1990 Volume 27 Issue 6 Pages 687-692
Atrial fibrillation is one of the arrhythmias that increase with increasing age. In this study we compared transition intervals from sinus rhythm to permanent atrial fibrillation and the time course of the f wave amplitude immediately after the transition between 32 younger (<65 years) and 44 elderly patients (≥65 years) in whom transition from sinus rhythm to permanent atrial fibrillation was confirmed on serial ECG recordings. Each group was classified into three categories according their underlying diseases; hypertensive heart disease, valvular disease, and lone atrial fibrillation. In patients with hypertensive heart disease or lone atrial fibrillation, there was no significant difference in the transition intervals between the younger and the elderly groups. In both groups the transition intervals were significantly (p<0.05) longer in patients with lone atrial fibrillation than those in patients with hypertensive heart disease (44.6 vs. 12.5 months in younger and 26.8 vs. 12.9 months in elderly). A significant positive correlation (r=0.58, p<0.01) was observed between the final P wave and the initial f wave amplitude on establishment of permanent atrial fibrillation in all patients. In the younger group, the initial f wave amplitude of patients with valvular disease (0.27±0.04 mV, mean±SE) was significantly larger than those of patients with hypertensive heart disease (0.15±0.03mV, p<0.05) and of patients with lone atrial fibrillation (0.16±0.01mV, p<0.05).The f wave amplitude of valvular disease was significantly decreased after 1 year (0.22±0.03mV, p<0.05). Even after 3 years it was signifiantly (p<0.05) larger than that of patients with two other diseases, which showed no changes during the observation period. On the other hand, in the elderly group, the initial f wave amplitudes were 0.16±0.03mV in patients with hypertensive heart disease, 0.18±0.01mV in patients with valvular disease, and 0.15±0.01mV in patients with lone atrial fibrillation. There was no significant difference in the initial f wave amplitude among all 3 diseases and no significant changes in f wave amplitude during the observation period.
