Atrial Fibrillation Ablation The Hybrid Approach Versus Traditional Management

Summary

Rationale: To determine the most beneficial ablation methodology for individual patients with paroxysmal or persistent atrial fibrillation (defined by the Heart Rhythm Society) as surgeons and electrophysiologists work together on a convergent procedure (hybrid) to place the epicardial and endocardial ablation lines.

Objectives: Catheter and surgical ablation are being offered today to patients with drug refractory and symptomatic atrial fibrillation. This study is designed to assess the most efficient ablation approach in patients with paroxysmal and persistent atrial fibrillation. In patients with left atrium size of less than 5.0 cm, a Hybrid approach (pulmonary vein isolation performed surgically will be combined with right and left atrial flutter lines performed using a transcatheter approach) will be compared to percutaneous catheter ablation to isolate the pulmonary veins and apply the left and right atrial flutter lines with removal of LA appendage. In the group of patients with left atrial size 5.0-6.0 cm the Hybrid approach is going to be compared to the minimally invasive Cox-Maze III procedure.

Our hypotheses with regard to the rate of return to sinus rhythm off antiarrhythmic drugs at 6 months will demonstrate that the Hybrid approach is going to be a: superior to percutaneous catheter ablation in the less than 5 cm left atrial group and b: non-inferior when compared to the Cox-Maze III procedure in the 5-6 cm left atrial cm group.

We hypothesize that the safety of all procedures will show no differences and that there will be no differences in clinical complications between groups.

Conditions

• Ablation of Atrial Fibrillation

Interventions

PROCEDURE

Pulmonary vein isolation ablation procedure for atrial fibrillation

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.

PROCEDURE

Hybrid procedure for ablation of atrial fibrillation

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.

PROCEDURE

The Cox Maze Procedure for Ablation of Atrial Fibrillation

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.

PROCEDURE

Hybrid Procedure for Left Atrium >5 cm but < 6.1 cm

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.

Sponsors & Collaborators

• Inova Health Care Services

  lead OTHER

Principal Investigators

• Niv Ad, MD · Inova Fairfax Hospital

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2011-05-31

Primary Completion

2014-09-30

Completion

2014-09-30