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Myocardial Velocities (myocardial + velocity)
Selected AbstractsQuantitative Assessment of Regional Right Ventricular Myocardial Velocities in Awake Dogs by Doppler Tissue Imaging: Repeatability, Reproducibility, Effect of Body Weight and Breed, and Comparison with Left Ventricular Myocardial VelocitiesJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2005Valérie Chetboul Right ventricular myocardial (RVM) motion is poorly documented. The objective of this study was to determine the variability of RVM velocities by tissue Doppler imaging (TDI) in healthy dogs (study 1), to analyze RVM motion in a large healthy canine population (study 2), and to compare the results with those obtained for the left ventricular free wall. Six healthy Beagle Dogs were monitored in study 1, and 64 healthy dogs of 14 different breeds were monitored in study 2. Velocities were recorded in 2 segments (basal and apical) of the right and left myocardial walls. In study 1, 36 TDI examinations were performed for 4 days, whereas a single TDI examination was performed on each dog in study 2. All velocity profiles included 1 positive systolic wave and 2 negative diastolic waves. The lowest intraday and interday coefficient of variation values of the right TDI variables were observed at the base (3.5,16.1%). The variability of the right apical velocities was much higher, with most coefficient of variation values >15%. RVM velocities were higher in the basal than in the apical segments (P < .001) and were higher than the left velocities of the corresponding segment (P < .01). Body weight and breed had an effect on only a few right and left TDI variables. TDI provides a repeatable and reproducible method for evaluating basal RV function in the dog. These data also demonstrate the heterogeneity of the myocardial velocities between the left and the right ventricles and between the base and the apex. [source] "Supranormal" Cardiac Function in Athletes Related to Better Arterial and Endothelial FunctionECHOCARDIOGRAPHY, Issue 6 2010Maria Florescu M.D. Objective: Athlete's heart is associated with left ventricular (LV) hypertrophy (LVH), and "supranormal" cardiac function, suggesting that this is a physiological process. Hypertrophy alone cannot explain increase in cardiac function, therefore, other mechanisms, such as better ventriculo-arterial coupling might be involved. Methods: We studied 60 male (21 ± 3 years) subjects: 27 endurance athletes, and a control group of 33 age-matched sedentary subjects. We assessed global systolic and diastolic LV function, short- and long-axis myocardial velocities, arterial structure and function and ventriculo-arterial coupling, endothelial function by flow-mediated dilatation, and amino-terminal pro-brain natriuretic peptide (NT-proBNP) and biological markers of myocardial fibrosis and of oxidative stress. Results: Athletes had "supranormal" LV longitudinal function (12.4 ± 1.0 vs 10.1 ± 1.4 cm/s for longitudinal systolic velocity, and 17.4 ± 2.6 vs 15.1 ± 2.4 cm/s for longitudinal early diastolic velocity, both P < 0.01), whereas ejection fraction and short-axis function were similar to controls. Meanwhile, they had better endothelial function (16.7 ± 7.0 vs 13.3 ± 5.3%, P < 0.05) and lower arterial stiffness (pulse wave velocity 7.1 ± 0.6 vs 8.8 ± 1.1 m/s, P = 0.0001), related to lower oxidative stress (0.259 ± 0.71 vs 0.428 ± 0.88 nmol/mL, P = 0.0001), with improved ventriculo-arterial coupling (37.1 ± 21.5 vs 15.5 ± 13.4 mmHg.m/s3× 103, P = 0.0001). NT-proBNP and markers of myocardial fibrosis were not different from controls. LV longitudinal function was directly related to ventriculo-arterial coupling, and inversely related to arterial stiffness and to oxidative stress. Conclusions: "Supranormal" cardiac function in athletes is due to better endothelial and arterial function, related to lower oxidative stress, with optimized ventriculo-arterial coupling; athlete's heart is purely a physiological phenomenon, associated with "supranormal" cardiac function, and there are no markers of myocardial fibrosis. (Echocardiography 2010;27:659-667) [source] Left and Right Ventricular Function Is Impaired in Behçet's DiseaseECHOCARDIOGRAPHY, Issue 9 2006Bunyamin Yavuz M.D. Objectives: Subclinical cardiac involvement may occur in patients with Behçet's disease (BD). The purpose of our study was to assess the noninvasive parameters of biventricular function derived from Doppler tissue