Abstract 19359: A Novel Parameter to Predict Long-term Cardiac Mortality in Mitral Stenosis

Abstract

The prognosis of patients with mitral stenosis (MS) depends on the severity of obstruction and hemodynamic burden affecting the pulmonary vasculature. Net atrioventricular compliance (C n ) reflects the overall adverse hemodynamic consequence of MS and may be useful in predicting mortality. Methods: A total of 402 MS patients (mean age 51 ± 16 years, valve area of 1.04 ± 0.24 cm 2 , 84% female) undergoing percutaneous mitral valvuloplasty (PMV) between 2000 and 2013 at 2 centers were enrolled. Invasive hemodynamic and echocardiographic measures (pre and 24 hours post PMV) were examined and patients were followed for a median of 28 months post PMV. Endpoints were cardiovascular death (primary), and a composite of death from any cause, mitral valve replacement (MVR) or repeat PMV (secondary). Results: At baseline, 138 (34%) were in atrial fibrillation and 48% were NYHA functional class III or IV. PMV resulted in significant increase in valve area, decrease in transmitral pressure gradients, pulmonary pressures and an improvement in right ventricular (RV) function. A total of 47 (12%) died (39 cardiovascular deaths). In addition, 48 patients underwent MVR, and 12 required repeat PMV with an overall incidence of adverse events of 11.4 events per 100 patient-years. Baseline C n was a strong predictor of both cardiac death (adjusted hazard ratio [HR] 0.69, 95% confidence interval [CI] 0.49 - 0.86, p = 0.008), and composite endpoint (adjusted HR 0.81, 95% CI 0.67 - 0.91, p = 0.016). Cardiac mortality was significantly higher in patients with C n ≤ 4 ml/mmHg than in patients with C n > 4 ml/mmHg (adjusted HR 0.35, 95% CI 0.16 - 0.75, p=0.007), after adjusting for clinical factors, pulmonary artery pressure, tricuspid regurgitation (TR) severity, RV function and immediate procedural results. Survival rate at 1-, 3- and 5-years follow-up was 96%, 94% and 87% in patients with C n > 4 ml/mmHg compared to 89%, 79% and 75% in patients with C n ≤ 4 ml/mmHg. Conclusions: Baseline C n is a strong predictor of cardiovascular-related mortality in patients with significant MS, after adjustment for other prognostic factors including postprocedural pulmonary artery pressure. C n assessment therefore has potential value in evaluation of mortality risk in the setting of MS.