PACEMAKER MALFUNCTION

The field of cardiac pacing has expanded rapidly in recent years. Engi neering improvements and microprocessor technology have resulted in a vast increase in pacemaker technology. The ''high-tech'' edge of cardi ac pacing often discourages all but the pacemaker specialist from appr oaching a malfunctioning pacemaker. Electrocardiographic signs of pace maker malfunction can be grouped into four categories: failure to outp ut, failure to capture, undersensing, and inappropriate pacemaker rate . For each of these categories, there may be true malfunctions and pse udomalfunctions. In addition, environmental sources of electromagnetic interference, both within and outside the hospital environment, can r esult in pacemaker malfunction. Approaching pacemaker malfunction with these categories in mind should help minimize confusion.