Validation Durability Adenosine Effect in Verification Pulmonary Vein Isolation

Adenosine is used clinically to assess permanency of electrical isolation of pulmonary veins during atrial fibrillation ablation, however, the methodology has not been validated either in terms of the reproducibility of the adenosine response or the effect on clinical outcomes, namely whether using pulmonary vein reconnection to guide additional ablation lowers rate recurrent atrial fibrillation post ablation. Study will test the hypothesis that the response to adenosine used in this manner is reproducible over time.

Patients undergoing pulmonary vein isolation as part of atrial fibrillation ablation will be randomized to treatment and control groups. Treatment group subjects will received 12 mg IV adenosine to evaluate pulmonary vein reconnection after initial electrical isolation is documented. If electrical reconnection is not observed at 5 minutes, a second dose of adenosine will be administered, monitoring again for electrical reconnection. Control patients will be observed for 10 minutes post initial electrical isolation of the pulmonary vein for spontaneous electrical reconnection. If reconnection is observed, veins will be re-isolated per standard clinical practice. This procedure will be repeated for each of a patient's pulmonary veins. Patients will be followed up at clinical visits to examine for adverse effects of procedure and/or adenosine administration as well as atrial fibrillation recurrence.

25 patients will be randomized to received 2 doses of adenosine 12 mg IV, 5 minutes apart after pulmonary vein isolation. During this time, will monitor for pulmonary vein reconnection, second dose of adenosine will be given only if no reconnection after initial dose.

25 patients will be randomized to 10 minute period of observation for pulmonary vein reconnection after documentation of pulmonary vein isolation. This will serve as the control arm.

In the adenosine arm, 25 patients will be randomized to received 2 doses of adenosine 12 mg IV, 5 minutes apart after pulmonary vein isolation. During this time, will monitor for pulmonary vein reconnection, second dose of adenosine will be given only if no reconnection after initial dose. In the observation arm, 25 patients will be randomized to 10 minute period of observation for pulmonary vein reconnection after documentation of pulmonary vein isolation.

In treatment group, 30 minutes after all veins confirmed to be isolated with lasso catheter, 12 mg IV adenosine will be given to treatment group subjects, will monitor with lasso catheter for pulmonary vein reconnection for 5 minutes after adenosine administration.

In treatment group, 30 minutes after all veins confirmed to be isolated with lasso catheter, 12 mg IV adenosine will be given to treatment group subjects, will monitor with lasso catheter for pulmonary vein reconnection for 5 minutes, if no reconnection, a second dose adenosine will be given and will monitor for additional 5 minutes for pulmonary vein reconnection. Criteria for pulmonary vein reconnection will be recurrence of local pulmonary vein electrical recordings noted on lasso catheter located within the vein. Pulmonary vein isolation is defined as disappearance of all local intracardiac electrograms within a pulmonary vein recorded on a 10 electrode circular catheter or lasso catheter positioned within the vein.

Pulmonary vein reconnection will be monitored for 5 minutes post second dose of adenosine, or on average for 15 minutes after initial electrical isolation of the pulmonary vein.

Inclusion Criteria: Patients undergoing atrial fibrillation ablation, pulmonary vein isolation by catheter for standard clinical indications Exclusion Criteria: allergy or contraindication to adenosine, inability to give informed consent, currently taking dipyridamole, verapamil or theophylline and breast-feeding mothers.