Stop AF Cardiac Ablation for Atrial Fibrillation

The Stop AF trial and Stop AF post approval study assessed the safety and effectiveness of the Arctic Front and Arctic Front Advance Cardiac Cryoablation Catheters.

Stop AF trial1

The Sustained Treatment of Paroxysmal Atrial Fibrillation (Stop AF) Trial was designed to confirm the safety and effectiveness of the first generation Arctic Front™ Cardiac Cryoablation System when used to treat patients with drug-refractory, recurrent symptomatic paroxysmal atrial fibrillation (PAF). Outcomes of this trial resulted in FDA approval of the cryoballoon in the U.S.

Stop AF trial monitoring/study follow-up

Safety and effectiveness assess through 12 months of follow-up.

STOP AF table

First generation cryoballoon outcomes:
Stop af primary effectiveness

Primary effectiveness at 12 months

The first generation cryoballoon trial showed  improved outcomes relative to drug.

  • 3.1% rate of cryoablation procedure events and 3.1% major AF events in the ablation arm
  • Compared to the drug arm, which had 8.5% major AF events

Primary effectiveness
Freedom from AF at 12 Months

Primary effectiveness at 12 months


The STOP AF trial demonstrated that cryoballoon ablation is a safe and effective alternative to antiarrhythmic medication for the treatment of patients with symptomatic paroxysmal AF, for whom at least one anti-arrhythmic drug has failed, with risks within accepted standards for ablation therapy.

Stop AF post approval study3

The Stop AF post approval study (PAS) is the largest prospective FDA multicenter study in North America to assess long-term safety and effectiveness of the Arctic Front Advance™ Cardiac Cryoablation Catheter System in the treatment of patients with drug-refractory, recurrent, symptomatic paroxysmal atrial fibrillation. The primary objectives are effectiveness (freedom from AF) at 36 months and safety (cryoablation/procedure related events) at 12 months. 

Stop AF PAS monitoring/study follow-up


Second generation cryoballoon outcomes: Stop af post approval study primary effectiveness

2-year interim analysis

Results demonstrate Arctic Front Advance Cryoballoon safety, efficacy, and suggest lesion durability in patients with drug-refractory recurrent symptomatic PAF. 

  • 5.8% (20/344) adverse event rate, of which 3.2% (11/344) PNI unresolved at hospital discharge, 0.3% (1/344) ongoing ≥24 months post ablation

Primary effectiveness
Freedom from AF at 24 Months (n=344)

Primary effectiveness at 24 months

2017 HRS/EHRA/ECAS/APHRS/SOLAECE consensus statement for the Management of Atrial Fibrillation Positive for Cryoballoon4

2017 HRS Consensus Statement

In the United States, our labeling supports the use of the cryoballoon in drug refractory, recurrent, symptomatic, paroxysmal, and persistent AF (episode duration less than 6 months) patients.



Packer, et al. Cryoballoon Ablation of Pulmonary Veins for Paroxysmal Atrial Fibrillation: First Results of the North American Arctic Front (STOP AF) Pivotal Trial. J Am Coll Cardiol. April 23, 2013;61(16):1713-1723.


January CT, et al. 2014 AHA/ACC/HRS Guideline for the Management of Patients With Atrial Fibrillation: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. Journal of the American College of Cardiology. December 2014; 64(21):e1-76.


Knight B, et al. Second Generation Cryoballoon Ablation in Paroxysmal Atrial Fibrillation Patients: 24 Month Safety and Efficacy from the STOP-AF Post Approval Study. Presented at HRS 2017 (Abstract).


Calkins H, et al. 2017 HRS/EHRA/ECAS/APHRS/SOLAECE Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation. Heart Rhythm. Published online May 12, 2017.

†Failed one or two of the following three antiarrhythmic drugs: flecainide, propafenone, sotalol.