Long-term performance of single-pass physiological pacing.
BACKGROUND
Single-pass physiological pacing has several advantages over dual-lead physiological pacing. The present study evaluated the long-term performance of single-pass pacing using the overlapping biphasic impulse stimulation technique.


RESULTS
A total of 30 patients with single-pass VDD pacing and 8 patients with single-pass DDDC pacing were followed up for 1 year by basal and magnet electrocardiograms and real-time telemetry. All the patients showed satisfactory atrial sensing and pacing capture threshold. The atrial sensing thresholds at implant and at 1 month, 3 months, 6 months and 12 months of follow-up were 2.5+/-0.67 mV, 1.6+/-0.6 mV, 1.1+/-0.5 mV, 1.0+/-0.5 mV and 1.0+/-0.04 mV, respectively. The corresponding values for atrial pacing threshold at a pulse wave of 0.5 ms were 2.5+/-1.0 V, 4.4+/-0.9 V, 3.8+/-1.2 V, 3.6+/-1.4 V and 3.8+/-1.4 V. Of the patients with DDDC pacing, 88% showed stable pacing capture in the supine position, 75% in the upright position and 62% in both positions. Diaphragmatic contraction was seen in 25% of cases with DDDC pacing. No such event was seen in patients with VDD pacing.


CONCLUSIONS
Single-pass pacing is safe, technically easy and cheap as compared to dual-lead systems. However, it would be prudent to recommend DDDC pacing in patients who require predominantly VDD pacing and only occasionally atrial pacing, as the latter showed a low percentage of stable atrial pacing capture in both upright and supine positions as well as a significant percentage of diaphragmatic contraction.
Kar
A K
AK
Department of Cardiology, IPGMER, Kolkata, West Bengal.
Roy
D
D
Mondal
M
M
Dutta
I
I
D000328:Adult; D000368:Aged; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006327:Heart Block / Q000503:physiopathology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012684:Sensory Thresholds / Q000502:physiology; D013997:Time Factors