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

Nov 23, 2020
Font Size
A
A
A
Author/Summarized by Author:
Anthony A. Bavry, MD, MPH, FACC
Summary Reviewer:
Deepak L. Bhatt, MD, MPH, MBA, FACC
Trial Sponsor:
Medtronic
Date Presented:
08/29/2020
Date Published:
11/16/2020
Date Updated:
11/23/2020
Original Posted Date:
08/29/2020
References

Contribution To Literature:

The STOP AF First trial showed that a first-line strategy of cryoballoon ablation was superior to antiarrhythmic drug therapy at freedom from efficacy failure. 

Description:

The goal of the trial was to evaluate a first-line strategy of cryoballoon ablation compared with antiarrhythmic drug therapy among patients with paroxysmal atrial fibrillation.


Study Design

  • Randomized
  • Parallel

Eligible patients were randomized to pulmonary vein isolation with cryoablation (n = 104) versus antiarrhythmic drug therapy (n = 99).

  • Total number of enrollees: 225
  • Total number randomized: 203
  • Duration of follow-up: 12 months
  • Mean patient age: 60 years
  • Percentage female: 39%
  • Percentage with diabetes: 14%

Inclusion criteria:

  • Patients 18-80 years of age
  • Recurrent symptomatic paroxysmal atrial fibrillation

Exclusion criteria:

  • Previous treatment with antiarrhythmic drug for ≥7 days
  • Enlarged left atrial diameter (>5 cm)
  • Previous left atrial ablation or left atrial surgical procedure

Other salient features/characteristics:

  • Time from paroxysmal atrial fibrillation onset: 1 year
  • Electrical cardioversion within the last year: 18%

Principal Findings:

The primary efficacy outcome, freedom from efficacy failure at 12 months, occurred in 75% of the cryoballoon ablation group compared with 45% of the antiarrhythmic drug therapy group (p < 0.001). Efficacy failure was defined as acute procedural failure, any subsequent atrial fibrillation surgery or ablation procedure, or any of the following after the 90-day blanking period: atrial fibrillation/flutter/tachycardia, cardioversion, or antiarrhythmic drug therapy.

The primary safety outcome at 12 months occurred in 1.9% of the cryoballoon ablation group compared with a performance goal of <12% (p < 0.0001). The primary safety outcome was defined as transient ischemic attack (TIA), stroke, major bleeding, myocardial infarction, or vascular complication within 7 days; significant pericardial effusion within 30 days; or symptomatic pulmonary vein stenosis, atrial-esophageal fistula, or unresolved phrenic nerve injury within 12 months.

Secondary outcomes:

  • Atrial fibrillation/flutter/tachycardia after 90 days: 21 in the cryoballoon ablation group compared with 35 in the antiarrhythmic drug therapy group

Interpretation:

Among patients with paroxysmal atrial fibrillation, a first-line cryoballoon ablation strategy was superior to antiarrhythmic drug therapy. This strategy appeared to be safe with very few procedural-related adverse events. Current guidelines recommend catheter ablation after failure of antiarrhythmic drug therapy. To date, there is a paucity of data evaluating catheter ablation compared with antiarrhythmic drug therapy, with most of the studies examining radiofrequency ablation.


References:

Wazni OM, Dandamudi G, Sood N, et al., on behalf of the STOP-AF First Trial Investigators. Cryoballoon Ablation as Initial Therapy for Atrial Fibrillation. N Engl J Med 2020;Nov 16:[Epub ahead of print].

Presented by Dr. Oussama Wazni at the European Society of Cardiology Virtual Congress, August 29, 2020.

Clinical Topics: Arrhythmias and Clinical EP, Cardiac Surgery, Pericardial Disease, Implantable Devices, EP Basic Science, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias, Cardiac Surgery and Arrhythmias

Keywords: Anti-Arrhythmia Agents, Arrhythmias, Cardiac, Atrial Fibrillation, Atrial Flutter, Catheter Ablation, Cryosurgery, Electric Countershock, Ischemic Attack, Transient, Myocardial Infarction, Pericardial Effusion, Stroke, Tachycardia, Vascular Diseases, ESC20


< Back to Listings