December 1, 1990Pacing and Clinical Electrophysiology
Dynamic Electrophysiology of Ventriculoatrial Conduction: Implications for DDD and DDDR Pacing
Key result
Exercise and posture changes are linked to an increase in 1:1 ventriculoatrial conduction to 76%.
- n=17
Why the study?
The behavior of ventriculoatrial conduction during exercise and its implications for dual chamber pacemaker technology and programming remain unknown.
Does exercise alter ventriculoatrial conduction characteristics in patients with or requiring dual chamber pacemakers?
Population
17 patients undergoing electrophysiological study of AVC and VAC
Comparison
VAC behavior at supine rest, upright position, and during cycloergometric exercise at increasing pacing rates
Design
Observational electrophysiological study
Authors
Discussion
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Implication
Unpredictable exercise VAC in DDD patients warrants individualized PVARP assessment; small cohort data leave optimal programming strategies open.
Study Design
Type
Observational (n=17)
Structured PICO
Does exercise alter ventriculoatrial conduction characteristics in patients with or requiring dual chamber pacemakers?
P
Population
17 patients (10 preimplantation and 7 with a DDD pacemaker) undergoing an electrophysiological study of atrioventricular and ventriculoatrial conduction during rest, standing, and exercise.
E
Exposure
Electrophysiological study of atrioventricular and ventriculoatrial conduction during supine rest, upright position, and cycloergometric exercise at progressively increasing pacing rates
O
Outcome
Wenckebach points (AVC-W and VAC-W) and conduction times (AVCT and VACT) as a function of pacing ratesurrogate
Main Result
Absolute Event Rate: 76% vs 41%
Exercise induces dynamic changes in ventriculoatrial conduction that cannot be predicted from resting data, highlighting the risks of relying solely on long PVARP or auto-adaptive PVARP algorithms for pacemaker-mediated tachycardia protection.
Cite This Study
Cazeau et al. (1990) conducted an observational in Patients undergoing pacemaker implantation or with an existing DDD pacemaker (n=17). Exercise and postural changes vs. Supine rest was evaluated on 1/1 ventriculoatrial conduction (VAC). Exercise and postural changes increased the presence of 1/1 ventriculoatrial conduction from 41% at rest to 76% during exercise, shortening conduction time and improving the Wenckebach point by 33%.