Amiodarone is a highly effective treatment for supraventricular and ventricular tachyarrhythmia; however, it could be associated with several serious adverse effects, including liver injury. We report the clinical and histological features of two contrasting Japanese patients with amiodarone-induced reversible and irreversible hepatotoxicity. One patient with amiodarone-induced irreversible hepatotoxicity showed liver cirrhosis during treatment with amiodarone and died of hepatic failure; the other patient, who had reversible hepatotoxicity, showed a reversible course of liver function and imaging after discontinuation of amiodarone. We emphasize the importance of close monitoring of liver enzymes and evaluation of liver computed tomographic imaging as well as liver biopsy during treatment with amiodarone, and discontinuation should be considered when amiodarone-induced hepatotoxicity is suspected.

This study explores the association between lifestyle behavior and incident atrial fibrillation (AF) in the general Japanese population. Japanese residents aged ≥40 years undergoing a national health checkup in Kanazawa City were included. We hypothesized that better lifestyle behavior is associated with lower incidence of AF. Lifestyle behavior was evaluated by the total cardiovascular health (CVH) score (0 = poor to 14 = ideal), calculated as the sum of the individual scores on seven modifiable risk factors: smoking status, physical activity, obesity, patterns of eating schedule, blood pressure, total cholesterol, and blood glucose. The association between CVH and incident AF was assessed, adjusting for other factors. A total of 37,523 participants (mean age 72.3 ± 9.6 years, 36.8% men, and mean total CVH score 9 ± 1) were analyzed. During the median follow-up period of 5 years, 703 cases of incident AF were observed. Using a low CVH score as a reference, the upper group (ideal CVH group) had a significantly lower risk of incident AF (hazard ratio [HR] = 0.79, 95% confidence interval 0.65–0.96, p = 0.02), especially among those aged <75 years (HR = 0.68, 95% confidence interval 0.49–0.94, p = 0.02). Thus, ideal CVH is independently associated with a lower risk for incident AF, particularly in younger Japanese individuals (<75 years).

Pulmonary vein isolation (PVI) is an established treatment for atrial fibrillation (AF). While it is known to affect the autonomic nervous system, the relationship between left atrial (LA) remodeling and PVI-mediated neuromodulation remains unclear. We aimed to assess the neuromodulatory effects of PVI using skin sympathetic nerve activity (SKNA). SKNA was recorded one day before and 2–3 days after PVI in 28 paroxysmal AF (PAF) and 33 persistent AF (PerAF) groups. Baseline low frequency to high frequency (LF/HF) ratio was higher in the PAF group (1.23 [interquartile range {IQR}: 0.79–1.76] vs. 0.74 [IQR: 0.49–1.38], p = 0.017). After PVI, the PAF group demonstrated significant reductions in burst amplitude (1.46 [IQR: 1.04–2.84] vs. 1.09 [IQR: 0.78–2.17] μV, p = 0.015) and LF/HF ratio (0.91 [IQR: 0.73–1.52] vs. 0.71 [IQR: 0.48–1.21], p = 0.012), whereas the PerAF group exhibited no such changes. A weak positive correlation was observed between the percentage change in LF/HF ratio and LA volume index in the PAF group (r = 0.572, p = 0.002). PVI significantly decreased SKNA in PAF patients but not in PerAF. LA remodeling may hinder the effectiveness of PVI-mediated neuromodulation.