Freedom from pulmonary vein stenosis after multiple applications of epicardial ablation energy

In patients undergoing cardiac surgical procedures, pulmonary vein isolation may be easily accomplished, and it is important to achieve bidirectional conduction block across created lesions. The primary aim of this study was to assess the risk of pulmonary vein stenosis (PVS) after multiple applications of epicardial bipolar radiofrequency energy.

Thirty-five consecutive patients who were referred for off-pump coronary revascularization with concomitant pulmonary vein isolation and left atrial appendage occlusion were prospectively included in the study. The ablation protocol provided 8 standard epicardial applications of bipolar energy with additional applications until the acute bidirectional conduction block was achieved. Three to 6 months after surgery, patients underwent computed tomography to assess PVS.

In all patients, bidirectional conduction block was achieved across the created lesions. In 31 (89%) patients, conduction block was accomplished after the standard 8 energy applications on each side. In 4 (11%) patients, additional applications of energy were needed. All patients had computed tomography (128 total pulmonary veins) scans, which showed no evidence of PVS.

Multiple applications of bipolar radiofrequency energy during off-pump epicardial pulmonary vein isolation did not lead to PVS. Creating bidirectional conduction block using multiple energy applications through created lesions is feasible in all patients using the ablation protocol described.