Cardiac pacing.

The symptom most frequently requiring investigation and consideration for cardiac pacing is syncope. This symptom is now receiving more attention than ever, mainly because of the advent of tilt table testing--a simple noninvasive procedure that has substantially reduced the number of syncopal patients remaining undiagnosed. The first part of this review addresses developments in the understanding of syncope, and the latter part covers developments in the understanding and therapy of atrioventricular block and sinus node disease, the management of carotid sinus syndrome, and two possible new indications for pacemaker therapy.