Mid-term (up to 12 years) clinical and echocardiographic outcomes of percutaneous transvenous mitral commissurotomy in patients with rheumatic mitral stenosis.

BACKGROUND: Rheumatic heart disease (RHD) is still a concerning issue in developing countries. Among delayed RHD presentations, rheumatic mitral valve stenosis (MS) remains a prevalent finding. Percutaneous transvenous mitral commissurotomy (PTMC) is the intervention of choice for severe mitral stenosis (MS). We aimed to assess the mid-term outcome of PTMC in patients with immediate success. METHODS: In this retrospective cohort study, out of 220 patients who had undergone successful PTMC between 2006 and 2018, the clinical course of 186 patients could be successfully followed. Cardiac-related death, undergoing a second PTMC or mitral valve replacement (MVR) were considered adverse cardiac events for the purpose of this study. In order to find significant factors related to adverse cardiac outcomes, peri-procedural data for the studied patients were collected.The patients were also contacted to find out their current clinical status and whether they had continued secondary antibiotic prophylaxis regimen or not. Those who had not suffered from the adverse cardiac events were additionally asked to undergo echocardiographic imaging, in order to assess the prevalence of mitral valve restenosis, defined as mitral valve area (MVA) < 1.5 cm2 and loss of ≥ 50% of initial area gain. RESULTS: During the mean follow-up time of 5.69 ± 3.24 years, 31 patients (16.6% of patients) had suffered from adverse cardiac events. Atrial fibrillation rhythm (p = 0.003, HR = 3.659), Wilkins echocardiographic score > 8 (p = 0.028, HR = 2.320) and higher pre-procedural systolic pulmonary arterial pressure (p = 0.021, HR = 1.031) were three independent predictors of adverse events and immediate post-PTMC mitral valve area (IMVA) ≥ 2 cm2 (p < 0.001, HR = 0.06) was the significant predictor of event-free outcome. Additionally, follow-up echocardiographic imaging detected mitral restenosis in 44 patients (23.6% of all patients). The only statistically significant protective factor against restenosis was again IMVA ≥ 2 cm2 (p = 0.001, OR = 0.240). CONCLUSION: The mid-term results of PTMC are multifactorial and may be influenced by heterogeneous peri-procedural determinants. IMVA had a great impact on the long-term success of this procedure. Continuing secondary antibiotic prophylaxis was not a protective factor against adverse cardiac events in this study. (clinicaltrial.gov registration: NCT04112108).