Prognostic Implications of Increased Right Ventricular Wall Tension in Secondary Tricuspid Regurgitation
Federico Fortuni, Marlieke F. Dietz, Steele C. Butcher, Edgard A. Prihadi, Pieter van der Bijl, Nina Ajmone Marsan, Victoria Delgado, Jeroen J. Bax
Abstract
Secondary tricuspid regurgitation (TR) imposes a chronic volume overload on the right ventricle (RV) which can increase RV wall tension (RVWT). The aim of this study was to investigate the prognostic implications of increased RVWT in patients with significant secondary TR. A total of 1,142 patients with moderate-to-severe secondary TR were included. Based on the simplified Laplace-Young's law, RVWT was defined as the product between pulmonary artery systolic pressure (PASP) and RV base-to-apex length. The association between RVWT and risk of all-cause death was identified with spline curve analysis and patients were divided according to the cut-off of RVWT beyond which the hazard ratio (HR) and 95% confidence interval for all-cause mortality were above 1. Four hundred sixty-five (41%) patients had RVWT >3,300 mm Hg x mm and formed the group with increased RVWT. Patients with increased RVWT were more likely male, had more frequent heart failure symptoms and presented with more co-morbidities, larger RV and left ventricular (LV) dimensions, worse LV function, more severe secondary TR and higher PASP compared with patients with nonincreased RVWT. During a median follow-up of 51 (17 to 86) months, 586 (51%) patients died. The cumulative 5-year survival rate was significantly worse in patients with increased RVWT as compared with patients with nonincreased RVWT (38% vs 63% p <0.001). After correcting for potential confounders, increased RVWT retained an independent association with all-cause mortality (HR 1.555; 95% CI 1.268 to 1.907; p <0.001). In conclusion, increased RVWT is independently associated with worse prognosis and its evaluation may improve risk stratification in patients with significant secondary TR.