Amiodarone has been used in Japan for

Amiodarone has been used in Japan for more than 5 years now since its approval in July 2007, and intravenous amiodarone has been widely used for life-threatening ventricular tachycardia in the setting of critical care medicine. However, only few reports have been published in the international literature about the effects of amiodarone in a Japanese population. The purpose of this paper was to review the literature concerning the K+ channel blockers amiodarone and nifekalant and to discuss the effects of both drugs and the most appropriate mode of administration.
Material and methods
Results
Discussion In study 1, which compared the effectiveness of amiodarone and nifekalant in 310 patients, both agents appeared to be almost equal in terms of prophylactic effect against ES and defibrillation effect in CPR. Hypotension and bradycardia were observed as adverse effects in the amiodarone group, and torsades de pointes was the adverse effect observed in the nifekalant group. In study 2, which compared the effectiveness of amiodarone doses in 187 patients, the ROSC success and discharge survival rates were higher in the 125-mg slow i.v. group than in the 300-mg tropisetron group. One report [21] suggested that PEA and asystole were more likely to occur in the high-dose amiodarone group.
Conflict of interest
Introduction Atrial fibrillation (AF) is one of the most common arrhythmia types in patients with heart failure (HF) [1–4]. Although AF was historically thought to deteriorate HF by various mechanisms including loss of atrial contraction, tachycardia, and irregular ventricular filling time, recent studies have demonstrated that the presence of AF was not associated with long-term mortality in patients with HF [4–6]. However, the enrolled patients in these studies were commonly those with severe HF and reduced left ventricular function requiring hospitalization. Hence, the impact of AF on unselected outpatients with HF remains unclear. Moreover, the prognostic significance of preexisting AF and later development of AF in patients with HF was thought to differ. The Framingham study showed that preexisting AF was not associated with adverse survival in patients with HF [7]. However, the prognostic significance of AF coexisting with HF in outpatients in Japanese clinical practice is not fully understood. Therefore, in the present study, we aimed to clarify the impact of AF on long-term clinical outcomes in unselected outpatients with HF by using a hospital-based cohort from The Shinken Database [8].
Material and methods
Results
Discussion AF is a common arrhythmia type in patients with HF, and its prevalence in patients with HF has been reported to be 10–50% [1–4], varying according to HF severity and the background characteristics of the study patients. In the present study, AF was seen in 15% of outpatients with HF visiting a cardiovascular hospital in Japan. This prevalence is in agreement with those of previous studies that included outpatients with HF [1,18,19]. In the present study, after adjustment for covariates, outpatients with HF and AF had a comparable risk of all-cause death to those without AF. Studies have reported that AF is an independent predictor of all-cause mortality in patients with HF [20]. However, because of changes in therapeutic trends, such as the avoidance of class I AADs and the administration of RAS-Is, the clinical outcomes of patients with HF and AF have improved dramatically [21]. Results from the Japanese Cardiac Registry of Heart Failure in Cardiology (JCARE-CARD) [5], including hospitalized patients with HF, also demonstrated that the presence of AF in HF patients was not associated with higher mortality, a finding that was in agreement with those of the present study. However, although AF was not associated with HF-related readmission after hospital discharge in JCARE-CARD, Procentriole was significantly associated with the long-term incidence of HF admission in our outpatients with HF even after adjustment for covariates.