Assessment of severity in aortic stenosis – Incremental value of endocardial function parameters compared to standard indexes

Several studies have reported that patients (pts) with severe aortic stenosis and similar pressure gradients or even similar aortic valve areas may have quite different symptomatic status and clinical outcomes suggesting that other factors might have a significant impact on the pathophysiology of this disease. Our purpose was to assess the severity of subendocardial wall dysfunction in symptomatic and asymptomatic pts with aortic stenosis using tissue Doppler imaging (TDI), strain rate imaging (SRI) and cyclic variation of integrated backscatter (IB). We studied 68 pts with aortic valvar stenosis and 46 subjects with no signs of heart disease. SRI/IB indexes were calculated in the apical four chambers views at endocardial level. Early diastolic endocardial strain rate showed the best correlation with transvalvar pressure gradients and valve areas. Compared with controls, symptomatic pts showed a more marked decrease in endocardial strain, strain rate and cyclic variation of IB. Receiver operating characteristic (ROC) curves suggested that the thresholds offering an adequate compromise between sensitivity and specificity for the prediction of symptoms were >/=60 mm Hg for the pressure gradient, less than 0.60 cm(2)/m(2) for aortic valve area, less than 20% for strain, less than 2.0 s(-1) for strain rate and less than 3.0 dB for cyclic variation. The combination of pressure gradient, aortic valve area and SRI/IB parameters resulted in an improvement of the overall performance for predicting the symptomatic state. Thus, SRI/IB parameters have an incremental value in differentiating symptomatic and asymptomatic pts with aortic stenosis compared with conventional hemodynamic parameters

Assessment of ascending aorta distensibility after successful coarctation repair by strain Doppler echocardiography

BACKGROUND: Increased arterial stiffness may participate in the genesis of hypertension and increase of left ventricular (LV) mass after surgical correction of coarctation of the aorta. The purpose of the current study was to assess the aortic elastic properties using Doppler tissue imaging and strain rate imaging in patients after coarctoplasty. METHODS: Echocardiography with Doppler tissue/strain rate imaging capabilities was performed in 26 adult normotensive patients who had successful repair of coarctation of the aorta in infancy and in 24 control subjects. Transesophageal aortic transverse sections were imaged at the level of the proximal and distal segments to the repair site. Doppler tissue imaging wall velocities during systole (S(w)), early relaxation (E(w)), and atrial systole (A(w)) and peak systolic strain (ps epsilon) were measured in both groups. Transthoracic ascending aorta (AAo) measurements were also obtained. RESULTS: In the patients with coarctoplasty, S(w) velocities and ps epsilon were significantly decreased in the proximal segments compared with control subjects. Both peak systolic blood pressure after exercise (P < .001) and pulse pressure after exercise (P < .001) were directly related to AAo wall strain. LV annular early diastolic velocity was significantly reduced compared with control subjects in patients with decreased AAo wall strain and exercise-induced hypertension (P < .001) and related to AAo wall velocity (P < .005) and strain (P < .001). In multiple linear regression analysis, only weight, study group, and AAo wall strain were correlated to LV mass index. CONCLUSIONS: Patients with coarctation of the aorta have reduced proximal aortic wall velocities and strain and increased stiffness even after successful repair. This amplifies stress-induced hypertension and increases LV burden

Analysis of valvar and left ventricular parameters in infective aortic endocarditis as predictors of outcome: a combined assessment by transesophageal and strain echocardiography

