Carotid sinus syndrome and falls in older adults

Retrospective and circumstantial evidence supports an overlap between symptoms of falls and syncope in older adults. Because of this overlap, we undertook a prospective, explanatory, single-center study of cardiac pacing for falls in patients with carotid sinus syndrome in a consecutive series of over 56,000 adult visitors to an emergency department. One third attended because of a fall; one in five fallers had unexplained falls, and one third of these had carotid sinus hypersensitivity, of whom one half had a cardioinhibitory or mixed response that may be expected to respond to cardiac pacing. In a randomized, controlled trial of a subset of these patients, cardiac pacing was shown to significantly reduce subsequent fall rates by two thirds and syncopal rates during 1-year follow-up. The current pacing rate for carotid sinus syndrome is much higher in our practice than in other series because our facility is dedicated to falls and syncope in older subjects who have direct access to referring physicians and family practitioners. Of the implants in our region, 24% are for carotid sinus syndrome, compared with 43% for atrioventricular block, 20% for sick sinus syndrome, and 12% for atrial fibrillation. These rates do not include pacing in patients who fall, but rather reflect pacing rates consistent with American College of Cardiology guidelines for carotid sinus syndrome, such as recurrent syncope. These preliminary results from a local explanatory study are now being tested in a multicenter study entitled Syncope and Falls in the Elderly: Pacing and Carotid Sinus Evaluation (SAFE-PACE II).