Pacing-related acute pulmonary edema and mechanical asynchrony illustrated by three-dimensional echocardiography.

Sick sinus syndrome with symptomatic bradycardia is an indication for a permanent pacemaker. Either a single (AAIR) or dual-chamber (DDDR) pacemaker can be implanted in these patients with normal atrioventricular nodal function. This report presents a 92-year-old male with right ventricular apical pacing related recurrent acute pulmonary edema and mechanical asynchrony demonstrated by three-dimensional echocardiogram. Although three-dimensional echocardiography has been available for many years, it has seldom been applied to evaluate pacing-related intraventricular asynchrony. The systolic asynchrony index for this patient was 6.7% during AAIR pacing mode and 22% during DDDR pacing mode.