The purpose of this study was to examine the relationship between long-term efficacy of amiodarone therapy (100-200 mg/day) combined with angiotensin converting enzyme inhibitor (ACEI; enalapril 5 mg/day) administration, and the development of structural atrial remodeling in patients with paroxysmal atrial fibrillation (AF). Fifty-eight patients (40 men, 18 women, mean age, 68 ± 8 years, mean follow-up period, 43 ± 18 months) with AF refractory to ≥ two class I antiarrhythmic drugs were divided into two groups; those treated with enalapril on amiodarone (group A, n = 25) and those treated with amiodarone alone (group B, n = 33), to evaluate the efficacy of combination therapy.
1) At 12 and 24 months, the survival rates for patients free from AF recurrence were 80% and 64% in group A, and 45% and 30% in group B, respectively (P < 0.05, group A versus group B). The percentage of patients with conversion to permanent AF despite amiodarone therapy was 20% in group A and 48.5% in group B (P < 0.05, group A versus group B). 2) In group B, left atrial dimension (LAD) was significantly greater after amiodarone therapy (40.2 ± 6.3 mm) than at baseline (35.2 ± 6.6 mm) (P < 0.01), whereas there was no significant difference in LAD between baseline and after amiodarone therapy in group A (39.1 ± 5.0 mm versus 41.0 ± 5.0 mm, respectively).
In patients with paroxysmal AF, ACE-I appears to enhance the efficacy of amiodarone therapy in maintaining sinus rhythm and preventing the development of structural remodeling in atria.