Prognostic Implications of Right Ventricular Systolic Dysfunction in Cardiac Amyloidosis

Abstract

Left ventricular (LV) systolic dysfunction in cardiac amyloidosis (CA) is associated with poor prognosis. This study aimed to investigate the prognostic implications of right ventricular (RV) systolic dysfunction in CA. A total of 93 patients diagnosed with CA who underwent standard and speckle-tracking echocardiography were included. During a median follow-up of 17 (5 to 38) months, 42 patients (45%) died. Nonsurvivors were more likely to present with immunoglobulin light-chain amyloidosis and New York Heart Association class III to IV heart failure symptoms. Regarding the echocardiographic characteristics, nonsurvivors had a higher LV apical ratio, worse LV diastolic function, and worse RV systolic function (evaluated with both tricuspid annular plane systolic excursion and RV free wall strain). RV free wall strain was independently associated with all-cause mortality in several multivariable Cox regression models and had incremental prognostic value over conventional parameters of RV function when added to a basal model (including heart failure symptoms, amyloidosis phenotype, and LV global longitudinal strain). Based on spline curve analysis and Youden index, a value of 16% for RV free wall strain was identified as the optimal cutoff to predict outcome and patients with RV free wall strain <16% had a significantly worse short- and long-term survival during follow-up (1- and 3-year cumulative survival: 81% vs 31% and 67% vs 20%, respectively, p <0.001). In conclusion, RV systolic dysfunction is independently associated with poor outcome in patients with CA and the use of advanced echocardiographic parameters, such as RV free wall strain, may be of aid for better risk stratification.