Improvement in left atrial strain after percutaneous mitral valvuloplasty is an independent prognostic marker in patients with rheumatic mitral stenosis.

BACKGROUND: Rheumatic mitral stenosis (MS) leads to left atrial (LA) pressure overload, resulting in progressive atrial remodeling and dysfunction. Percutaneous mitral valvuloplasty (PMV) relieves LA pressure overload and is the primary treatment for severe MS. LA reservoir strain (LASr), assessed by speckle-tracking echocardiography, allows early detection of LA dysfunction, which may improve immediately after the procedure, with potential prognostic implications. In this study, we analyzed the prognostic value of post-procedural improvement in LASr beyond well-established predictors.

METHODS: Patients with rheumatic MS undergoing PMV were prospectively recruited. All patients underwent a transthoracic echocardiogram before and within 48 h after the procedure. The primary outcome was a composite of cardiac death or need for mitral valve replacement (MVR). The prognostic value of the change in LASr post and pre PMV (ΔLASr) was assessed using a Cox proportional hazards model adjusted for known prognostic factors.

RESULTS: In total, 163 patients were included. Overall, patients were aged 46 (IQR 37-54) years, 82.8% were female, median mitral valve area pre PMV was 0.97 (IQR 0.82-1.13) cm2 and median ΔLASr was +3.2 (IQR -0.4 to +6.2). Over a median follow-up of 55 months (IQR 27-83), 46 patients had the composite outcome (28%), being 9 cardiac deaths and 37 MVR. In the final Cox model, ΔLASr was an independent predictor of the composite outcome [HR: 0.93 (0.87-0.99), p = 0.021].

CONCLUSION: Improvement in LASr independently predicted clinical outcomes in patients with rheumatic MS undergoing PMV, with each unit increase in ΔLASr associated with a 7% risk reduction of death or MVR. Assessment of LASr may be a valuable tool for post-procedural risk stratification in this population.