Cardiac ablation and mapping 

STOP Persistent AF trial

A study to evaluate the safety and effectiveness of the Medtronic Arctic Front™ cryoablation system for treating drug-refractory, symptomatic, persistent atrial fibrillation.

Female healthcare professional wearing white coat and holding clipboard in a room with sink and medical supplies behind her

Study purpose and design

The STOP Persistent AF trial is the first and largest, prospective, multicenter, single-arm study with prespecified performance goals to assess the safety and efficacy of pulmonary vein isolation (PVI) using the Medtronic Arctic Front Advance™ cryoballoon for patients with drug-refractory, symptomatic, persistent AF. The trial included 165 patients treated at 25 sites across the United States, Canada, and Japan.1

Arctic Front cryoballoon encircled on a gray background

Key findings


Primary effectiveness endpoint met

Primary efficacy endpoint of 54.8% exceeded prespecified performance goal (P < 0.001).


Primary safety endpoint met

Primary safety endpoint rate of 0.6% was below prespecified performance goal (P = 0.002). Only one primary safety event occurred and was unrelated to study device. 

121 minutes

Efficiency outcomes

Short and predictable procedure times of 121 ± 46 minutes

Quality-of-life outcomes

86.8% secondary endpoint assessments of quality of life demonstrated significant improvements by 12 months post-ablation (P < 0.001) with a high rate of freedom from repeat ablation (86.8%).

Graph showing the mental and physical health improvements 12 months after an Arctic Front cryoballoon procedure
Graph showing the symptoms reported by patients twelve months after an Arctic Front cryoballoon procedure

Watch the scientific exchange video.

Learn more about the Impact of Arctic Front™ Cryoballoon Ablation for the Treatment of Persistent Atrial Fibrillation featuring a discussion of the clinical evidence supporting PVI for persistent AF and STOP Persistent AF trial results.

  • Dr. Hugh Calkins
  • Dr. Vivek Reddy
  • Dr. Wilber Su 

Log in to Medtronic Academy to view the video.

Video thumbnail

Endpoint definitions

Primary efficacy endpoint

Success at 12 months > 40% performance goal

  • Acute procedural success (cryoballoon PVI only)
  • Freedom from AF/AT/AFL ≥ 30 sec after 90-day blanking
  • No class I or III AAD dose initiation/increase after blanking

Primary safety endpoint

Safety event rate < 13% performance goal

  • Within 7 days: death, transient ischemic attack, cerebrovascular accident, major bleeding that requires transfusion, myocardial infarction, cardiac perforation, tamponade, or pericardial effusion
  • Within 12 months: PV stenosis or AE fistula
  • At 12 months: unresolved PNI

Study population

Key inclusion criteria

  • Symptomatic, persistent AF defined as a continuous, sustained episode lasting longer than 7 days but ≤ 6 months
  • Failure or intolerance of at least one AAD
  • At least 18 years of age

Key exclusion criteria

  • Prior left atrial ablation or surgery
  • Stroke/transient ischemic attack within 6 months of enrollment
  • Left ventricular ejection fraction ≤ 35%
  • Left atrial diameter > 5.0 cm

Study recurrence monitoring



Blanking period 6W

3 months

6 months

12 months

Weekly and symptomatic tele-ECG monitoring    

 ➜  ➜

Telephone follow-up





In-office 12-lead ECG



In-office 24-hour Holter




Quality-of-life survey



Educational resources on
Medtronic Academy

Access detailed product information, including spec sheets, videos, and presentations.



Su WW, Reddy VY, Bhasin K, et al. Cryoballoon ablation of pulmonary veins for persistent atrial fibrillation: results from the multicenter STOP Persistent AF trial. Heart Rhythm. 2020;17(11):1841–1847.