Future generation pacemakers.

Interchangeability between pacing modes will be the key feature in the pacemaker of the 1980s. The usefulness of the various modes will be enhanced by the array of pacing parameter options made available within each mode. Noninvasive adjustments of rates, AV intervals, signal detection sensitivities, and both atrial and ventricular stimulating energies will allow for necessary fine-tuning and ease of trouble-shooting throughout the life of the pacemaker system. Battery energy will be conserved by trimming output pulse characteristics to safe but reasonable levels. On the other hand, should myocardial thresholds increase, flexibility to reprogram pulse width and/or amplitude will avoid the need for reimplanting new electrodes or pulse generator. The physician will be able to evaluate underlying rhythm mechanisms and even perform single electrophysiologic studies by using special programmable features. Advanced telemetry features will facilitate patient followup and help identify pacing problems. Various telemetry options will include information on programmed and actual performance parameters, and on endocardial signals from both the atria and ventricles. Future generation pacemakers will be a collection and refinement of present technologies into single pacing systems. It is not overly optimistic to envision within this decade a small, long-life, easily implanted, sophisticated pacemaker that is capable of several modes of operation for treatment of both bradycardias and tachycardias, and is noninvasively adjustable to various and changing patient conditions.