Purpose. The timing of surgery is crucial for patients with aortic endocarditis in whom medical therapy fails. The aim of our study is to identify potential echocardiographic "markers" of adverse events in patients with aortic regurgitation from infective endocarditis. Methods. Fifteen patients with aortic regurgitation (AR) from infective endocarditis were studied by transesopageal echocardiography (TEE) and transthoracic speckle tracking echocardiography (STE). Fifteen healthy subjects were selected as controls. Vegetation size was assessed by TEE. Standard transthoracic echocardiographic parameters were determined. Global left ventricular (LV) longitudinal strain (LS), radial and circumferential strain were measured by STE. Averaged LV rotation and rotational velocities from the base and apex were obtained and used for calculation of LV torsion (LVtor). Mitral annular velocities were also obtained by tissue Doppler imaging (TDI). Results. Mean percentage intraobserver variability was 6% for LV-LS and 8% for LV-tor, and mean percentage interobserver variability was 11% for for LV-LS and 12% for LV-tor. Severe AR had decreased LS compared with control subjects. LVtor decreased significantly in severe AR compared to normals (p<.001) as a result of a predominant decrease in apical rotation. By multivariate analysis, LV-LS (p=0.03), LV-tor (p=0.008) and vegetation size (p=0.009) were predictive of adverse events. ROC curves suggested that thresholds offering an adequate compromise between sensitivity and specificity for adverse events detection were -18.4% for mean global LV-LS (AUC .76), 12mm for vegetation size (AUC .84), and 19.7degrees for LVtor (AUC .89). The combination of vegetation size and LVtor had the highest diagnostic accuracy for identifying adverse outcome, superior to vegetation size (p=.008) or LVtor alone (p=.026). Conclusions. The combined evaluation of the characteristics of vegetating masses and LV function strain parameters improve the sensitivity of echocardiographic indices in predicting cardiac morbidity and mortality of aortic regurgitation from infective endocarditis

Differentiation of pathologic forms of cardiac hypertrophy from athlete heart by 2D-strain-Doppler echocardiography

Purpose: Assessment of the underlying etiology of left ventricular hypertrophy (LVH) is a challenging clinical problem. In this study we sought to determine whether tissue Doppler imaging (TDI) and speckle tracking imaging (STI) could distinguish between subjects with pathological LVH, such as occurs in hypertensive heart disease, hypertrophic cardiomyopathy (HCM), or aortic stenosis, and those with athletic LVH. Methods: A total of 113 participants were studied, comprising competitive athletes (25), hypertensive heart disease (25), HCM (12), aortic stenosis (21), and healthy volunteers (30). Left ventricular mass index, ejection fraction, end-diastolic, end-systolic and stroke volume index, diastolic wall thickness, wall thickness ratio and diastolic and systolic wall-to-volume ratios were determined. Peak systolic longitudinal strain (e), peak systolic strain rate (SR-S), peak early diastolic strain rate (SR-E), and peak late diastolic strain rate (SR-A) values were measured by TDI in the basal, mid and apical segments in apical 4-chamber view. Averaged LV rotation and rotational velocities from the base and apex were obtained by STI and used for calculation of LV torsion (LVtor). The analysis of strain Doppler parameters and rotation was performed offline using customized computer software (EchoPac, Version 7.0, General Electric). All of the calculations were averaged for at least 3 consecutive beats. Results: Left ventricular (LV) mass indices were similar for all forms of LVH (p..05), which were higher than those obtained in healthy volunteers (p,.05). Athletes had no significant differences in e and SR-E compared with control subjects (p ¼ .16 and .82, respectively). Patients with pathologic LVH had significantly decreased e and SR-E (average septum: 216.8 + 3.2%, and 1.66 + 0.37 s-1, respectively) comparedwith control subjects (221.9 + 3.5%, and 2.44 + 0.45 s-1, respectively; all p,.0005). LVtor increased significantly in pathologic LVH and in athletes compared to normals (p,.005 and .0001, respectively). In pathologic LVH LVtor increased mainly as a result of reduced basal rotation (23.8+1.3 vs 26.1+1.6 degrees, p¼.04). In athletes the LVtor increase was the result of an increase in both basal and apical rotation (basal rotation, 26.1+1.6 vs 28.9+1.8 degrees, p¼.03; apical rotation, 17.2+3.2 vs 25.9+4.6 degrees, p¼.07). Conclusions: Pathologic LVH has significant longitudinal strain and SR-E reduction versus controls and a different pattern of LV torsion compared to athletes. These findings suggest that TDI and STI may have a clinical impact in the assessment of physiologic LVH state

Assessment of aortic wall mechanics in Marfan syndrome by transesophageal tissue Doppler echocardiography

