Effect of Low-Dose Amiodarone on Atrial Fibrillation or Flutter in Japanese Patients With Heart Failure.

Abstract

The efficacy and safety of amiodarone in the management of atrial fibrillation (AF) or flutter in 108 Japanese patients with heart failure was retrospectively examined. Thirty-four (41%) of the 82 patients who were in sinus rhythm after 1 month of amiodarone administration had their first recurrence, 70% of cases occurring within 1 year of initiation. The cumulative rates of maintenance of sinus rhythm were 0.68, 0.55, and 0.47 at 1, 3, and 5 years, respectively. Amiodarone was more effective in maintaining sinus rhythm in patients with paroxysmal AF or flutter than in those with the persistent form (p<0.05). The cumulative rates for cases that remained in permanent AF were 0.04, 0.11, and 0.14 at 1, 3, and 5 years, respectively. Apart from suppressing AF, the mean heart rate during Holter monitoring was significantly decreased with amiodarone therapy in cases of permanent AF. Adverse effects requiring the discontinuation of amiodarone therapy occurred in 16% of patients. Low-dose amiodarone therapy may prevent AF or flutter in Japanese patients with heart failure. (Circ J 2002; 66: 600 -604)

Long-Term Efficacy of Amiodarone Therapy for the Prevention of Recurrence of Paroxysmal Atrial Fibrillation Analysis Based on Patient Characteristics

“…37) Other studies in small numbers of Japanese patients with atrial tachycardia found that 2.7-3.6% of patients receiving amiodarone developed pulmonary toxicity during mean follow-up periods of 30-36 months. 14,38) In the present study, the incidence of pulmonary toxicity was 1.4% per year, which is not low in comparison to American and European data. 37) These findings suggested that we should reduce the incidence of amiodarone-induced pulmonary toxicity because there is no safe dose of amiodarone therapy, at least in Japanese patients.…”

Incidence and Predictors of Pulmonary Toxicity in Japanese Patients Receiving Low-Dose Amiodarone

“…Other studies in small numbers of Japanese patients with atrial tachyarrhythmia show that 2.7-3.6% of patients receiving amiodarone developed APT during mean follow-up periods of 30-36 months. 16,17 Although the backgrounds, number of subjects, or follow-up periods were different, there is a relatively high incidence of APT in Japanese patients. The reason why it should be higher than in previous reports from Europe and the United States, despite the extremely low dose of amiodarone used in Japanese patients, is unclear.…”

Patterns and Predictors of Discontinuation of Rhythm‐Control Drug Therapy in Patients with Newly Diagnosed Atrial Fibrillation

“…1 This is highlighted by the high rates of discontinuation often observed in clinical trials of rhythm-control therapies, reportedly due to adverse events and lack of efficacy. [5][6][7][8][9] A study of 481 patients with atrial fibrillation enrolled in the Fibrillation Registry Assessing Costs, Therapies, Adverse Events and Lifestyle (FRACTAL) who began to receive antiarrhythmic drugs between 1997 and 2000 demonstrated that at 1 year, the percentages of patients who had discontinued therapy were as high as 68% for class Ia antiarrhythmics (disopyramide, procainamide, quinidine), 41% for class Ic antiarrhythmics (encainide, flecainide, propafenone), 36% for sotalol, and 18% for amiodarone. 10 However, to the best of our knowledge, no large-scale studies have examined the rate and temporal patterns of discontinuation of rhythm-control therapies for atrial fibrillation in current clinical practice in the United States.…”