Subjects undergoing cardiac ablation procedure with the Boston Scientific Cardiac Cryoablation System.

The Boston Scientific Cardiac Cryoablation System is intended for ablation and electrical mapping of the pulmonary veins for pulmonary vein isolation (PVI) in the ablation treatment of patients with paroxysmal atrial fibrillation (PAF).The main devices and components of the system consists of the following:

• POLARx™ or POLARx™ FIT Cryoablation Catheter
• POLARMAP™ Catheter
• POLARSHEATH™
• SMARTFREEZE™ Console
• Diaphragm Movement Sensor (DMS)
• Related Accessories

This measure reports the observed safety event-free rate at 12 Months follow up for all treatment and intent subjects. The safety events are a composite of procedure-related and device-related adverse events. Acute Primary Safety Endpoints include:

• Death
• Myocardial infarction (MI)
• Persistent gastroparesis/injury to vagus nerve
• Transient ischemic attack (TIA)
• Stroke/Cerebrovascular accident (CVA)
• Thromboembolism/ Air embolism
• Cardiac tamponade/perforation
• Pneumothorax
• Serious vascular access complications
• Pulmonary edema/heart failure
• AV block not attributable to medication effect or vasovagal reaction

Chronic Primary Safety events (through 12 Months) include:

• Atrial esophageal fistula
• Pulmonary vein stenosis (≥ 70% reduction of diameter) OR presented by patient's symptoms at 12-Month follow-up and requiring intervention

This measure reports the observed failure-free rate at 12 Months post index procedure. Failure defined as:

• Failure to achieve acute procedural success in the index procedure
• Any documented recurrent AF episode(s), or new onset of AFL or AT events:
• ≥ 30 seconds in duration from any clinical recording devices considered standard of care at the study center (excluding insertable loop recorders)or
• ≥10-second of continuous AF, AFL or AT documented on any 12-lead ECG between Days 91 and 12-Month follow-up
• Any of the following interventions for atrial fibrillation, or new onset of atrial flutter or atrial tachycardia between days 91 and 12 Month Follow Up:
• Repeat procedure
• Electrical and/or pharmacological cardioversion for AF/AFL/AT
• Prescribed a higher dose of any AAD documented at baseline or a new AAD not documented at baseline.
• Hospitalization for AF/AT/AFL