Predictive power of systolic function and congestive heart failure in patients with patients admitted for chest pain without ST elevation in the troponin era.

Background: Impaired systolic function and congestive heart failure (CHF) are powerful predictors of adverse outcomes in patients with myocardial infarction (MI). However, there are little data in which both of these variables were assessed in heterogenous patients admitted from the emergency department for exclusion of ischemia.
Methods: Consecutive patients admitted for MI exclusion who had ejection fraction (EF) measured were included. Systolic dysfunction was defined as EF <40%. Congestive heart failure was diagnosed based on clinical or x-ray evidence in the first 24 hours. Multivariate analysis was used to determine predictors of 30-day and 1-year mortality.
Results: Of the 4,343 consecutive patients admitted, 3,682 (85%) had EF assessed (including 97% of the troponin I [TnI]-positive patients) and were included. One-year unadjusted mortality was 9.5%, but in the presence of systolic dysfunction or CHF, it increased to 22% and 26%, respectively. The most important multivariate predictors of 30-day and 1-year mortality were similar and included CHF (OR for 1-year mortality 2.5, 95% CI 1.9-3.4), TnI elevations (OR 2.0, 95% CI 1.5-2.6), and severe renal failure (OR 5.2, 95% CI 3.7-7.2). Systolic dysfunction was predictive of 1 year (OR 1.9, 95% CI 1.4-2.5) but not 30-day mortality. Results were similar in the 3,018 patients who were troponin-negative.
Conclusions: Congestive heart failure is an independent predictor of both short- and long-term mortality in patients admitted for MI exclusion. In contrast, systolic dysfunction predicts long-term but not short-term mortality. One cannot be used as a surrogate for the other.