Cardiac pacing: atrial fibrillation may go unrecognised

摘要

The first successful cardiac resuscitation by external stimulation was reported in the 1950s, and the medical importance of electrical cardiac stimulation grew rapidly. Worldwide, millions of people with cardiac arrhythmias have been treated with pacemakers. Over the same period, large prospective randomised trials have shown that anticoagulation with warfarin lowers the risk of thrombo-embolic stroke by 70% in patients with atrial fibrillation (AF).1 Despite clear guidelines, anticoagulation is underused in patients with AF in various clinical settings.2 Electrocardiographic recognition of the underlying rhythm in patients with sick sinus syndrome (SSS) who have ventricular pacing can be difficult. Tse and colleagues3 studied 226 unselected paced patients with dual-chamber-rate-responsive devices. During a mean follow-up of 84 months, 99 patients (44%) had at least one episode of AF, compared with 0.4% in the general population. Patients with AF had 2.5 times more cardiovascular events and a ten times greater incidence of persistent AF than the other patients in the study.Sparks and colleagues4 reported a similar prevalence of AF (48%) in a smaller series of outpatients with pacemakers. The growth in use of cardiac pacing will increase the need of awareness for the possibility of unrecognised AF episodes.