Outcomes of Severe Mitral Stenosis With the Revised Severity Criteria: Mitral Valve Replacement vs Percutaneous Mitral Valvuloplasty

Background: This study aimed to compare the outcomes, according to percutaneous mitral valvuloplasty (PMV) vs mitral valve replacement (MVR), of severe mitral stenosis (MS) with the updated criteria (MVA ≤ 1.5 cm²). Methods: From the Multicenter Mitral Stenosis With Rheumatic Etiology (MASTER) registry of 3140 patients, we included patients with severe MS who underwent PMV or MVR between January 2000 and December 2021 except for previous valvular surgery/intervention, at least moderate other valvular dysfunction, and thrombus at the left atrium/appendage. Moderately severe MS (MS-MS) and very severe MS (VS-MS) were defined as 1.0 cm² < MVA ≤ 1.5 cm² and MVA ≤ 1.0 cm², respectively. Primary outcomes were a composite of cardiovascular (CV) death and heart failure (HF) hospitalization. Secondary outcomes were a composite of primary outcomes and redo intervention. Results: Among 442 patients (mean 56.5 ±11.9 years, women 77.1%), the MVR group (n = 260) was older, had more comorbidities, higher echoscore, larger left chambers, and higher right ventricular systolic pressure than the PMV group (n = 182). During a mean follow-up of 6.9 ± 5.2 years with inverse probability-weighted matching, primary outcomes did not differ, but the MVR group experienced fewer secondary outcomes (P = 0.010). In subgroup analysis of patients with MS-MS and VS-MS, primary outcomes did not differ. However, the MVR group in patients with VS-MS showed better secondary outcomes (P = 0.012). Conclusions: PMV or MVR did not influence CV mortality or HF hospitalization in both MS-MS and VS-MS. However, because of increased early redo intervention in the PMV group in VS-MS, MVR would be the preferable option without clear evidence of suitable morphology for PMV.