Three year mortality in heart failure patients with very low left ventricular ejection fractions.

Background: Left ventricular ejection fraction is a predictor of the outcome in patients with chronic heart failure. Some treatments cause a small increase in ejection fraction and may, thereby, improve prognosis.
Method: We studied 99 patients with heart failure and very low left ventricular ejection fractions (all < or =20%). Seventy-four patients had ejection fractions of 11-20% and 25 had < or =10%. Patient follow up was censored at three years.
Results: Mortality was 74% at three years. Left ventricular ejection fraction was not a predictor of mortality (P = 0.36). In contrast, peak VO2 at the beginning of the study was a strong predictor of outcome (P = 0.002).
Conclusion: Three year survival is low when ejection fraction is very low. However, once the ejection fraction is < or =20% ejection fraction is no longer a predictor of mortality. These results suggest that it is unlikely that small increases in ejection fraction will be associated with a survival benefit in this group, and treatments aimed at increasing peak VO2 may be more appropriate.