imaging (DTI) of the tricuspid and mitral annular motion in BD. Methods: Twenty-one patients with BD and 20 control subjects were enrolled in this study. All subjects were selected to exclude those with cardiovascular risk factors. Standard echocardiography and pulsed DTI were obtained in every patient. Results: Peak systolic (13.71 ± 2.09 vs 20.01 ± 1.57, P < 0.001), peak early diastolic (11.26 ± 2.52 vs 15.35 ± 2.06, P < 0.001) tricuspid annular velocities were significantly lower in patients than controls. Peak systolic (8.68 ± 1.4 vs 12.25 ± 1.7, P < 0.001), peak early diastolic (7.89 ± 1.07 vs 9.94 ± 1.12, P < 0.001), and peak end diastolic (8.30 ± 1.32 vs 9.23 ± 0.91, P = 0.013) lateral mitral annular velocities were significantly lower in patients than controls. Conclusions: We demonstrated that myocardial velocities, were affected in patients with BD. Therefore, we conclude that right and left ventricular function is impaired in patients with BD. [source] Regional Response of Myocardial Acceleration During Isovolumic Contraction During Dobutamine Stress Echocardiography: A Color Tissue Doppler Study and Comparison with Angiocardiographic FindingsECHOCARDIOGRAPHY, Issue 10 2005Linda B. Pauliks M.D. Background: Color tissue Doppler imaging permits noninvasive quantitation of regional wall motion. In experimental studies, a new marker, the slope of the isovolumic contraction wave, isovolumic acceleration (IVA) was more insensitive to ventricular loading conditions than myocardial velocities. This study compared the regional response IVA to dobutamine stress echocardiography to angiographic findings. Methods: The Myocardial Doppler in Stress Echocardiography (MYDISE) study prospectively recruited 149 consecutive patients with chest pain for dobutamine stress tissue Doppler echocardiography prior to coronary angiography. This color tissue Doppler database was analyzed for IVA in 1192 basal and mid segments at rest and again at peak stress. Angiographic findings were compared to IVA and peak systolic velocities (PSV) in corresponding cardiac segments. The diagnostic accuracy of IVA to predict coronary artery stenosis was determined using cut-off values for three representative segments and with the MYDISE diagnostic model including eight segments. Results: Regional IVA increased in a dose-dependent manner during dobutamine infusion. The response was blunted in the supply territory of stenosed coronary artery branches. IVA performed slightly better than PSV as single marker for coronary artery stenosis. A diagnostic model incorporating IVA and PSV was 85,95% accurate (area under receiver operating characterstic curves). Conclusions: Regional changes of isovolumic acceleration during dobutamine stress echocardiography reflect regional wall motion and can be used to predict coronary artery stenosis with similar accuracy as a model based on systolic myocardial velocities. As a single marker, IVA performed better than myocardial velocities. (ECHOCARDIOGRAPHY, Volume 22, November 2005) [source] Effect of Angular Error on Tissue Doppler Velocities and StrainECHOCARDIOGRAPHY, Issue 7 2003Camilla Storaa M.S. One of the major criticisms of ultrasound Doppler is its angle dependency, that is its ability to measure velocity components directly to or from the transducer only. The present article aims to investigate the impact of this angular error in a clinical setting. Apical two- and four-chamber views were recorded in 43 individuals, and the myocardium was marked by hand in each image. We assume that the main direction of the myocardial velocities is longitudinal and correct for the angular error by backprojecting measured velocities onto the longitudinal direction drawn. Strain was calculated from both corrected and uncorrected velocities in 12 segments for each individual. The results indicate that the difference between strain values calculated from corrected and uncorrected velocities is insignificant in 5 segments and within a decimal range in 11 segments. The biggest difference between measured and corrected strain values was found in the apical segments. Strain is also found to be more robust against angular error than velocities because the difference between corrected and uncorrected values is smaller for strain. Considering that there are multiple sources of noise in ultrasound Doppler measurements, the authors conclude that the angular error has so little impact on longitudinal strain that correction for this error can safely be