Procedural success and outcomes after percutaneous balloon mitral valvuloplasty in rheumatic mitral stenosis with moderate mitral regurgitation: a retrospective cohort study

Background: Percutaneous balloon mitral valvuloplasty (PBMV) is contraindicated in mitral stenosis (MS) with moderate mitral regurgitation (MR) according to the European guidelines. However, small-sized studies have demonstrated the feasibility and safety of PBMV in these patients. We aimed to study the procedural success and mid-term outcomes of PBMV in MS patients with moderate MR.Methods: The present study was a retrospective cohort study in consecutive patients with severe rheumatic MS who underwent PBMV with the Inoue technique in Songklanagarind hospital. The severity of mitral regurgitation was assessed with qualitative Doppler. The patients were grouped according to their MR severity before PBMV into moderate MR or less-than-moderate MR. Procedural success and a composite of all-cause death, mitral valve surgery or re-PBMV were compared between the two groups.Results: Of 618 patients with rheumatic MS who underwent PBMV in Songklanagarind hospital between January 2003 and October 2020, 598 patients (96.8%) had complete information of pre-PBMV MR severity and procedural success. Forty-nine patients (8.2%) had moderate MR before PBMV. Moderate MR before PBMV was not associated with a lower chance of PBMV success (moderate MR vs. less-than-moderate MR before PBMV; adjusted OR 0.65, 95% CI: 0.32-1.29, P=0.22). Survival probability of all-cause death, MV surgery or re-PBMV in the group with moderate MR before PBMV was not different from the group with less-than-moderate MR (adjusted HR 1.30, 95% CI: 0.98-1.62, P=0.10).Conclusions: PBMV is an effective and safe treatment in rheumatic MS with moderate MR.