Right ventricular pulmonary vascular coupling in secondary tricuspid regurgitation: a pressure volume loop study

Abstract Introduction The severity of secondary tricuspid regurgitation (sTR) predicts outcome of patients with left heart failure with reduced ejection fraction (HFrEF). In these patients sTR predominantly occurs as a result of secondary pulmonary hypertension (PH). However, more than 46% of patients with severe PH have only mild or none sTR. In this study we tested the hypothesis that intrinsic right ventricular (RV) contractility adaptation to the pulmonary arterial (PA) vascular load (RV-PA-coupling) is associated with the presence and severity of sTR. Methods In 110 patients with HFrEF (a post-hoc analysis of the Magdeburger CRT Responder Trial, DRKS00011133) we quantified the RV intrinsic contractility response (end-systolic elastance, Ees) to pulmonary vascular afterload (arterial elastance, Ea) and its coupling ratio (RV-PA coupling ratio: Ees/Ea) by the RV pressure-volume loop catheter technique at baseline, and combined it with echocardiography-derived parameter of sTR presence and severity and RV function. Results Echocardiography at baseline demonstrated no or trace TR (TR0) in 67 patients (61%), mild TR (TR1) in 23 (21%), moderate TR (TR2) in 11 (10%), and severe TR (TR3) in 9 (8%). The transition from TR0 to TR1 was characterized by a pronounced drop of the RV-PA coupling ratio (TR0: Ees/Ea= 0.88, 0.67–1.1 vs. TR1: Ees/Ea= 0.48, 0.3–0.83, p