omitted. (ECHOCARDIOGRAPHY, Volume 20, October 2003) [source] Quantitative Assessment of Regional Right Ventricular Myocardial Velocities in Awake Dogs by Doppler Tissue Imaging: Repeatability, Reproducibility, Effect of Body Weight and Breed, and Comparison with Left Ventricular Myocardial VelocitiesJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 6 2005Valérie Chetboul Right ventricular myocardial (RVM) motion is poorly documented. The objective of this study was to determine the variability of RVM velocities by tissue Doppler imaging (TDI) in healthy dogs (study 1), to analyze RVM motion in a large healthy canine population (study 2), and to compare the results with those obtained for the left ventricular free wall. Six healthy Beagle Dogs were monitored in study 1, and 64 healthy dogs of 14 different breeds were monitored in study 2. Velocities were recorded in 2 segments (basal and apical) of the right and left myocardial walls. In study 1, 36 TDI examinations were performed for 4 days, whereas a single TDI examination was performed on each dog in study 2. All velocity profiles included 1 positive systolic wave and 2 negative diastolic waves. The lowest intraday and interday coefficient of variation values of the right TDI variables were observed at the base (3.5,16.1%). The variability of the right apical velocities was much higher, with most coefficient of variation values >15%. RVM velocities were higher in the basal than in the apical segments (P < .001) and were higher than the left velocities of the corresponding segment (P < .01). Body weight and breed had an effect on only a few right and left TDI variables. TDI provides a repeatable and reproducible method for evaluating basal RV function in the dog. These data also demonstrate the heterogeneity of the myocardial velocities between the left and the right ventricles and between the base and the apex. [source] Segmental Differences of Impaired Diastolic Relaxation Following Cardiopulmonary Bypass Surgery in Children: A Tissue Doppler StudyARTIFICIAL ORGANS, Issue 11 2009Linda B. Pauliks Abstract Impaired myocardial relaxation is an important aftereffect of cardiopulmonary bypass (CPB). Infants with their immature calcium metabolism may be particularly vulnerable. However, it has been difficult to quantitate diastolic dysfunction clinically. This study used tissue Doppler to measure regional diastolic myocardial velocities in 31 pediatric patients undergoing open heart surgery. Color tissue Doppler images were acquired in the operating room before and 8 and 24 h post CPB surgery. Early (E) and atrial (A) diastolic velocities were determined. Long axis motion was assessed from apical views near the mitral and tricuspid rings and radial wall motion from the parasternal view. The study included 31 children aged 3.6 ± 4.4 years (6 days to 16 years), with a mean weight of 14.7 ± 13.7 kg and body surface area of 0.59 ± 0.35 m2. Tissue Doppler analysis of regional wall motion revealed abnormal left ventricle (LV) and right ventricle (RV) diastolic relaxation in the early postoperative phase after CPB. Initially, all segments were significantly altered, but by 24 h, regional differences became apparent: LV radial wall motion was recovered, while longitudinal fibers in LV and RV appeared to be less resilient. RV myocardial mechanics were most abnormal. Tissue Doppler analysis may deepen our understanding of myocardial recovery and offers a sensitive tool to compare different cardioprotective strategies. [source] Evaluation of Biventricular Functions With Tissue Doppler Imaging in Patients With Myotonic DystrophyCLINICAL CARDIOLOGY, Issue 3 2010Tolga Ozyigit MD Background: Myotonic dystrophy (MD) is characterized by myotonia with dystrophic involvement of the muscles. Cardiac involvement is usually not evident in the early stages of MD. Hypothesis: We investigated biventricular functions by tissue Doppler imaging (TDI) in MD patients with no overt cardiac involvement to explore the value of TDI in the early detection of myocardial dysfunction. Methods: A total of 21 MD patients (15 male, age: 32.2 ± 12.3 yrs) and 21 healthy controls (13 male, age: 32.2 ± 7.8 yrs) were included. In addition to conventional echocardiography, pulsed Doppler and TDI were performed including measurement of myocardial performance index (MPI); peak systolic (Sm) and early (Em) and atrial (Am) diastolic myocardial velocities at the basal mitral and tricuspid annulus. Results: All patients and controls had