Boston Scientific's Cryoballoon in the Treatment of Symptomatic Drug Refractory Paroxysmal Atrial Fibrillation

Inclusion Criteria: * History of recurrent symptomatic paroxysmal atrial fibrillation (PAF), defined as atrial fibrillation that terminates spontaneously or with intervention (either procedure or drug therapy) within seven days of onset. Minimum documentation includes the following: * a physician's note indicating recurrent self-terminating atrial fibrillation (AF) which includes at least two symptomatic AF episodes within six months prior to enrollment, and one electrocardiographically documented AF episode within 12 months prior to enrollment. * No amiodarone use within 90 days prior to enrollment; * Subjects who are indicated for an ablation procedure for paroxysmal atrial fibrillation (PAF) according to 2017 HRS expert consensus statement on catheter and surgical ablation of atrial fibrillation; * Subjects refractory or intolerant to at least one class I or III antiarrhythmic medication; * Subjects who are willing and capable of providing informed consent; * Subjects who are willing and capable of participating in all testing associated with this clinical investigation at an approved clinical investigational center; * Subjects whose age is 18 years or above, or who are of legal age to give informed consent specific to state and national law. Exclusion Criteria: * Any known contraindication to an AF ablation or anticoagulation; * Continuous AF lasting longer than seven (7) days from onset; * History of previous left atrial ablation or surgical treatment for AF/ AFL/ AT; * Atrial fibrillation secondary to electrolyte imbalance, thyroid disease, or any other reversible or non-cardiac cause; * Structural heart disease or implanted devices as described below: 1. Left ventricular ejection fraction (LVEF) \< 40% based on the most recent transthoracic echocardiogram (TTE) (≤180 days prior to enrollment); 2. Left atrial diameter \> 55 mm OR left atrial volume \> 50 ml/m2 ml indexed based on the most recent TTE (≤ 180 days prior to enrollment); 3. An implanted pacemaker, ICD, CRT device or an arrhythmia loop recorder; 4. Previous cardiac surgery: i.e. ventriculotomy or atriotomy (excluding atriotomy for CABG); 5. Previous cardiac valvular surgical or percutaneous procedure, or prosthetic valve, including mitral valve clips; 6. Interatrial baffle, closure device, patch, or patent foramen ovale (PFO) occlude; 7. Presence of a left atrial appendage occlusion device; 8. Presence of any pulmonary vein stents; 9. Coronary artery bypass graft (CABG), PTCA/ PCI/ coronary stent procedures within 90 days prior to enrollment; 10. Unstable angina or ongoing myocardial ischemia; 11. myocardial infarction within 90 days prior to enrollment; 12. Moderate or severe mitral insufficiency assessed on the most recent TTE (≤180 days prior to enrollment, e.g. pulmonary artery pressure \>30 mmHg); 13. Evidence of left atrial thrombus; * Any previous history of cryoglobulinemia; * Stage 3B or higher renal disease (estimated glomerular filtration rate, eGFR \<45 mL/min); * History of blood clotting or bleeding disease; * Any prior history of documented cerebral infarct, TIA or systemic embolism \[excluding a post-operative deep vein thrombosis (DVT)\] ≤180 days prior to enrollment; * Active systemic infection; * Pregnant, lactating (current or anticipated during study follow up), or women of childbearing potential who are, or plan to become, pregnant during the time of the study (method of assessment upon physician's discretion); * Subjects who are currently enrolled in another investigational study or registry that would directly interfere with the current study, except when the subject is participating in a mandatory governmental registry, or a purely observational registry with no associated treatments; each instance must be brought to the attention of the sponsor to determine eligibility; * Subjects who in the judgment of the investigator have a life expectancy of less than two years.