none of the dyssynchrony parameters remained associated with outcome, whereas EF still did. Conclusion: LV dyssynchrony seem to have significant prognostic information in patient with acute coronary syndrome but in comparison to conventional parameters such as EF there is no incremental value of this information.

  • 15. Westholm, Carl
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Sahlen, Anders
    Winter, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering.
    Jernberg, Tomas
    Peak systolic velocity using color-coded tissue Doppler imaging, a strong and independent predictor of outcome in acute coronary syndrome patients2013In: Cardiovascular Ultrasound, ISSN 1476-7120, E-ISSN 1476-7120, Vol. 11, p. 9-Article in journal (Refereed)
    Abstract [en]

    Background: Traditional echocardiographic methods like left ventricular ejection fraction(EF) and wall motion scoring (WMS) and new methods like speckle tracking (ST) based 2D strain carry important prognostic information in acute coronary syndrome (ACS) patients. Parameters from tissue Doppler imaging (TDI), with its high time resolution, may further increase the prognostic value. Peak systolic velocity (PSV) of the basal segments of the left ventricle from TDI is a robust and user independent parameter. The aim was to investigate the prognostic value of PSV compared to EF, WMS, 2D strain and E/e'. Methods: Echocardiographic images were collected and post processed in 227 ACS patients. Additional clinical data was prospectively gathered and patients were followed for 3-5 years regarding the combined endpoint of death or re-admission due to ACS or heart failure. Results: The combined endpoint occurred in 85 (37%) patients. Those with an event had lower median PSV than those without (4,4 cm/s) vs. (5,3 cm/s), (p<0.001). In a ROC analysis, the AUC was larger for PSV (0.75) than for EF (0.68), WMS (0.63), 2D strain (0.67) and E/e'(0.70). The combined endpoint increased with decreasing PSV. When adjusting for differences in baseline characteristics in a COX-regression model, PSV remained independently associated with outcome where the others did not. PSV was also less sensitive to image quality with fewer values missing or unacceptable for analysis. Conclusion: Peak systolic velocity (PSV) is a robust measurement that seems to have a strong and independent association with outcome compared to traditional echocardiographic measurements in ACS patients.

  • 16. Wågström, Elle
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, Kjerstin
    Elmstedt, Nina
    KTH, School of Technology and Health (STH), Medical Engineering.
    Liuba, Karina
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Lundbäck, Stig
    Westgren, Magnus
    The cardiac state diagram as a novel approach for the evaluation of pre- and post-ejection phases of the cardiac cycle in asphyxiated fetal lambs2013In: Ultrasound in Medicine and Biology, ISSN 0301-5629, E-ISSN 1879-291X, Vol. 39, no 9, p. 1682-1687Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to investigate myocardial wall motion using echocardiography and color-coded tissue velocity imaging and to generate a cardiac state diagram for evaluation of the duration of the pre- and post-ejection phases in asphyxiated fetal lambs. Six near-term lambs were partly exteriorized and brought to cardiac arrest through asphyxia. Echocardiography measurements were recorded simultaneously with arterial blood sampling for lactate and blood gases. All fetal lambs exhibited prolongation of the pre- and post-ejection phases at the time when the most pronounced changes in lactate concentration and pH occurred. The mean change in duration of the pre- and post-ejection phases for all fetal lambs was 36 +/- 7 ms (p < 0.002) and 77 +/- 17 ms (p < 0.019), respectively, and the percentage change was 50% (p < 0.001) and 38% (p < 0.049), respectively. As asphyxia progressed in fetal lambs, the duration of the pre- and post-ejection phases increased. The cardiac state diagram has the potential to be a comprehensible tool for detecting fetal asphyxia.

  • 17. Wågström, Elle
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ferm-Widlund, Kjerstin
    Elmstedt, Nina
    KTH, School of Technology and Health (STH), Medical Engineering.
    Liuba, Karina
    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
    The Cardiac State Diagram as a novel approach for evaluation of phases of the cardiac cycle in asfyxiated fetal lambs2012In: Acta Obstetricia et Gynecologica Scandinavica, ISSN 0001-6349, E-ISSN 1600-0412, Vol. 91, p. 144-144Article in journal (Other academic)
  • 18. Zahid, W.
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Westholm, C.
    Eek, C.
    Skulstad, R.
    Fosse, E.
    Winter, Reider
    Edvardsen, T.
    Mitral annular excursion in patients with suspected non-ST-elevation acute coronary syndrome can identify coronary occlusion and predict mortality2012In: European Heart Journal, ISSN 0195-668X, E-ISSN 1522-9645, Vol. 33, p. 912-912Article in journal (Other academic)
  • 19. Zahid, Wasim
    et al.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering.
    Westholm, Carl
    Eek, Christian H.
    Haugaa, Kristina H.
    Smedsrud, Marit Kristine
    Skulstad, Helge
    Fosse, Erik
    Winter, Reidar
    KTH, School of Technology and Health (STH), Medical Engineering.
    Edvardsen, Thor
    Mitral Annular Displacement by Doppler Tissue Imaging May Identify Coronary Occlusion and Predict Mortality in Patients with Non-ST-Elevation Myocardial Infarction2013In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 26, no 8, p. 875-884Article in journal (Refereed)
    Abstract [en]

    Background: Mitral annular displacement (MAD) is a simple marker of left ventricular (LV) systolic function. The aim of this study was to test the hypothesis that MAD can distinguish patients with non-ST-segment elevation myocardial infarctions (NSTEMIs) from those with significant coronary artery disease without infarctions, identify coronary occlusion, and predict mortality in patients with NSTEMIs. MAD was compared with established indices of LV function. Methods: In this retrospective study, 167 patients with confirmed NSTEMIs were included at two Scandinavian centers. Forty patients with significant coronary artery disease but without myocardial infarctions were included as controls. Doppler tissue imaging was performed at the mitral level of the left ventricle in the three apical planes, and velocities were integrated over time to acquire MAD. LV ejection fraction, global longitudinal strain (GLS), and wall motion score index were assessed according to guidelines. Results: MAD and GLS could accurately distinguish patients with NSTEMIs from controls. During 48.6 +/- 12.1 months of follow-up, 22 of 167 died(13%). MAD, LV ejection fraction, and GLS were reduced and wall motion score index was increased among those who died compared with those who survived (P<.001, P<.001, P<.001, and P=.02, respectively). Multivariate Cox proportional-hazards analyses revealed that MAD was an independent predictor of death (hazard ratio, 1.36; 95% confidence interval, 1.07-1.73; P=.01). MAD and GLS were reduced and wall motion score index was increased in patients with coronary artery occlusion compared with those without occlusion (P=.006, P=.001, and P=.02), while LV ejection fraction did not differ (P=.20). Conclusions: MAD accurately identified patients with NSTEMIs, predicted mortality, and identified coronary occlusion in patients with NSTEMIs.

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