Potential candidates for pacemakers. Survey of heart block and sinoatrial disorder (sick sinus syndrome).

Abstract

Future pacemaker requirements in Britain are related to the incidence of heart block and sinoatrial disorder (sick sinus syndrome) in the community. An 8 yr survey of these conditions by direct approach to the general practitioners looking after approximately 600,000 people was reported. The patients were divided into 4 non-exclusive groups (numbers of patients are in parentheses); chronic complete heart block (436), sinus bradycardia (potential and established sinoatrial disorder) (305), established sinoatrial disorder (131) and paced patients (209). Patients with sinoatrial disorder and sinus bradycardia were some 10 yr younger than those with heart block and their prevalence tended to decline in the very old, whereas the prevalence of heart block continued to increase almost exponentially, exceeding 5/1000 in men aged 80 and above. Only a minority of patients gave a past history of cardiac infarction or diphtheria, but both conditions were commoner in sinoatrial disorder (16 and 14%, respectively) than in complete heart block (9 and 8%, respectively). A surprising finding was that men predominated in all groups, particularly in those with sinus bradycardia where the male:female ratio was 2.5:1. The annual number of new paced patients rose during the course of the survey, reaching 73/106 (per yr) by the 7th and 8th years, but the annual incidence of conditions producing bradycardia and potentially requiring pacemaker therapy was still much greater at 159-174/106 of the population.