Outcomes of Mechanical Mitral Valve Replacement with Preservation of Posterior Leaflet in Patients with Reduced Left Ventricular Function

Background: Compromised left ventricular function presents unique challenges during mitral valve surgery. Recent evidence suggests subvalvular apparatus preservation might enhance postoperative recovery in high-risk populations. Methods: This prospective observational investigation (Hue Central Hospital, March 2015-September 2016) evaluated 87 patients undergoing mechanical mitral valve replacement with posterior leaflet preservation. Participants were stratified into two groups: reduced ejection fraction (EF ≤50%, n=38) and preserved EF (>50%, n=49). Comprehensive clinical and echocardiographic assessments were conducted at 1, 3, 6, and 12 months postoperatively. Statistical analysis employed parametric and non-parametric methodologies, with survival analyzed via Kaplan-Meier techniques. Results: The reduced EF cohort demonstrated significant improvement in contractile performance from 48.8±5.2% preoperatively to 61.6±7.2% at 12 months (p<0.05). Ventricular dimensions decreased notably from 59.2±6.6mm to 47.6±4.0mm (p<0.05). Hospital mortality was 2.3% (2 patients). Twelve-month survival rates reached 94.66% and 97.96% for reduced and preserved EF groups, respectively, without significant inter-group differences (p=0.42). All surviving participants achieved functional status in NYHA class I or II. Conclusion: Mechanical mitral valve replacement with posterior leaflet preservation represents an effective approach for patients with reduced ventricular performance, promoting substantial improvement in cardiac function and excellent clinical outcomes.