二维斑点追踪显像检测三尖瓣环运动评价非梗阻性肥厚型心肌病右室功能的研究

目的 探讨二维斑点追踪显像技术检测三尖瓣环运动在评价肥厚型心肌病（HCM）右室功能中的应用价值.方法 研究对象为38例肥厚型心肌病患者及40例志愿者（对照组）.所有受检者均接受常规超声心动图检查,记录心尖四腔观二维图像并输入Qlab工作站,描绘三尖瓣环间隔部及游离壁处相对于心尖部的运动曲线,测量记录TAD、VS、VE、VA各参数值,并进行对比研究.结果 与对照组相比,HCM患者TAD、VS、VE、VA各参数明显减低,差异有统计学意义.结论 应用二维斑点追踪技术测定三尖瓣环运动有望成为临床常规评价肥厚型心肌病右心室功能的新方法.     

An echocardiographic and magnetic resonance imaging comparative study of right ventricular volume determination

Assessment of right ventricular volume and function is important in many clinical settings involving heart or lung disease. However, the complexity of the right ventricular anatomy has prevented accurate volume determination by two-dimensional echocardiography. In the present study, 5 models incorporating standard echocardiographic views, were used to determine right ventricular volume in 10 human subjects. Two models were contingent on the true crescentic appearance of the right ventricle, whereas the remaining 3 calculated the right ventricular volume as a pyramid, an ellipsoid or other tapering geometrical figures, respectively. Subsequently, echocardiographic right ventricular volumes were compared to magnetic resonance imaging derived volumes. Correlation analysis and agreement measurement between the echocardiographic and magnetic resonance end-diastolic volume were performed in 10 out of 10 subjects and in 9 out of 10 subjects for the end-systolic volume. The 2 crescentic models resulted in the most reliable estimation of right ventricular volume. Those findings suggest that models based on right ventricular anatomical landmarks are feasible and should be preferred in echocradiographic studies.     

Assessment of the normal adult right ventricular diastolic function using M-mode echocardiographic measurement of tricuspid ring motion

Right ventricular function can be evaluated echocardiographically by assessing the longitudinal motion of the tricuspid ring recorded in the apical four chamber view. In this study, we applied this technique to assess the right ventricular diastolic function in 10 healthy Japanese men (mean age : 28±6 years; age range : 20–43 years). Echocardiographic studies were performed with a phased-array imaging system using a 2.5 MHz probe. Tricuspid ring motion was measured by two-dimensional echo guided M-mode echocardiogram of the right lateral tricuspid ring. The excursion of the tricuspid ring during early diastole (dS; mm) and the peak rate of change of the excursion (dS/dt; mm/sec) were measured. We also assessed the right ventricular function by cine magnetic resonance imaging (MRI). Cine gradient echo images were obtained along the short axis of the right ventricle. The right ventricular volume at each phase of the cardiac cycle was calculated by Simpson's method and time–volume curves were constructed. The peak filling rate (dV/dt; ml/s) was determined from these time–volume curves. The dS was 12.8±2.5 mm, dS/dt was 132±27 mm/sec and dV/dt was 269±66 ml/s. There were significant positive correlations between dS and dV/dt (r=0.80, P<0.01), and between dS/dt and dV/dt (r=0.45, P<0.05). Based on our results, M-mode echocardiographic measurements of tricuspid ring motion may be used to assess the right ventricular diastolic function.     

Feasibility of right ventricular longitudinal systolic function evaluation with transthoracic echocardiographic indices derived from tricuspid annular motion: a preliminary study in acute respiratory distress syndrome

Introduction: Assessment of right ventricular (RV) function in patients with acute respiratory distress syndrome (ARDS) remains challenging. Transthoracic echocardiographic (TTE) indices based on longitudinal systolic RV function are now considered as a reliable evaluation of RV function. We investigated feasibility of two methods in ARDS patients. Methods: Prospective observational study. TTE was performed after 12–36 hours of mechanical ventilation. Feasibility of tricuspid annular motion (S_t), tricuspid annular plane systolic excursion (TAPSE) was compared to usual two‐dimensional (2D) study: fractional area change (RV_FAC) and ratio of right to left ventricular end‐diastolic area (RVEDA/LVEDA). Results: Fifty patients were investigated, with TTE possible in all but two patients. Feasibility was 62% for RV_FAC, 72% for RVEDA/LVEDA, and 96% for TAPSE and S_t. RV dilatation (RVEDA/LVEDA ≥0.60) was found in 16 patients, including 4 patients with acute cor pulmonale. A longitudinal RV dysfunction (TAPSE < 12 mm or S_t < 11.5 cm/sec) was suspected in 30% of patients. Relation between both longitudinal indices was modest (r²= 0.36, P < 0.001). TAPSE (but not S_t) was found poorly related to RV_FAC (r²= 0.27, P = 0.03). Both indices were related to LV function (S_t: r²= 0.27, TAPSE: r²= 0.17, both P < 0.05). Conclusion: Despite a superior feasibility than 2D study, our results suggest that both indices may not bring identical information to echo study. TAPSE may be more adapted to ICU use than S_t. Both should be further investigated in terms of analysis of RV function and ventricular interdependence. Their relations with LV function may limit their use as sole markers of RV function in this population. (Echocardiography 2012;29:513‐521)     

Reference values of right atrial longitudinal strain imaging by two-dimensional speckle tracking

