Comparison of Hybrid Ablation and Pulmonary Vein Isolation Alone vs Hybrid Ablation With PVI Plus Catheter Ablation

Atrial fibrillation (AF) is one of the leading causes of stroke and heart failure. It is also
a major cause of hospitalizations and mortality (Stewart, Wattigney, and Wolf). Patients with
atrial fibrillation (AF) who are intolerant to Class I and III antiarrhythmic drugs often
require endocardial ablation, which can include pulmonary vein isolation (PVI) using
radiofrequency (RF) catheter ablation or cryoballoon ablation (Medtronic, MN) and reported
success rates vary (Calkins et al). In patients with persistent and long standing persistent
AF success rates may not be as high (Akoum et al) and there is little data analyzing outcomes
for patients in this population (Calkins et al). Using an epicardial-endocardial, or hybrid,
approach Gehi et al describes a 66% 12 month arrythmia-free survival rate following the
procedure, with 37% patients still on antiarrythmic drug therapy at 12 months. Furthermore, a
paper by Anderson et al reports that the hybrid ablation results in lower costs and higher
quality adjusted life years for patients with non-paroxysmal AF as reported by the studie's
results of fewer repeat ablations and maintenance of sinus rhythm at 5 years. Conflicting
reports exist on how much endocardial catheter ablation is needed for patients in persistent
and long standing persistent AF. Verma et al reports results for patients in persistent AF
having endocardial PVI compared to P VI plus additional linear lesions. Eighteen month
success rates for these patients were 59% and 46% respectively.

Success of surgical hybrid ablation using epicardial ablation cocontaminent with endocardial
PVI alone versus the hybrid approach using epicardial ablation with endocardial ablation
consisting of PVI ablation and RF ablation has not been studied using a randomized,
prospective approach.

If it is found that the PVI alone is as effective as PVI plus additional catheter ablation
for patients receiving a hybrid ablation, it may reduce the need for extensive catheter
ablation, thereby reducing the radiation exposure, procedure time, and radiofrequency
ablation time.

Inclusion Criteria:

- The subject is 18 years of age or older

- Left atrium < 6.0 em (Trans Thoracic Echo - TTE- parasternal4 chamber view performed
within 6 months)

- History of AF for at least 6 months

- Failed or refractory to one AAD (class I and/or Ill)

- Documentation of persistent AF

- Provided written informed consent

- Be eligible for the hybrid procedure

Exclusion Criteria:

- Pregnant or planning to become pregnant during study

- Co-morbid medical conditions that limit one year life expectancy

- Previous cardiac surgery

- Previous abdominal surgery which will prevent epicardial access

- History of pericarditis

- Previous cerebrovascular accident (CVA), excluding fully resolved TIA

- Patients who have active infection or sepsis

- Patients with esophageal ulcers strictures and varices

- Patients with renal dysfunction who are not on dialysis (defined as GFR ::5 40)

- Patients who are contraindicated for anticoagulants such as heparin and coumadin

- Patients who are being treated for ventricular arrhythmias

- Patients who have had a previous left atrial catheter ablation for AF (does not
include ablation for AFL or other supraventricular arrhythmias)

- Current participation in another clinical investigation of a medical device or a drug,
or recent participation in such a study within 30 days prior to study enrollment

- Not competent to legally represent him or herself (e.g., requires a guardian or
caretaker as a legal representative)