Palpitations and fatigue in a football player.

An 18-year-old college football linebacker reported to the training room physician's office in early September complaining of an irregular heartbeat and lightheadedness while weightlifting. He also noted mild fever and chills and rapid fatigability during practice. He said that he had had a skin eruption several weeks earlier. He denied chest pain or pressure, near syncope or syncope, shortness of breath, or history of palpitations.

Suppression of ventricular output by noise in the atrial channel in a dual chamber pacemaker.

In a pacemaker dependent, 60-year-old man with complete heart block, programming high (5.0 V and 1.0 ms) atrial output and 5.0 volt and 0.5 ms ventricular output while in the DDD mode of a pulse generator, resulted in loss of ventricular channel output with resulting asystole, while the simultaneous, pulse generator produced ECG interpretation channel falsely indicated continuing ventricular channel output. Ventricular pacing was promptly restored by programming to the emergency VVI mode. At later operation the atrial lead was determined to be defective, with a low impedance, while the ventricular lead was intact (lead impedance telemetry was not available). The manufacturer has acknowledged a pulse generator design anomaly that may occur in the setting of a low atrial impedance and issued a Health Safety Alert.

Long-term management of ventricular tachycardia by implantable automatic burst tachycardia-terminating pacemakers.

This report describes the long-term follow-up of two patients who received implantable automatic burst tachycardia-terminating ventricular pacemakers for the treatment of drug-refractory sustained ventricular tachycardia. After implantation, both pulse generators continued to terminate ventricular tachycardia without any major complications. In one patient, after three years, many episodes of ventricular tachycardia were slower than the tachycardia-detection criterion rate of 137 per minute; ventricular tachycardia was then terminated by chest wall stimulation that activated the burst function of the pacemaker. In this particular patient, the pulse generator was removed after four and one-half years and replaced with a DDD system because of the pacemaker syndrome and attacks of ventricular tachycardia, often at a rate of about 100/minute. In the second patient, the pacemaker continued to terminate ventricular tachycardia for over five and one-half years as determined by the repeated activation of the flag (memory) function of the pacemaker indicating detection of tachycardia by the pulse generator and resultant delivery of burst pacing.

Intermittent tachycardia-dependent combined right bundle branch and left anterior conduction block.

A patient is described who had intermittent tachycardia-dependent combined right bundle branch and left anterior conduction block (left axis deviation) with simultaneous onset and disappearance during observations extending over 15 months. Although the site of conduction block could not be definitely determined the pathologic and electrophysiologic data suggest that there was a lesion in the distal part of the His bundle, presumably in fibers already arranged and predestined to supply the right bundle branch and left anterior areas. A single lesion at the so-called pseudobifurcation or two separate lesions with similar electrophysiologic consequences could also account for the observations.