Additional diagnostic value of right ventricular parameters in Transthyretin cardiac amyloidosis

Abstract

Transthyretin cardiac amyloidosis (ATTR) is an increasingly recognized cause of heart failure which remains a challenging diagnosis even with the advanced of multimodal imaging. Most of the studies focused on left ventricular function and remodelling. We hypothesized that right ventricle could be of addictive value to discriminate patients with confirmed ATTR. We included 299 patients with suspected ATTR evaluated by clinical examination and echocardiography. Diagnostic performances of conventional morphological and functional echocardiographic parameters were analysed. ATTR patients ( n = 109, mean age 80y ± 9, 72% male) had greater LV mass with more severe concentric remodelling as compared to controls (n = 190, mean age 71y ± 16, 51% male). LV global longitudinal strain was lower in ATTR (10.9 ± 3.7 vs. 14.5 ±4.5%; P < 0.001). Relative apical longitudinal sparing (RALS) (1.57 ± 1.6 vs. 0.86 ± 0.4; P < 0.001, AUC 0.76) and Ejection Fraction/Longitudinal strain ratio (EFSR) (4.59 ± 1.4 vs. 3.94 ± 1.1; P < 0.001; AUC 0.66) were also significantly different. When focusing on right heart parameters, ATTR patients had larger RV wall thickness (7.2 ± 1.9 vs. 4.9 ± 1.4 cm; P < 0.001); depressed systolic function: TAPSE (16.1 ± 5.6 vs. 20.9 ± 5.4 mm; P< 0.001), S’ tricuspid (10.6 ± 4.1 vs. 12.4 ± 3.2 cm/s; P < 0.001). RV free wall LS was lower in ATTR (16.9 ± 5.7 vs. 20.6 ± 6.6%; P < 0.001). RV hypertrophy showed the best diagnostic performance among RV parameters to discriminate ATTR patients (AUC 0.86). Right atrium area (AUC 0.73) and TAPSE (AUC 0.70) were also discriminant ( Fig. 1 ). Right ventricular parameters have their own place and interest in the diagnostic algorithm of ATTR especially when usual left ventricular deformation pattern have lower diagnostic performance in non-selected population. RV and RA remodelling together with parameters of RV function had interesting diagnostic performance for the ATTR diagnosis.