Prevalence of retrograde conduction in XXXX after DDD pacemaker implantation.

@entity1 @entity591 @entity955 @entity616
Electrophysiologic studies were performed before DDD pacemaker implantation in 50 @entity1 with symptomatic @entity616 . The @entity1 were separated into 2 groups. Group I consisted of @entity1 with intact retrograde conduction and group II consisted of @entity1 with blocked retrograde conduction. After pacemaker implantation, postventricular atrial refractory periods in @entity1 in group I were programmed at 50 to 100 ms, in excess of the retrograde conduction times measured during electrophysiologic studies. In group II @entity1 , postventricular atrial refractory periods were routinely programmed at 300 ms. During follow-up, @entity1 visited the outpatient clinic at 3-month intervals for noninvasive assessment of the prevalence of retrograde conduction, and to test the inducibility of pacemaker-mediated @entity591 . The mean follow-up of group I (15 @entity1 ) was 27 +/- 10 months, whereas the mean follow-up of group II (35 @entity1 ) was 19 +/- 9 months. The mean number of noninvasive tests performed during follow-up was 8 +/- 3 per @entity1 for group I and 5 +/- 3 per @entity1 for group II. In group I, retrograde conduction remained intact in 12 @entity1 (p less than 0.01). In 29 of 31 @entity1 in group II, retrograde conduction remained absent (p less than 0.01). In 4 @entity1 in group II, chronic @entity955 occurred during follow-up. @entity955 did not occur in any @entity1 in group I. During serial electrophysiologic testing, no pacemaker-mediated @entity591 could be induced in any @entity1 in group I or II.(ABSTRACT TRUNCATED AT 250 WORDS)
