Effects of tafamidis on the left ventricular and left atrial strain in patients with wild-type transthyretin cardiac amyloidosis.

AIMS: Although tafamidis is used in patients with wild-type transthyretin cardiac amyloidosis (ATTRwt-CA), its specific effect on cardiac function is unclear. Thus, this study aimed to investigate the effect of tafamidis on left atrial (LA) and left ventricular function using speckle-tracking echocardiography for 1 year of treatment in patients with ATTRwt-CA. METHODS AND RESULTS: We included 23 patients (mean age, 76 years) with ATTRwt-CA confirmed via biopsy. We analysed the left ventricular and LA strain using 2D speckle-tracking echocardiography and compared these parameters before and 1 year after starting treatment with tafamidis between 16 patients with sinus rhythm (SR) and 7 patients with atrial fibrillation (AF). In ATTRwt-CA patients with SR, LA reservoir strain significantly improved by 1-year tafamidis treatment (10.5 ± 5.0% to 11.9 ± 5.3%, P = 0.0307) although global longitudinal strain (GLS) did not (-10.6 ± 3.1% to -11.3 ± 3.0%, P = 0.0608). In contrast, LA reservoir strain was not significantly changed (5.4 ± 2.9% to 4.9 ± 1.7%, P = 0.4571), and GLS deteriorated (-8.4 ± 2.3% to -6.8 ± 1.4%, P = 0.0267) in ATTRwt-CA patients with AF. CONCLUSION: LA function improved with tafamidis treatment in ATTRwt-CA patients with SR but not left ventricular function. However, these cardiac functions did not improve with tafamidis treatment in ATTRwt-CA patients with AF.

Right Ventricular Dyssynchrony in Patients With Chronic Thromboembolic Pulmonary Hypertension and Pulmonary Arterial Hypertension.

BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) and pulmonary arterial hypertension (PAH) are characterized by elevated pulmonary arterial pressure resulting in right heart failure. Right ventricular (RV) dyssynchrony may be associated with early-stage RV dysfunction; however, the differences in RV dyssynchrony between CTEPH and PAH and the factors contributing to RV dyssynchrony remain unclear.Methods and Results: Forty-four patients (CTEPH, 26; PAH, 18) were enrolled in this study. RV dyssynchrony was assessed by determining the standard deviation of the intervals from the peak QRS to peak systolic strain for 6 segments of the RV free and septal wall by using 2-dimensional speckle-tracking echocardiography (RV-6SD). The RV-6SD, pulmonary hemodynamics, echocardiographic findings, and patient demographics in CTEPH and PAH patients were compared and their correlations with RV-6SD were investigated. CTEPH patients were older and had significantly higher pulse pressure of the pulmonary artery (PP), tricuspid valve regurgitation pressure gradient, and RV-6SD, and lower pulmonary arterial compliance (PAC), despite showing comparable pulmonary arterial pressures. Age-adjusted multiple logistic analysis showed that RV-6SD and PAC were predictors of CTEPH rather than PAH. RV-SD6 was positively correlated with PP and RV dimension and negatively correlated with PAC. CONCLUSIONS: CTEPH patients showed more evident RV dyssynchrony than PAH patients. Low PAC and a widened PP may delay RV free wall motion and cause RV dyssynchrony.

Longitudinal strain of right ventricular free wall by 2-dimensional speckle-tracking echocardiography is useful for detecting pulmonary hypertension.

AIMS: Echocardiography is widely used for screening pulmonary hypertension (PH). More recently developed two-dimensional speckle-tracking echocardiography (2D-STE) can assess regional deformation of the myocardium and is useful for detecting left ventricular dysfunction. However, its usefulness to assess right ventricular (RV) dysfunction is not clear. Therefore, the aim of this study was to investigate the ability of peak systolic strain (PSS) and post-systolic strain index (PSI) at the RV free wall determined by 2D-STE to detect PH. MAIN METHODS: Thirty-six images (27 images from PH patients, nine from patients with connective tissue disease without PH) obtained by 2D-STE were analysed. We investigated the relationship between RV hemodynamics measured by right heart catheterization and PSS, PSI and other echocardiographic parameters reflecting RV overload including RV end-diastolic diameter (RVDd) and tricuspid valve regurgitant pressure gradient (TRPG). KEY FINDINGS: PSS, PSI, RVDd and TRPG were all correlated with mean pulmonary arterial pressure (MPAP) and pulmonary vascular resistance (PVR). Furthermore, when PSS and MPAP were measured twice, the change in PSS was correlated with the change in MPAP (r=0.633, p=0.037). Multivariate logistic regression analysis identified PSS as the only independent factor associated with MPAP ≥ 35mmHg [odds ratio (OR), 1.616; 95% confidence interval (CI) 1.017-2.567; p=0.042] and PVR ≥ 400dyn·s·cm(-5) (OR, 1.804; 95% CI 1.131-2.877; p=0.013). Furthermore, the optimal PSS cut-off value to detect an elevated MPAP and PVR was -20.75%, based on receiver operating characteristic curve analysis. SIGNIFICANCE: PSS of the RV free wall might serve as a useful non-invasive indicator of PH.