Authors
Packer M, Coats AJS, Fowler MB, et al.
Title
Effect of Carvedilol on Survival in Severe Chronic Heart Failure
References
N Engl J Med 2001;344:1651-8.
Background
At the time of initiation of this study, beta-blockers improve survival and decrease hospitalization rates in patients with mild-to-moderate heart failure. Their role in patients with severe HF was not established.
Purpose
To determine whether carvedilol, when added to conventional therapy, positively affects survival rates in patients with severe chronic heart failure (symptomatic at rest or minimal exertion and LVEF <25%).
Design
  • Randomized, double-blind, placebo-controlled trial
  • 2289 patients with severe but stable chronic HF (defined as dyspnea or fatigue at rest or on minimal exertion and LVEF <25%) due to ischemic or non-ischemic cardiomyopathy
  • Receiving conventional therapy: diuretic and ACEi (or ARB); permitted to use digoxin, nitrates, hydralazine, spironolactone and amiodarone if needed
  • Hospitalized patients could be enrolled if without intensive care or continued inpatient care requirements
Exclusion Criteria
  • Contraindications to β-blockers; IV inotropes or vasodilators use within 4 days of screening; use of alpha-blocker, calcium channel blocker, or class I antiarrhythmic drugs in the past 4 weeks or beta-blocker use in the past 2 months
  • previous or planned heart transplant; HF due to reversible cardiomyopathy, primary valvular disease; severe primary pulmonary, renal or hepatic disease
  • within the last two months: coronary revascularization, MI, CVA, sustained or hemodynamically unstable VT or VF
  • SBP <85 mmHg, HR <68 bpm, serum creatinine >247.5 µmol/L, potassium <3.5 or >5.2 mmol/L; >44.2 µmol/L SCr or >1.5 kg increases during screening period
Follow-Up
Mean 10.4 months (stopped early, due to survival benefits of carvedilol)
Treatment Regimen
  • Carvedilol 3.125 mg twice daily (if tolerated, dose increased every two weeks to 6.25 mg, then 12.5 mg and target of 25 mg twice daily) vs. placebo
Results

Primary Endpoint

Death:

  • Cumulative risk at 1 year - 18.5% (placebo) vs. 11.4% (carvedilol)
  • Risk decreased by 35% with carvedilol vs. placebo, p=0.00013 (unadjusted) and p=0.0014 (after adjustment for interim analyses)


Secondary Endpoint

Combined death or hospitalization: 24% decrease with carvedilol vs. placebo, p <0.001


Subgroup analyses: in the very high risk group of patients with recent or recurrent cardiac decompensation or severely depressed cardiac function, cumulative risk of death at one year was 24%; carvedilol reduced this risk by 39% (p=0.009) and decreased combined death or hospitalization by 29% (p=0.003)

Safety: discontinuation of treatment due to adverse effects were higher in the placebo group than with carvedilol (p=0.02).

Summary
In patients with severe chronic heart failure despite diuretic + ACEi (or ARB) therapy, carvedilol significantly increases survival, decreases hospitalizations and is well tolerated as compared to placebo.