normal ejection fraction. Transmitral E peak velocity was significantly lower while both deceleration time of E velocity and isovolumic relaxation time were significantly longer in MD patients (P = 0.007, P = 0.001, and P < 0.001, respectively). Sm, Em and Am peak velocities were significantly lower in MD patients in all segments except for Em of the mitral anterior annulus and Am of the tricuspid lateral annulus. Both left and right ventricular MPI were significantly higher in MD patients (P < 0.001 and P = 0.013, respectively). Conclusion: There are changes in myocardial systolic and diastolic functions in MD patients although they have no overt heart failure. Myocardial tissue velocities and MPI are useful in identifying subclinical biventricular involvement in these patients. Copyright © 2010 Wiley Periodicals, Inc. [source] Right ventricular myocardial isovolumic relaxation time and pulmonary pressureCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2006Pulsed Doppler tissue imaging in resurrection of Burstin's nomogram Summary Aims:, Non-invasive assessment of pulmonary artery systolic pressure (PASP) has several limitations. As previously described by Burstin, the right ventricular (RV) isovolumic relaxation time (IVRt) is sensitive to changes in PASP. We therefore compared RV myocardial IVRt, derived by Doppler tissue imaging (DTI), with simultaneously measured invasive PASP. Methods and results:, Twenty-six consecutive patients (18 males, mean age 52 ± 12 years, range 23,75) underwent a simultaneous Doppler echocardiography, including DTI, and cardiac catheterization examination for measurement of PASP and right atrial mean pressures. IVRt was measured using the myocardial velocities by pulsed DTI at both basal and mid cavity segments of the RV free wall. As diastolic time intervals are influenced by heart rate IVRt was corrected for heart rate (IVRt/RR%). A significant correlation was found between PASP and regional IVRt/RR% at both the basal (r = 0·42, P<0·05) and mid cavity segment (r = 0·71, P<0·001). Furthermore, when only patients with normal right atrial pressures (<7 mmHg) were taken into account, the correlation coefficient improved at both basal and mid cavity segments (r = 0·74, P<0·05 and r = 0·83, P<0·01). Conclusion:, Pulsed Doppler-derived IVRt correlates well with PASP. The use of pulsed DTI for measurement of IVRt is simple, reproducible and easy to obtain. We propose this method as an additional non-invasive tool in the assessment of PASP. [source] Assessment of left ventricular systolic function using tissue Doppler imaging in children after successful repair of aortic coarctationCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 1 2010Tomasz Florianczyk Summary Aim:, Assessment of left ventricular systolic function in children after the successful repair of aortic coarctation using tissue Doppler imaging (TDI). Methods:, The study group consisted of 32 patients (mean age 12·0 ± 4·2 years) after the aortic coarctation repair. The TDI parameters and the conventional echocardiographic endocardial and midwall indices of the left ventricular systolic function were analysed and compared with the results obtained from 34 healthy children. Results:, The systolic mitral annulus motion velocity, systolic myocardial velocity of the medial segment of the left ventricular septal wall, left ventricular strain and Strain Rate (SR) in the study group were significantly higher than in the control group, respectively: 6·92 ± 0·75 cm s,1 versus 6·45 ± 0·83 cm s,1; 5·82 ± 1·03 cm s,1 versus 5·08 ± 1·11 cm s,1; ,28·67 ± 6·04% versus ,22·53 ± 6·44% and ,3·20 ± 0·76 s,1 versus ,2·39 ± 0·49 s,1. Except midwall shortening fraction the conventional endocardial and midwall echocardiographic indices in the study group were significantly higher in comparison to the healthy controls. The left ventricular systolic meridional fibre stress and end-systolic circumferential wall stress did not differ between the examined groups. There were no differences of the TDI or conventional parameters between hypertensive and normotensive patients. Conclusions:, Left ventricular systolic performance in children after the surgical repair of aortic coarctation reveals tendency to rise in late follow-up despite a satisfactory result after surgery. Higher systolic strain and SR in children treated due to coarctation of the aorta may suggest the increased preserved left ventricular performance despite normalization of afterload. [source] | ||||||||||