Crosstalk due to activation of atrial sense marker function of DDD pulse generators

Accidental atrial and ventricular stimulation by pacemaker event marker

A case of both atrial and ventricular stimulation by the sense event marker during external chest wall stimulation of a DDDR pacemaker is reported. This unusual phenomenon might produce pacemaker-mediated tachycardia.

Crosstalk during bipolar pacing

Bipolar sensing pulse generators were thought to have eliminated crosstalk problems evident in unipolar systems. Crosstalk has been observed in the Model 284-02 bipolar sensing pacemakers. These intermittent problems were resolved by decreasing atrial output, decreasing ventricular sensitivity or increasing the ventricular blanking period. Three patients had pacemaker crosstalk, two experienced symptoms analogous to pacemaker syndrome.

Termination of ventricular tachycardia by chest wall stimulation during DDD pacing. A report of two cases

This report describes the use of chest wall stimulation (CWS) for the termination of ventricular tachycardia in two patients with dual chamber pulse generators functioning in the DDD mode. Rapid CWS induced burst ventricular pacing when CWS was selectively sensed by the atrial channel, whereupon the pulse generator triggered its ventricular output. In this way, by programming the pulse generators to the maximum upper rate, this CWS technique produced burst ventricular pacing at a rate of 175 to 180/minute that successfully terminated ventricular tachycardia in both patients. The same CWS technique also initiated ventricular tachycardia by burst ventricular pacing. This CWS technique may be useful for the termination of relatively slow ventricular tachycardia in patients with DDD pulse generators when the maximum rate of ventricular pacing cannot be otherwise increased.