Impact of mitral valve treatment choice on mortality, according to etiology.

Aims: Treatment strategies of high-risk patients with mitral regurgitation (MR) differ between disease based on functional and disease based on degenerative origin. In the present study, we aimed to evaluate the effect of surgical, percutaneous, or conservative treatment of MR according to MV mechanism, for high-risk patients. Methods and results: Survival outcomes of MitraClip, surgical, or conservative strategies were compared for 688 high-risk patients with functional MR and 275 with degenerative MR. Cox regression and propensity analyses were used to correct for differences in baseline characteristics. For functional MR, conservative treatment proved to have a higher mortality hazard when compared to MitraClip treatment (hazard ratio [HR] 1.79, 95% confidence interval [CI]: 1.34 to 2.39, p<0.001), while there was no significant difference in mortality hazard between MitraClip and surgery (HR 0.86, 95% CI: 0.54 to 1.38, p=0.541). For degenerative MR, no clear significant benefit was found when comparing MitraClip to conservative and surgical treatment. Conclusions: High-risk patients with symptomatic functional MR have reduced mortality when undergoing MitraClip intervention, compared to those receiving conservative treatment.