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Repetitive ventricular tachyarrhythmia: result of pacemaker failure.

To the Editor.— The use of the demand feature in pacemakers has reduced, but not eliminated, problems of arrhythmias. 1 Premature battery depletion and failure of electronic components have continued to be significant problems. We observed an early and unexpected manifestation of pacemaker failure, which was permitted to continue primarily due to a low "threshold" of suspicion, and an unfortunate attitude of faith that the situation would improve. Report of a Case.— A 64-year-old man complained of increasing fatigue, dyspnea on exertion, and orthopnea. No history of angina pectoris, myocardial infarction, or rhythm disturbance could be elicited. Findings included the following: blood pressure (BP), 130/70 mm Hg; pulse rate, 45 beats per minute; cannon waves in the jugular veins; a systolic ejection murmur; and an increase in the transverse diameter of the heart by x-ray film. An electrocardiogram revealed normal sinus rhythm, complete heart block, and idioventricular rhythm at a