High degree AV block associated with timolol use in elderly patient

CLEVELAND — Elderly, frail patients on topical timolol should be watched carefully for cardiac side-effects, and the medication should be discontinued if such side-effects develop, according to a report from cardiologists here.

Use of the non-cardioselective beta-blocker timolol in frail, elderly patients has been previously reported to be responsible for unexplained bradycardia and high-degree atrioventricular (AV) block. In a case report in the International Journal of Cardiology, Mohsen Sharifi, MD, and colleagues report on the development of third-degree AV block, without ventricular escape, in an otherwise healthy patient due to topical administration of timolol. The complication required insertion a temporary pacemaker and subsequently a permanent pacemaker in the patient. According to the report, the only medication with AV nodal depressant properties in the patient’s medical regimen was timolol maleate 0.5%, which the patient had been taking continuously for a year.

The authors suggest that other topical glaucoma medications be substituted for timolol in patients with cardiac side effects. They are careful to note, however, that while a strong association of third-degree AV block with ophthalmic timolol was illustrated in this case, the overall number of patients on a timolol regimen indicates that AV block appears to be an infrequent complication.