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A randomized trial was conducted to assess the efficacy of amiodarone versus metropolol or no antiarrhythmic treatment to suppress asymptomatic ectopic activity and improve survival in patients who have had myocardial infarction with a left ventricular ejection fraction of 20 to 45% and ≥3 ventricular premature complexes per hour (pairs or runs). Patients (n = 368) were randomly assigned to receive amiodarone 200 mg/day (n = 115) 10 to 60 days after the acute episode, and metoprolol 100 to 200 mg/day (n = 130) or no antiarrhythmic therapy (n = 123). After a median follow-up of 2.8 years, mortality in the amiodarone-treated patients (3.5 ± 2% SEM) did not differ significantly from that of untreated control subjects (7.7 ± 2.5%, p = 0.19), but was lower than that in the metoprolol group (15.4 ± 3.5%, p = 0.006). Patients treated with metoprolol had twice the mortality seen in control subjects, even though the differences were not statistically significant. Hotter studies performed at 1, 6 and 12 months showed that both amiodarone and metoprolol were equally effective in reducing heart rate, whereas only amiodarone significantly reduced ectopic activity (p

The population of patients with heart failure (HF) and mild to moderate left ventricular (LV) dysfunction is growing, and mortality remains high. There is a need for better risk stratification of patients who might benefit from primary prevention of mortality. This study aimed to evaluate the prognostic value of Holter-based parameters for predicting mortality in patients with HF with LV ejection fraction (EF) >35%. The study involved 294 patients (199 men, mean age 66 years) with HF of ischemic and nonischemic causes, New York Heart Association classes II to III, and LVEF >35%. Surface electrocardiogram and 24-hour Holter monitoring were performed at enrollment to assess traditional electrocardiographic variables, as well as heart rate variability, heart rate turbulence, and repolarization dynamics (QT/RR). Total mortality and sudden death were the primary and secondary end points. During a median 44-month follow-up, there were 43 deaths (15%). None of the traditional electrocardiographic risk parameters significantly predicted mortality. A standard deviation of all normal-to-normal RR intervals ≤86 ms, turbulence slope ≤2.5 ms/RR, and QT end/RR >0.21 at daytime were found to be independent risk predictors of mortality in multivariate analyses. The predictive score based on these 3 variables showed that patients with ≥2 abnormal risk markers were at risk of death (30% 3-year mortality rate) and sudden death (12%), similar to death rates observed in patients with LVEF ≤35%. In conclusion, increased risk of mortality and sudden death could be predicted in patients with HF with LVEF >35% by evaluating the combination of standard deviation of all normal-to-normal RR intervals, turbulence slope, and QT/RR, parameters reflecting autonomic control of the heart, baroreflex sensitivity, and repolarization dynamics.

A randomized trial was conducted to assess the efficacy of amiodarone versus metoprolol or no antiarrhythmic treatment to suppress asymptomatic ectopic activity and improve survival in patients who have had myocardial infarction with a left ventricular ejection fraction of 20 to 45% andor = 3 ventricular premature complexes per hour (pairs or runs). Patients (n = 368) were randomly assigned to receive amiodarone 200 mg/day (n = 115) 10 to 60 days after the acute episode, and metoprolol 100 to 200 mg/day (n = 130) or no antiarrhythmic therapy (n = 123). After a median follow-up of 2.8 years, mortality in the amiodarone-treated patients (3.5 +/- 2% SEM) did not differ significantly from that of untreated control subjects (7.7 +/- 2.5%, p = 0.19), but was lower than that in the metoprolol group (15.4 +/- 3.5%, p = 0.006). Patients treated with metoprolol had twice the mortality seen in control subjects, even though the differences were not statistically significant. Holter studies performed at 1, 6 and 12 months showed that both amiodarone and metoprolol were equally effective in reducing heart rate, whereas only amiodarone significantly reduced ectopic activity (p0.0001). Thus, long-term treatment with amiodarone was clearly safe in patients with an ejection fraction of 20 to 45%, was effective in suppressing arrhythmias, and was associated with a lower mortality than metoprolol; corroboration is required in a larger trial.