Double blind crossover comparison of the effects of dual chamber (DDD) and ventricular rate adaptive (
VVIR) pacing on neuroendocrine variables, exercise performance, and symptoms in complete heart block.
Seven patients had DDDR pacemakers (Medtronic, n= 4; Vitatron, n=1; Biotronik, n=2) and 25 patients had
VVIR pacemakers (Medtronic, n=13; St.
Since the patient had good intrinsic sinus rhythm at a rate of 55 bpm and potential complication risk during a subsequent lead revision, which was also refused by the patient, we reprogrammed the generator to
VVIR mode that was well tolerated by the patient during follow-up.
Pacing modes were
VVIR in 72%, VDD in 13%, AAIR in 8%, and DOD in 7% of patients atthe initial implantation time.
Of 40 pacemakers 15 were programmed to
VVIR, 11 DDDR, 7 DDD, and 7 VDDR modes.