The aim of this study was to investigate the value of tissue Doppler imaging (TDI) using transesophageal echocardiography (TEE) in assessing the elastic properties of the thoracic aorta in patients with Marfan’s syndrome. Aortic distensibility, stiffness index, and pulse-wave velocity were calculated using M-mode data in a TEE short-axis view in 31 patients with Marfan’s syndrome and 22 normal controls. Acceleration time, maximum wall expansion velocity (Vmax), and wall strain were determined from TDI tracings. Indexes derived from TDI differed at a greater level of significance than M-mode-derived indexes in patients with dilated and normal aortas. Significant predictors of aortic dilation were systolic blood pressure, aortic stiffness index, Vmax, and strain. Decreased aortic strain and Vmax and increased stiffness index were predictive of aortic dissection (odds ratios 4.5, 3.3, and 2.2). In conclusion, the TDI assessment of aortic wall mechanics is complementary to standard M-mode measurements in discriminating normal subjects from patients with Marfan’s syndrome and is accurate in predicting aortic dilation and dissection. Color Doppler myocardial imaging has emerged as a new technique for the assessment of ventricular myocardial velocities and regional ventricular contractility, [1], [2], [3] and [4] and preliminary data suggest its suitability for the evaluation of aortic wall velocities. [5], [6] and [7] This study was performed to assess the potential value of tissue Doppler imaging (TDI) using transesophageal echocardiography (TEE) in evaluating the elastic properties of the ascending and descending thoracic aortas in patients with Marfan’s syndrome and normal controls and in predicting aortic dilation and dissection

Ascending aorta wall distensibility in healthy and hypertensive subjects: assessment by tissue Doppler velocity imaging

Purpose: The stiffening of aorta and other central arteries is a potential risk factor for increased cardiovascular morbidity and mortality. The purpose of this study was to investigate the potential clinical application of tissue Doppler imaging (TDI) for motion measurement of the aortic wall in healthy and hypertensive adults. Methods: We examined 31 hypertensive without a history of coronary artery disease (negative echo-stress test) and 31 age- and sex-matched healthy adults. Arterial pressure was measured with a mercury sphygmomanometer before echocardiography was performed. Pulse wave velocity (PWV) was measured as a standard parameter of arterial stiffness by oscillometric pulse wave analysis system (TensioMed Arteriograph, Hungary). Aortic M-mode and TDI parameters were measured 3 cm above the aortic valve. Aortic distensibility and aortic stiffness index (SI) were calculated using accepted formulae. Maximum velocity of the first and second systolic wall expansion peaks (S, S1,cm/sec), acceleration time (AT, msec), maximum velocity of early (E, cm/sec) and late (L, cm/sec) diastolic retraction velocity peaks of the ascending aorta and wall peak systolic strain (ps-e, %) were determined (EchoPAC, version 7.0, GE Ultrasound). Results: Observational variability was low. In hypertensive patients wall motion waveform showed lacking L, mixed S and S1 peaks, and blunted S compared with controls. S, E and ps-e were significantly lower in hypertensive than in healthy subjects. Reduced PWV and increased SI indicated increased aortic stiffness in both male and female hypertensive subjects. Age, diastolic blood pressure and sex were significant independent factors modulating S, while diastolic blood pressure and age were significant independent factors modulating E. PWV decreased with increasing age or systolic blood pressure. Duration of hypertension correlated with SI (r¼0.57, p,0.005), distensibility (r¼20.54, p,0.005) and S velocity (r¼20.62, p,0.001). There was a negative correlation between aortic stiffness and S velocity (r¼20.51, p,0.005). Multiple stepwise linear regression analysis in the hypertension group revealed that aortic S velocity (b¼0.35, p¼0.006), ps-e (b¼0.38, p¼0.007) and duration of hypertension (b¼20.51, p¼0.001) were the main predictors of aortic distensibility (overall R2 ¼ 0.53). Conclusions: Our data show that TDI measurement of ascending aortic wall motion provides qualitative and quantitative wall motion features differentiating hypertensive from healthy adults and reflecting aortic compliance changes related to age and sex

Triplane tissue Doppler echocardiography and radionuclide angiocardiography in the assessment of ventricular asynchrony in patients with heart failure

