Progress in Cardiac Pacing

Cardiac pacing therapy has evolved rapidly since the first device was implanted 26 years ago.¹Technologic progress has provided the clinician with microprocessor-based multiprogrammable pulse generators, long-lived power sources, and reliable atrial and ventricular lead systems. Along with these developments, the indications for singleand dual-chamber pacing have broadened considerably since the early pacemakers were implanted for complete heart block. They now include the bradyarrhythmic manifestations of the sick sinus syndrome and some types of tachycardias.²⁻⁴As a result, the number of patients in the United States with pacemakers is over 500,000 and growing.⁵The practicing physician is thus very likely to encounter patients who either have or need a pacing system. In the past, the physician caring for a patient was concerned primarily with establishing the indications for pacemaker implantation. Now pacing therapy must be individualized to match the patient's needs with the most suitable pacing mode