STOP AF First: Cryoballoon Catheter Ablation in an Antiarrhythmic Drug Naive Paroxysmal Atrial Fibrillation

Treatment success after AAD initiation (control arm) or pulmonary vein isolation ablation procedure utilizing the Arctic Front Advance™ Cardiac CryoAblation Catheter (treatment arm). Treatment success is the opposite of treatment failure. Treatment failure was defined as any of the following: * Acute procedural failure (treatment arm only). * Documented AF/AT/AFL on ambulatory monitoring/12-lead ECG after the 90-day post-ablation blanking period (treatment)/AAD optimization period (control arm). Minimum of 30 seconds on ambulatory monitoring or 10 seconds on 12-lead ECG. * Any subsequent AF surgery or ablation in the left atrium. * Any subsequent cardioversion after the 90-day post-ablation blanking period (treatment)/AAD optimization period (control arm). * Class I or III antiarrhythmic drug (or sotalol) use after the 90-day blanking period (treatment arm only).

Time frame: Randomization to 12 months

Population: Subjects who were received the treatment they were randomized to (modified intent to treat).

Measured by rate of composite list of serious adverse events in cryoablation-treated as randomized arm. Includes: * TIA within 7 days * Cerebrovascular accident within 7 days * Major bleed that requires transfusion or results in a 20% or greater fall in hematocrit (HCT) within 7 days * Development of a significant pericardial effusion within 30 days. (One that results in hemodynamic compromise, requires elective or urgent pericardiocentesis, or results in a 1-cm or more pericardial effusion as documented by echocardiography). * Symptomatic PV stenosis within 12 months; accompanied by one of the following: 50%-75% reduction in diameter of the pulmonary vein, with symptoms not explained by other conditions; OR \>75% reduction in diameter of the pulmonary vein * MI within 7 days * PNI unresolved at 12 months * AE fistula within 12 months * Major vascular complication that requires intervention, prolongs hospital stay, or requires hospital admission (within 7 days).

Time frame: Randomization to 12 months

Population: Subjects who were cryoablation-treated as randomized (as was pre-specified in both the protocol and Statistical Analysis Plan)

Compare health care utilization between the treatment and control arms. There are two hypotheses tested in the objective, with separate hypothesis tests for: (1) the rate of total health care utilization events (cardiovascular-related hospitalizations, emergency room visits, or unscheduled office visits) over 12 months shown as freedom from cardiovascular health care utilization by treatment arm, and (2) freedom from cardioversions (electrical or pharmacological) over 12 months by treatment arm.

Time frame: Initial treatment through 12 months.

Population: All subjects treated as randomized (mITT).

There are two hypotheses tested in the objective, with separate hypothesis tests for (1) the difference in composite scores from the AFEQT questionnaire taken at baseline and 12 month visits, and (2) for the difference in composite scores for the EQ-5D questionnaire taken at baseline and 12-month visits. Composite AFEQT score is on a scale of zero to one hundred. Higher scores are better. Composite EQ-5D score is on a scale of zero to one. Higher scores are better.

Time frame: Baseline and 12 Months

Population: Subjects treated with cryoballoon catheter ablation as randomized (as was pre-specified in both the protocol and Statistical Analysis Plan) and who had QOL score available at both baseline and 12 month time points.