Drug Therapy May Help to Prevent Cardiac Conduction Disease

Does pharmacotherapy have the potential to reduce the incidence of cardiac conduction abnormalities? To find out, researchers conducted a partly industry-funded secondary analysis of serially obtained 12-lead electrocardiographic data from the 21,004 ALLHAT participants (mean age, 66.5; 56% men) who had hypertension and at least one other cardiac risk factor. The participants had been randomly assigned to receive antihypertensive therapy with amlodipine, lisinopril, or chlorthalidone.

During follow-up, incident conduction-system defects were identified in 1114 participants: 389 with left bundle-branch block, 570 with right bundle-branch block, and 155 with intraventricular conduction delay. Compared with participants assigned to chlorthalido…