Clinical and prognostic role of tricuspid regurgitation in incident patients with pulmonary arterial hypertension

Aim: The clinical and prognostic role of tricuspid regurgitation (TR) in patients with pulmonary arterial hypertension (PAH) is still underappreciated. The main objective of the present study was to assess the prognostic value of TR in incident PAH patients. Methods: Consecutive incident PAH patients were enrolled from 2011 to 2021. Patients underwent right heart catheterisation (RHC), cardiopulmonary exercise test (CPET), echocardiography including the degree of TR, tricuspid annular plane systolic excursion (TAPSE), ratio of TAPSE to systolic pulmonary artery pressure (sPAP), right ventricular (RV) areas and right atrial area. The primary end-point of survival analysis was all-cause death. Results: Compared with patients with mild TR or no TR, those with TR of moderate degree or more had a worse TAPSE and TAPSE/sPAP, similar RV areas at echocardiography, worse peak oxygen consumption at CPET, and higher right atrial pressure and pulmonary vascular resistance at RHC. TR of a moderate degree or more was the only echocardiographic parameter associated with poor survival on Cox regression analyses (hazard ratio 3.34, 95% CI 1.73-6.45; p<0.001). The assessment of TR severity was crucial to determine the prognosis of patients who would have been categorised as low risk based on normal values of TAPSE or TAPSE/sPAP values. Conclusion: In treatment-naive PAH patients, TR is an important echocardiographic prognostic indicator. In particular, as an emerging concept, assessment of severity of TR is critical to stratify the prognosis of patients who would have been considered at low risk based on normal values of TAPSE or of TAPSE/sPAP.