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Right ventricular apical lead position is associated with prolonged signal-averaged P-wave duration
Mark A Maraschiello1, Damian P Redfearn, Adrian M Baranchuk
1Arrhythmia Service, Queen's University, Kingston General Hospital, Kingston, Ontario, Canada.
Aim:
The study aimed to determine if right ventricular apical pacing is associated with adverse change in atrial substrate compared with right ventricular septal pacing.
Methods:
Patients with septal leads and dual-chamber devices with more than 3 months of follow-up and 70% or higher cumulative percentage of ventricular pacing were compared with a matched group of apically implanted leads with a cumulative percentage ventricular pacing of 70% or higher. Device parameters were recorded, and high-resolution recordings were obtained for signal-averaged P-wave (SAPW) analysis. Previously obtained SAPW recordings taken from 49 healthy patients and 73 patients with paroxysmal atrial fibrillation were used as negative and positive controls, respectively.
Results:
Ten patients with septal leads (mean age, 71.9 +/- 12.1 years; mean months implanted, 10.5 +/- 3.2 months) and 9 patients with apical leads (mean age, 71.9 +/- 5.7 years; mean months implanted, 11.4 +/- 6.4 months) were enrolled. The SAPW duration was longer in the apical cohort compared with the septal cohort (144.8 +/- 6.9 and 133.0 +/- 5.5 milliseconds, respectively; P = .001), whereas there was no significant difference between septal and normal cohorts (133.0 +/- 5.5 and 129.3 +/- 7.1 milliseconds, respectively; P = .08).
Conclusions:
Apical pacing is associated with prolonged P-wave duration relative to septal pacing and controls: this may manifest as increased risk of atrial tachycardias and presents a potentially novel benefit of septal pacing.
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