Risk factors for recurrent tricuspid regurgitation after pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension

Objective Pulmonary thromboendarterectomy often improves tricuspid regurgitation in chronic thromboembolic pulmonary hypertension, but determinants and consequences of late recurrence remain unclear. We evaluated tricuspid regurgitation trajectories, predictors of recurrent moderate or greater regurgitation, and its association with mortality. Methods Adults undergoing pulmonary thromboendarterectomy at a comprehensive chronic thromboembolic pulmonary hypertension center between May 2016 and September 2025 were retrospectively studied. Tricuspid regurgitation severity was assessed preoperatively, at discharge, and during follow-up. Right atrial reservoir strain and right ventricular longitudinal strain were quantified using speckle-tracking echocardiography. Recurrent moderate or greater regurgitation was analyzed using competing risk methods, and mortality was assessed using Cox models with tricuspid regurgitation as a time-varying exposure. Results Among 170 patients (143 with late follow-up), 36 (25%) developed recurrent moderate or greater tricuspid regurgitation. Preoperative moderate or greater tricuspid regurgitation (hazard ratio 2.2, p=.027) and lower right atrial reservoir strain (hazard ratio 1.03; p=.017) were associated with recurrence; tricuspid annular diameter and baseline right ventricular function were not. Pre-discharge tricuspid regurgitation severity was the strongest predictor (mild: hazard ratio 3.1, p=.004; moderate–severe: hazard ratio 5.5, p<.001). Higher pre-discharge pulmonary vascular resistance was also associated with recurrence and mortality. Conclusions Recurrent tricuspid regurgitation after pulmonary thromboendarterectomy is more common than previously thought and is associated with preoperative and residual tricuspid regurgitation and persistent pulmonary hypertension, but not annular diameter. Impaired right atrial reservoir function is a novel predictor of late tricuspid valve regurgitation with implications for concomitant repair and postoperative surveillance.