EFFECTS OF AMIODARONE ON THE CIRCADIAN PATTERN OF SUDDEN CARDIAC DEATH (DEPARTMENT-OF-VETERANS-AFFAIRS CONGESTIVE HEART FAILURE-SURVIVAL TRIAL OF ANTIARRHYTHMIC THERAPY)

Some antiarrhythmic drugs have been shown to influence the circadian p attern of sudden cardiac death (SCD), The effect of chronic amiodarone therapy on this pattern is unknown. This study determines the circadi an pattern of deaths in the Congestive Heart Failure-Survival Trial of Antiarrhythmic Therapy (CHF-STAT) and compares the distribution of SC D between the amiodarone and the placebo arms of the trial, CHF-STAT w as a multicenter trial that determined whether amiodarone reduces mort ality in patients with heart failure and asymptomatic ventricular arrh ythmias. The time of death was retrospectively analyzed in patients wh o died from pump failure and SCD. In patients who died suddenly, the c ircadian pattern of deaths was compared between patients receiving ami odarone and those receiving placebo. In CHF-STAT, 274 patients died du ring follow-up.The time of death was available in 65 of the 74 patient s who died from pump failure, and in 96 of the 139 patients who died s uddenly. There was a circadian variation of all SCDs compared with oth er deaths with a distinct peak during the morning (p = 0.04). A simila r morning peak of sudden cardiac death was found in both the amiodaron e (n = 42) and the placebo (n = 54) groups, and the overall circadian pattern did not differ between them (p = 0.16), in contrast, death fro m pump failure occurred equally distributed over time. Thus, SCD occur s predominantly during the morning, whereas death from heart failure d oes not exhibit a morning peak. Amiodarone does not influence the circ adian pattern of SCD. (C) 1997 by Excerpta Medico, Inc.