Pulmonary Effect of Amiodarone in Patients With Heart Failure

OBJECTIVES: The purpose of this study was to evaluate the pulmonary effects of amiodarone in patients with heart failure, in those with chronic obstructive pulmonary disease (COPD) and in those undergoing a surgical procedure. BACKGROUND: Amiodarone has been known to cause pulmonary complications; especially in those with COPD and in those undergoing a surgical procedure. METHODS: Patients receiving vasodilator therapy for congestive heart failure were prospectively randomized to placebo or amiodarone at 800 mg/day for 14 days, 400 mg/day for 50 weeks and then 300 mg/day thereafter. Chest X-ray film and pulmonary function tests with diffuse capacity of carbon monoxide (DLCO) were obtained at baseline and annually. The power to detect a 20% difference in DLCO at 1 year exceeded 90% in all patients and in those with COPD (two-sided alpha = 0.05). The sample allowed a 75% power to detect pulmonary complications (1% vs. 5%) between the two treatment groups. RESULTS: There was no difference in baseline characteristics between patients randomized to amiodarone (n = 269) or placebo (n = 250). The DLCO measurements at randomization were 18.3 +/- 6.9 and 17.7 +/- 7.6 ml/min per mm Hg for the amiodarone and placebo groups, respectively (p = 0.3). At 1 and 2 years, DLCO measurements were 17.7 +/- 7.0 and 18.3 +/- 7.7 ml/min per mm Hg for the amiodarone group and 17.9 +/- 7.2 and 18.2 +/- 7.2 for the placebo group, respectively. There were no significant differences between the groups, with corresponding p values of 0.73 ad 0.96 at years 1 and 2, respectively. Among patients with COPD, DLCO measurements at randomization were 17.9 +/- 6.7 and 15.8 +/- 6.8 ml/min per mm Hg for the amiodarone and placebo groups, respectively. At years 1 and 2, DLCO measurements were 16.6 +/- 7.8 and 17.8 +/- 9.5 ml/min per mm Hg for the amiodarone group and 16.5 +/- 6.6 and 16.3 +/- 7.0 ml/min per mm Hg for the placebo group, with corresponding p values of 0.95 and 0.48, respectively. There was no difference in survival free of noncardiac or perioperative deaths between patients assigned to amiodarone or placebo. Pulmonary fibrosis was diagnosed in four patients (1.1%) treated with amiodarone and in three patients (0.8%) receiving placebo. CONCLUSIONS: Our study shows that amiodarone can be safely used, with an acceptable pulmonary toxicity, in patients with heart failure.