Background: Beta-blocker therapy has been reported to improve survival and left ventricular ejection fraction (LVEF) in the setting of congestive heart failure (CHF). The magnitude and predictors of improved LVEF are unclear.
Methods: A total of 295 patients were enrolled in the study. Inclusion criteria were LVEF <35% at baseline and symptomatic (New York Heart Association class II to IV) CHF despite treatment with at minimum an angiotensin-converting enzyme inhibitor. Carvedilol was initiated at 3.125 mg twice daily and titrated to a target dose of 25 or 50 mg twice daily, depending on the patient's weight. Paired pretreatment baseline and 9 months with treatment follow-up quantitative LVEFs (assessed by resting radionuclide ventriculograms) were obtained in 161 (55 %) of the patients.
Results: LVEF improved from 25% +/- 6% at baseline to 36%+/-12% at follow-up (P<.001). Mean change in LVEF (deltaLVEF) was greater for nonischemic cardiomyopathy (NICM) (+14.5+/-2 LVEF points) than ischemic cardiomyopathy (deltaLVEF +/- 7.6+/-10 EF points, P = .001). The deltaLVEF was > or =21 LVEF points in 30% of the NICM group versus 10% of the ischemic cardiomyopathy group. Conversely, the deltaLVEF was unchanged to minimally improved (< or =5 LVEF points) in 21% of the NICM group versus 52% of the ischemic cardiomyopathy group. Multivariable analysis identified NICM and recent onset of congestive heart failure as correlates of improved LVEF.
Conclusions: Carvedilol significantly improved LVEF, especially in patients with NICM and those with recent onset of CHF.