High prevalence of symptomatic bradyarrhythmias due to atrioventricular node-fascicular and sinus node-atrial disease in patients with mitral anular calcification.

Mitral anular calcification (MAC) is associated with high frequency of conduction defects. To delineate this association in patients with symptomatic bradyarrhythmias, 68 consecutive patients requiring pacemakers (group I) and 56 matched controls (group II) were studied. The patients comprised 41 men and 27 women, whose ages ranged from 24 to 92 years (mean 68). The control group consisted of 56 subjects without bradyarrhythmias, whose ages ranged from 30 to 86 years (mean 70); there were 36 men and 20 women. MAC was detected in 59 patients (87%) with symptomatic bradyarrhythmias compared with 8 subjects (14%) in the control group. In group I, 15 patients (22%) had complete atrioventricular block, 23 patients (34%) had atrial fibrillation with slow ventricular response, and 30 patients (44%) had intermittent sinus arrest. The incidence of MAC was similar among these subgroups (93%, 83%, and 87%, respectively). Thus the present study confirms the strong association of MAC with symptomatic bradyarrhythmias.