Purpose. Several parameters have recently been proposed to assess mechanical dyssynchrony both in tissue Doppler / strain Doppler imaging (TDI/SRI) and radionuclide angioscintigraphy (RNA). It is unknown whether large differences exist between TDI and RNA to evaluate inter- and intra-ventricular dyssynchrony and whether the results are interchangeable. Methods. Thirty-four patients with dilated cardiomyopathy (NYHA class II or greater), left bundle branch block (QRS 120ms), and LV ejection fraction 35% were studied with triplane TDI echocardiography (Vivid 9 ultrasound system, GE, Horten, Norway) and RNA before and after biventricular pacing (BP). Intraventricular dyssynchrony was determined as the difference between the longest and shortest electromechanical coupling times in the basal septal, lateral, and posterior LV segments. Interventricular dyssynchrony was determined as the difference between electromechanical coupling times in the basal lateral RV segment and the most delayed LV segment. On line continuous LV volume changings were recorded using RNA and interventricular delay and basal-apical contraction were obtained. Results. At six months follow-up after BV implantation, patients functional status improved by one NYHA class or more and LVEF improved overall from 20.46.5% to 29.511.1%. Interventricular dyssynchrony by triplane TDI was reduced from 75.729 ms to 32.620.9 ms (p<0.005) and intraventricular dyssynchrony from 7924.7 ms to 28.312.8 ms (p<0.001). Interventricular dyssynchrony by RNA was reduced from 7728 ms to 13.725.3 ms (p<0.001) and apicobasal intraventricular dyssynchrony from 68.626.4 ms to 17.119.2 ms (p<0.001). Triplane TDI and RNA parameters had optimal predictive accuracy of the effects of BP on LV function and a larger area under the receiver operating characteristic curve than the QRS duration. Overall agreement between TDI and RNA was 89% (k= 0.67). Conclusions. Triplane TDI and RNA dyssynchrony measurements have an acceptable observer variability and values are largely comparable in pts with poor LV function and broad QRS

Assessment of constrictive pericarditis by Tissue Doppler Imaging and Speckle Tracking Imaging

Purpose. Constrictive pericarditis (CP) is defined by a thickened, adherent, or calcific pericardium that limits myocardial free wall motion. Although normal or exaggerated early diastolic mitral annular velocity provides high specificity for differentiating CP from restrictive cardiomyopathy (RCM), its sensitivity has been shown to be lower. Our purpose was to assess the incremental value of Tissue Doppler Imaging (TDI) and Speckle Tracking Imaging (STI) for differentiation between CP and RCM. Methods. Eleven patients with CP, 8 with RCM, and 12 control subjects were studied. Standard mitral inflow Doppler and tissue Doppler echocardiography were performed. LV TDI annular peak systolic and diastolic velocities (S’, E’) and time difference between onset of mitral inflow and onset of E' (E'-E time) were measured. LV peak systolic longitudinal strain (l) and systolic and diastolic strain rate were obtained in the basal, mid and apical segments of septal and lateral walls in apical 4-chamber view both by TDI and STI. Transverse strain and averaged LV rotation and rotational velocities from the base and apex were also obtained by STI. Results. E' and S' were significantly higher in patients with CP than RCM (8.9 ± 1.5 vs 4.3 ± 1.4 cm/s, and 7.9 ± 1.1 vs 4.3 ± 1.6 cm/s respectively, p < .001). E'-E was significantly shorter in patients with CP (25.6 ± 21.7 vs 56.6 ± 24.7 ms, p < .005). Impairment of longitudinal strain in the lateral wall was shown (25.6 ± 16.7 vs 56.6 ± 21.3%, p < .005) whereas transverse strain values did not change significantly. ROC curves suggested that the thresholds offering an adequate compromise between sensitivity and specificity for detection of CP were -20% for STI-l (AUC 0.86), -23% for TDI-l (AUC 0.81), 32.6 ms for E’-E time (AUC 0.77), and -5.0 cm/sec for TDI-E’ velocity (AUC 0.73). Conclusions. TDI and STI parameters can be helpful to differentiate between CP and RCM by providing incremental diagnostic information to conventional Doppler echocardiography