Exercise capacity is the most powerful predictor of 2-year mortality in patients with left ventricular systolic dysfunction.

BACKGROUND: There are few data about predictors of cardiovascular mortality and rehospitalization rate in patients with left ventricular systolic dysfunction (LVSD) after myocardial revascularization and optimization of pharmacological treatment. PATIENTS AND METHODS: 1,346 consecutive patients with left ventricular ejection fraction (LVEF) < 45% (64 + or - 10 years, 73% male, LVEF 36.3% + or - 8%), who were referred for inpatient cardiac rehabilitation, were followed prospectively for 731 + or - 215 days in a unicentric prospective longitudinal registry. Multivariate logistic regression Cox models were used to analyze demographic, echocardiographic and exercise variables in order to determine independent predictors of cardiovascular mortality and rehospitalization.
RESULTS: LVEF failed to show prognostic power (hazard ratio [HR] 0.99 [95% confidence interval, CI, 0.94-1.03]; p = not significant), whereas moderate to severe mitral regurgitation (HR, 5.71 [95% CI 1.75-18.6]; p = 0.004) and atrial fibrillation (HR 1.67 [95% CI 1.15-2.44]; p = 0.008) were associated with a poorer prognosis. In an optimized multivariate model, 6-min walk test (HR 0.93 [95% CI 0.86-1.00] per 50 m; p = 0.049) and symptom-limited maximum exercise capacity test (HR 0.83 [95% CI 0.76-0.91] per 10 W; p < 0.001) as well as female gender (HR 0.58 [95% CI 0.39-0.84]; p = 0.005) were strong predictors for reduced overall mortality.
CONCLUSION: In patients with LVSD, independently of LVEF, traditional prognostic factors including atrial fibrillation or mitral regurgitation predict poorer survival, whereas symptom-limited exercise capacity and walking distance performed in 6-min walk test were highly predictive for a good prognosis.