Sudden death in mitral regurgitation due to flail leaflet

OBJECTIVES We sought to assess the incidence and determinants of sudden dea th (SUD) in mitral regurgitation due to flail leaflet (MR-FL). BACKGROUND Sudden death is a catastrophic complication of MR-FL. Its incide nce and predictability are undefined. METHODS The occurrence of SUD was analyzed in 348 patients (age 67 +/- 12 y ears) with MR-FL diagnosed echocardiographically from 1980 through 1994. RESULTS During a mean follow-up of 48 +/- 41 months, 99 deaths occurred und er medical treatment. Sudden death occurred in 25 patients, three of whom w ere resuscitated. The sudden death rates at five and 10 years were 8.6 +/- 2% and 18.8 +/- 4%, respectively, and the linearized rate was 1.8% per year . By multivariate analysis, the independent baseline predictors of SUD were New York Heart Association (NYHA) functional class (p = 0.006), ejection f raction (p = 0.0001) and atrial fibrillation (p = 0.059). The yearly linear ized rate of sudden death was 1% in patients in functional class I, 3.1% in class II and 7.8% in classes III and IV. However, of 25 patients who had S UD, at baseline, 10 (40%) were in functional class I, 9 (36%) were in class II and only 6 (24%) in class III or IV. In five patients (20%), no evidenc e of risk factors developed until SUD. In patients with an ejection fractio n greater than or equal to 60% and sinus rhythm, the Linearized rate of SUD was not different in functional classes I and II (0.8% per year). Surgical correction of MR (n = 186) was independently associated with a reduced inc idence of SUD (adjusted hazard ratio [95% confidence interval] 0.29 [0.11 t o 0.72], p = 0.007). CONCLUSIONS Sudden death is relatively common in patients with MR-FL who ar e conservatively managed. Patients with severe symptoms, atrial fibrillatio n and reduced systolic function are at higher risk, but notable rates of SU D have been observed without these risk factors. Correction of MR appears t o be associated with a reduced incidence of SUD, warranting early considera tion of surgical repair. (C) 1999 by the American College of Cardiology.