Study: NCT01298986

Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: Pulmonary vein isolation ablation procedure for atrial fibrillation
Description: The catheters will be introduced to the right atrium using the femoral vein as an access. Following a trans-septal puncture, ablation catheters will be placed in the left atrium under appropriate imaging and anticoagulation conditions (Standard of care). Following the positioning of the ablation catheters in the left heart cavity ablation to achieve PVI and left atrial isthmus line are going to be performed. Following the appropriate protocol of mapping and AF induction the right sided isthmus is going to be ablated to achieve a flutter line ablation as well. Following the procedure and following the appropriate standard of care protocols, the catheter are going to be retrieved and the procedure will be concluded. The left atrial appendage will be managed surgically. All ablation lines will be placed according to their current standard of practice using radiofrequency ablation technology and based on CARTO mapping.

Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: Hybrid procedure for ablation of atrial fibrillation
Description: The endoscope will be passed though a small port in the right thoracic cavity to the beating heart. The pericardium will be opened, the coronary sinus transected. The ablation catheters will pass underneath the SVC and IVC establishing access to the transverse and oblique sinuses. A box lesion will be epicardially placed around the pulmonary veins using cryothermia. An additional lesion line will be placed from the box lesion to the left atrial appendage. The ablation catheter will be left in place to guide the EP physicians in placing the right and left atrial flutter lines using radiofrequency. Electromagnetic mapping using a CARTO system and measuring for conduction block of the pulmonary veins will be conducted by the EP's. A second small port will then placed in the left thoracic cavity and the pericardium on the left side will be opened and the left atrial appendage will be ablated with the use of a clip placed around the left atrial appendage and tightened.

Intervention type: PROCEDURE
Group type: ACTIVE_COMPARATOR
Intervention: The Cox Maze Procedure for Ablation of Atrial Fibrillation
Description: A 7-cm incision is placed and the chest is entered through the 4th or 5th intercostal space. The femoral artery and femoral vein are cannulated. The pericardium is opened. Cardiopulmonary bypass is instituted. The right sided lesions are applied using 3 purse-strings that are placed over the right atrial free wall. The right and left atrial lesions are done using cryoablation using either nitrous oxide or Argon. Next the left atrium is entered through a standard atriotomy placed in the interatrial groove. The base of the left atrial appendage is cryoablated and connected to the left upper pulmonary vein. All four pulmonary veins are then encircled using multiple application of cryo. An endocardial cryolesion is then placed posteriorly down to the level of the mid-mitral valve annulus and an epicardial cryolesion is placed on the coronary sinus directly across the atrial wall from the endocardial lesion. The left atrial appendage is then surgically managed.

Intervention type: PROCEDURE
Group type: EXPERIMENTAL
Intervention: Hybrid Procedure for Left Atrium >5 cm but < 6.1 cm
Description: The endoscope will be passed though a small port in the right thoracic cavity to the beating heart. The pericardium will be opened, the coronary sinus transected. The ablation catheters will pass underneath the SVC and IVC establishing access to the transverse and oblique sinuses. A box lesion will be epicardially placed around the pulmonary veins using cryothermia. An additional lesion line will be placed from the box lesion to the left atrial appendage. The ablation catheter will be left in place to guide the EP physicians in placing the right and left atrial flutter lines using radiofrequency. Electromagnetic mapping using a CARTO system and measuring for conduction block of the pulmonary veins will be conducted by the EP's. A second small port will then placed in the left thoracic cavity and the pericardium on the left side will be opened and the left atrial appendage will be ablated with the use of a clip placed around the left atrial appendage and tightened.