Impact of right ventricular dysfunction on transcatheter mitral valve implantation outcomes, and subsequent evolution of right ventricular function.

BACKGROUND: The impact of right ventricular dysfunction on transcatheter mitral valve implantation outcomes and the evolution of right ventricular function after the procedure has not been described.

AIMS: To analyse the impact of right ventricular dysfunction on immediate and mid-term outcomes of transcatheter mitral valve implantation, and the evolution of right ventricular function in these patients.

METHODS: Consecutive patients who underwent transcatheter mitral valve implantation in our institution were included. Right ventricular function was assessed before transcatheter mitral valve implantation by transthoracic echocardiography, using a multivariable approach. Patients were divided into two groups according to the preprocedural presence of right ventricular dysfunction. Patients were followed up at 3 months and 1 year with a new echocardiographic assessment at each time point.

RESULTS: Among 109 patients finally included (mean age 65±19 years; 66% women), 77 (71%) had normal right ventricular function and 32 (29%) had right ventricular dysfunction before transcatheter mitral valve implantation. Technical success was achieved in 92 (84%) patients. At 30 days, there were no differences between the group with normal right ventricular function and the group with right ventricular dysfunction in terms of death (5 vs. 6%; P=0.86), all-cause rehospitalization (20 vs. 31%; P=0.17) and heart failure without hospitalization (13 vs. 6%; P=0.5). Although the 1-year survival rate was higher in the group with normal right ventricular function (83.1%, 95% confidence interval 74.3% to 92.9%) than in the group with right ventricular dysfunction (68.2%, 95% confidence interval 52.9% to 88.1%) (P=0.09), these differences were not significant after adjustment. Transcatheter mitral valve implantation was associated with improved right ventricular function in the group with initial right ventricular dysfunction at 1-year follow-up (P<0.01).

CONCLUSIONS: Right ventricular dysfunction does not appear to have an impact on the early outcomes of transcatheter mitral valve implantation. However, it was associated with an increased rate of late death, although differences were not statistically significant after adjustment. Successful transcatheter mitral valve implantation in patients with severe mitral valve disease associated with right ventricular dysfunction leads to significant improvement in right ventricular function.