Clinical outcome of patients with rheumatic tricuspid valve disease: matched cohort study

Rheumatic heart disease (RHD) is still a major health problem, especially in low- to mid-income countries, leading premature deaths owing to valvular disease. Although left-sided valvular involvement is most commonly seen in RHD, the tricuspid valve can also be affected. However, there is a lack of information about the prognostic value of primary tricuspid valve (TV) disease in RHD. This study aimed to determine the impact of TV disease on clinical outcome in RHD. This prospective study enrolled patients with rheumatic mitral valve disease (MVD) referred to a tertiary center for management of heart valve disease. Primary rheumatic TV disease was defined by echocardiographic features including thickening of leaflets associated with some degree of restricted mobility. Patients with rheumatic TV disease were matched to patients with MVD using 1:1 genetic matching algorithm that maximized balance of baseline covariates prior to exploring outcome differences. The main outcome was either need for MV replacement or death. Among 694 patients eligible for the study, age of 47 ± 13 years, 84% female, 39 patients (5.6%) had rheumatic TV disease. After excluding patients with incomplete data, 33 patients with TV disease were matched to 33 controls based on age, right-sided heart failure, atrial fibrillation, and MV area. During a mean follow-up of 42 months (median 28, IQR 8 to 71 months), 32 patients (48.5%) experienced adverse events, including 6 cardiovascular deaths and 26 patients who underwent surgery for mitral valve replacement. The adjusted analysis demonstrated a significant association between TV disease and the outcome, with a hazard ratio (HR) of 3.386 (95% CI 1.559-7.353; P = 0.002) in the genetic matched cohort with balance on baseline covariates of interest. The model exhibited good discriminative ability, as indicated by a C-statistic of 0.837. In patients with rheumatic mitral valve disease, rheumatic TV disease significantly increased risk of adverse events compared with matched controls. The involvement of TV may express overall disease severity that adversely affects clinical outcome.