Early percutaneous mitral commissurotomy or conventional management for asymptomatic mitral stenosis: a randomised clinical trial.

OBJECTIVE: The decision to perform percutaneous mitral commissurotomy (PMC) on asymptomatic patients requires careful weighing of the potential benefits against the risks of PMC, and we conducted a multicentre, randomised trial to compare long-term outcomes of early PMC and conventional treatment in asymptomatic, severe mitral stenosis (MS).

METHODS: We randomly assigned asymptomatic patients with severe MS (defined as mitral valve area between 1.0 and 1.5 cm2) to early PMC (84 patients) or to conventional treatment (83 patients). The primary endpoint was a composite of major cardiovascular events, including PMC-related complications, cardiovascular mortality, cerebral infarction and systemic thromboembolic events. The secondary endpoints were death from any cause and mitral valve (MV) replacement during follow-up.

RESULTS: In the early PMC group, there were no PMC-related complications. During the median follow-up of 6.4 years, the composite primary endpoint occurred in seven patients in the early PMC group (8.3%) and in nine patients in the conventional treatment group (10.8%) (HR 0.77; 95% CI 0.29 to 2.07; p=0.61). Death from any cause occurred in four patients in the early PMC group (4.8%) and three patients in the conventional treatment group (3.6%) (HR 1.30; 95% CI 0.29 to 5.77). Ten patients (11.9%) in the early PMC group and 17 patients (20.5%) in the conventional treatment group underwent MV replacement (HR 0.59; 95% CI 0.27 to 1.29).

CONCLUSIONS: Compared with conventional treatment, early PMC did not significantly reduce the incidence of cardiovascular events among asymptomatic patients with severe MS during the median follow-up of 6 years.

TRIAL REGISTRATION NUMBER: NCT01406353.