Tolerability and efficacy of carvedilol in patients with New York Heart Association class IV heart failure

OBJECTIVES The purpose of this study was to assess the tolerability and eff icacy of carvedilol in patients with New York Heart Association (NYHA) func tional class IV symptoms. BACKGROUND Carvedilol, a nonselective beta-adrenergic blocking drug with al pha-adrenergic blocking and antioxidant properties, has been shown to impro ve left ventricular function and clinical outcome in patients with mild to moderate chronic heart failure. METHODS We retrospectively analyzed the outcomes of 230 patients with heart failure treated with carvedilol who were stratified according to baseline functional class: 63 patients were NYHA class IV and 167 were NYHA class I, II or III. Carvedilol was commenced at 3.125 mg b.i.d. and titrated to 25 mg b.i.d. as tolerated. Patients with class IV symptoms were older (p = 0.0 3), had lower left ventricular fractional shortening (p < 0.001), had lower six-min walk distance (p < 0.001) and were receiving more heart failure me dications at baseline compared with less symptomatic patients. RESULTS Nonfatal adverse events while taking carvedilol occurred more frequ ently in class IV patients (43% vs. 24%, p < 0.0001), and more often result ed in permanent withdrawal of the drug (25% vs. 13%, p < 0.01). Thirty-seve n (59%) patients who were NYHA class IV at baseline had improved by one or more functional class at 3 months, 8 (13%) were unchanged and 18 (29%) had deteriorated or died. Among the less symptomatic group, 62 (37%) patients h ad improved their NYHA status at 3 months, 73 (44%) were unchanged and 32 ( 1946) had deteriorated or died. The differences in symptomatic outcome at t hree months between the two groups were statistically significant (p = 0.00 1, chi-square analysis). Both groups demonstrated similar significant impro vements in left ventricular dimensions and systolic function. CONCLUSIONS Patients with chronic NYHA class IV heart failure are more like ly to develop adverse events during initiation and dose titration when comp ared with less symptomatic patients but are more likely to show symptomatic improvement in the long term. We conclude that carvedilol is a useful adju nctive therapy for patients with NYHA class IV heart failure; however, they require close observation during initiation and titration of the drug. (J Am Coil Cardiol 1999; 33:924-31) (C) 1999 by the American College of Cardio logy.