Background: The role of speckle tracking in the assessment of right atrial (RA) deformation dynamics has not been established yet. The reference ranges of RA longitudinal strain indices were measured by speckle tracking in a population of normal subjects. Methods: In 84 healthy individuals, peak atrial longitudinal strain (PALS), peak atrial contraction strain (PACS), and time to peak longitudinal strain (TPLS) were measured using a six‐segment model for the RA. Strain rate (SR) was also measured starting from the QRS‐wave onset, peak positive (x‐wave), first peak negative (y‐wave), and second negative peak (z‐wave). The time from the QRS onset was measured to each wave peak. Results: Adequate tracking quality was achieved in 64% of segments analyzed. Inter‐ and intraobserver variability coefficients of measurements ranged between 6% and 11%. Global PALS was 49 ± 13%, global TPLS was 363 ± 59 msec, x‐wave was 2.12 ± 0.58 sec^?1, y‐wave was ?1.91 ± 0.63 sec^?1, and z‐wave was ?2.18 ± 0.78 sec^?1. Conclusion: Speckle tracking is a feasible technique for the assessment of longitudinal myocardial RA deformation. Reference ranges of strain indices were reported. (Echocardiography 2012;29:147‐152)     

Circadian blood pressure pattern and right ventricular and right atrial mechanics: A two- and three-dimensional echocardiographic study

The purpose of this investigation was to evaluate right ventricular (RV) and right atrial (RA) function and mechanics in untreated hypertensive patients with different blood pressure (BP) patterns by using two-dimensional (2DE) speckle tracking analyses and three-dimensional echocardiography (3DE). This cross-sectional study included 174 recently diagnosed hypertensive patients. All patients underwent a 24-hour ambulatory BP monitoring and complete 2DE and 3DE examination, including 2DE speckle tracking analysis. Our results showed that 2DE RV global longitudinal strain was significantly lower in the non-dippers. Similar results were obtained for 2DE RV systolic and early diastolic strain rate. The RA longitudinal strain, as well as RA systolic and early diastolic strain rate, was decreased in non-dippers. Our results revealed that 3DE RV end-diastolic and end-systolic volumes were increased, whereas 3DE RV ejection fraction was reduced in non-dipper hypertensive patients. Similar results were obtained for RA volumes and RA ejection fraction estimated by 2DE. Independent predictors of 3DE RV ejection fraction, 2DE RV and RA global longitudinal strain were left ventricular mass index and RV wall thickness. An additional independent predictor of the RV longitudinal strain was 3DE RV ejection fraction, and for RA longitudinal strain, an additional independent predictor was tricuspid E/é ratio. Two-DE speckle tracking evaluation and 3DE examination revealed that the RV and RA function and mechanics were more deteriorated in the non-dipper patients than in dipper untreated hypertensive patients.     

Risk stratification of patients with Brugada syndrome: the impact of myocardial strain analysis using cardiac magnetic resonance feature tracking

ObjectiveThis study evaluated the prognostic significance of cardiac magnetic resonance myocardial feature tracking (CMR-FT) in patients with Brugada syndrome (BrS) to detect subclinical alterations and predict major adverse events (MAE).MethodsCMR was performed in 106 patients with BrS and 25 healthy controls. Biventricular global strain analysis was assessed using CMR-FT. Patients were followed over a median of 11.6 [8.8 ± 13.8] years.ResultsThe study cohort was subdivided according to the presence of a spontaneous type 1 ECG (sECG) into sBrS (BrS with sECG, n = 34 (32.1%)) and diBrS (BrS with drug-induced type 1 ECG, n = 72 (67.9%)). CMR-FT revealed morphological differences between sBrS and diBrS patients with regard to right ventricular (RV) strain (circumferential (%) (sBrS −7.9 ± 2.9 vs diBrS - 9.5 ± 3.1, p = 0.02) and radial (%) (sBrS 12.0 ± 4.3 vs diBrS 15.4 ± 5.4, p = 0.004)). During follow-up, MAE occurred in 11 patients (10.4%). Multivariable analysis was performed to identify independent predictors for the occurrence of events during follow-up. The strongest predictive value was found for RV circumferential strain (OR 3.2 (95% CI 1.4 - 6.9), p = 0.02) and RVOT/BSA (OR 3.1 (95% CI 1.0 - 7.0), p = 0.03).ConclusionsMyocardial strain analysis detected early subclinical alterations, prior to apparent changes in myocardial function, in patients with BrS. While usual functional parameters were within the normal range, CMR-FT revealed pathological results in patients with an sECG.Moreover, RV circumferential strain and RVOT size provided additional prognostic information on the occurrence of MAE during follow-up, which reflects electrical vulnerability.     

Importance of the echocardiographic evaluation of right ventricular function in patients with AL amyloidosis

BACKGROUND: Patients with AL amyloidosis often present with signs of congestive heart failure. AIM: This study was prospectively designed to assess the significance of RV dysfunction in AL amyloidosis. METHODS AND RESULTS: Seventy-four patients with biopsy proven AL amyloidosis underwent a thorough echocardiographic evaluation. A tricuspid annular plane systolic excursion (TAPSE)<17 mm was taken as marker of RV dysfunction. Plasma NT-proBNP determinations were performed in all cases. RV function was normal in 60 patients and reduced in 14 patients. Patients with RV dysfunction had thicker left ventricular (LV) walls (p<0.01), lower LV end-diastolic volumes (p<0.01), lower LV ejection fraction (p<0.01) and more frequently a restrictive LV filling pattern (p<0.01). RV dimensions and RV free wall thickness were not significantly different in the two groups. A thick interventricular septum and a reduced TAPSE were associated with high NT-proBNP levels (both p<0.01). Seven patients died during a median follow-up period of 19 months; TAPSE<17 mm was the only echocardiographic parameter associated with poor survival. CONCLUSION: In patients with AL amyloidosis, RV dysfunction is associated with more severe involvement of the left ventricle, higher plasma levels of NT-proBNP and with poor prognosis.