Angiotensin-converting enzyme inhibitors are not effective at inhibiting further fibrous changes in the atria in patients with chronic atrial fibrillation: speculation from analysis of the time course of fibrillary wave amplitudes.

To examine whether angiotensin-converting enzyme (ACE) inhibitors are effective at inhibiting further fibrous changes in atria in patients with chronic atrial fibrillation, we retrospectively evaluated the time course of fibrillatory wave amplitudes and the effects of an ACE inhibitor on the changes. We reviewed medical records and electrocardiographic files. The patients were eligible for inclusion if they had chronic atrial fibrillation for more than 10 years. The fibrillatory wave with the greatest amplitude was measured in lead V1 of standard electrocardiograms. A total of 31 patients were enrolled and were divided into two groups according to treatment. Twelve patients were classified as the ACE inhibitor group and 19 as the non-ACE inhibitor group. There was no significant difference in the mean value of the fibrillatory wave amplitude at baseline between the 2 groups (ACE inhibitor group, 0.23 +/- 0.02 mV; non-ACE inhibitor group, 0.18 +/- 0.02 mV). The fibrillatory wave amplitude decreased significantly after 10 years in both groups (ACE inhibitor group, 0.10 +/- 0.02 mV; non-ACE inhibitor group, 0.11 +/- 0.01 mV) and the changes in the fibrillatory wave amplitude were similar between the 2 groups. These results suggest that ACE inhibitors are not effective at inhibiting further fibrous changes in atria in patients with chronic atrial fibrillation.