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Direct Pressure Monitoring Accurately Predicts Pulmonary Vein Occlusion During Cryoballoon Ablation

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Lessons from dissociated pulmonary vein potentials: entry block implies exit block.

Mattias Duytschaever¹, Grim De Meyer, Marta Acena

¹Department of Cardiology, St Jan Hospital Bruges, Ruddershove 10, 8000 Bruges, Belgium. mattias.duytschaever@azbrugge.be

Europace : European Pacing, Arrhythmias, and Cardiac Electrophysiology : Journal of the Working Groups on Cardiac Pacing, Arrhythmias, and Cardiac Cellular Electrophysiology of the European Society of Cardiology

|January 1, 2013

Summary

This summary is machine-generated.

Residual pulmonary vein to left atrium (PV-LA) exit conduction after isolation is rare (0.6%) when entry block is definitively proven. This finding supports left atrial-pulmonary vein entry block as a sufficient endpoint for pulmonary vein isolation.

Keywords:

Atrium Electrophysiology Fibrillation

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Area of Science:

Electrophysiology
Cardiology
Medical Devices

Background:

Residual pulmonary vein to left atrium (PV-LA) exit conduction can persist after pulmonary vein isolation (PVI).
Previous studies using pacing maneuvers reported up to 42% prevalence of residual PV-LA exit conduction.
The current study investigates PV-LA exit conduction without pacing, focusing on unambiguously proven entry block.

Purpose of the Study:

To determine the prevalence of residual PV-LA exit conduction.
To assess PV-LA exit conduction in the presence of proven left atrial-pulmonary vein (LA-PV) entry block.
To evaluate if LA-PV entry block is a sufficient electrophysiological endpoint for PVI.

Main Methods:

A two-center study involving 378 patients undergoing circumferential PV isolation.
Utilized three-dimensional mapping and a circular mapping catheter.
Identified spontaneous pulmonary vein (PV) potentials as proof of LA-PV entry block, with automaticity cycle length >1000 ms.

Main Results:

Spontaneous PV potentials were observed in 132 of 378 patients (35%).
Pulmonary vein automaticity was confirmed in 171 PVs.
Spontaneous PV-LA exit conduction occurred in only 1 of 171 PVs (0.6%).
Pacing in a subset of 69 PVs confirmed PV-LA exit block.

Conclusions:

Unidirectional block at the LA-PV junction is uncommon (0.6%) when entry block is unambiguously proven.
LA-PV entry block is a sufficient electrophysiological endpoint for successful PVI.
Pacing maneuvers may overestimate the prevalence of residual PV-LA exit conduction.