LONG-TERM SURVIVAL OF VDD PACING

All patients with VDD systems implanted at a tertiary pacing center we re identified from a computer database and data collected on pacing in dications, follow-up duration, rate response, reasons for programming changes, and implant P wave amplitudes. Results: 366 implants were ide ntified for which complete data were available for 335 leads implanted in 316 patients. The mean follow-up period was 24.1 months, and age a t implant was 73.5 +/- 11.8 years. During follow-up, IB patients died (6%) and 62 (19.6%) were followed elsewhere. Indications for pacing we re complete heart block, 56.6%; intermittent AV block, 21.8%; postabla tion complete heart block, 5.4%; 2:1 AV block, 13%; and others, 3.2%. Two groups: no mode change (NMC, n = 280) and mode change (MC, n = 36) were identified. Reasons for reprogramming in the MC group were as fo llows: atrial sensing, 11; AF/atrial flutter, 18; chronotropic incompe tence, 3; and others 4. Significantly more MC patients had rate respon se programmed ON (44.4% vs 22.1%, P < 0.05). No significant difference s between the two groups were found in other variables, including male gender (55.5% vs 54.6%), length of follow-up (27.1 +/- 17.8 vs 23.8 /- 20.6 months), age at last follow-up (72 +/- 12.3 vs 75.9 +/- 11.9 y ears), and P wave amplitude (1.7 +/- 0.9 vs 1.8 +/- 0.9mV). Conclusion : Reprogramming of VDD systems is infrequent. When necessary, it is us ually prompted by atrial arrhythmias or failure of atrial sensing. Whe n adequate atrial chronotropy has been verified, VDD is an acceptable alternative to DDD pacing and survives well over the long term.