Tricuspid regurgitation in pulmonary arterial hypertension

Tricuspid regurgitation (TR) develops in PAH as a result of increased afterload and RV dilatation. TR severity correlates with haemodynamic load and is associated with poor prognosis. Volume and pressure overload reduction by diuretics and PAH-targeted drugs is the mainstay of treatment. Although no clinical trials have been performed, surgical intervention for TR is considered to be contraindicated in PAH because of an expected high morbidity and mortality. Recent clinical trials of transcatheter tricuspid valve repair (TTVR) and valve replacement using minimally invasive approaches in patients with isolated TR showed an overall benefit, despite the fact that some of the patients included in those trials had mildly elevated PAP. It is conceivable that TTVR may benefit some highly selected PAH patients, who have been responsive to PAH-targeted drugs and have preserved residual RV function. Further investigations are required to unveil this issue.