Cryoballoon Ablation as Initial Therapy for Atrial Fibrillation
Atrial fibrillation (AF) is the maximum common cardiac arrhythmia, with an entire life risk exceeding 20% by 80 years of age. It is related to sizable morbidity associated with signs and symptoms, heart failure, and thromboembolism. Although AF is usually taken into consideration as non–life-threatening arrhythmia, it was associated with a 1.5- to 1.9-fold excess mortality after adjustment for pre-existing cardiovascular situations in the Framingham Heart Study. Despite those associations, antiarrhythmic drug (AAD) therapy with the aim of maintaining sinus rhythm has not improved outcomes in randomized trials.
In the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study, a strategy of heart rate management was equivalent to heart rhythm control in terms of all-reason mortality however superior in reducing hospitalizations.No studies have proven a reduction in stroke or heart failure while rhythm management is tried in patients with AF. If the patient has risk factors for thromboembolism, anticoagulation is maintained in either strategy. Therefore, the primary cause to pursue sinus rhythm in patients with AF is to improve their signs and symptoms and quality of life. An important variable in the assessment of efficacy for arrhythmia treatment is the selection of monitoring. The majority of studies for both the AAD and the radiofrequency ablation treatments evaluated patients with ECGs performed at specified intervals during follow-up visits. A minority of research used Holter or event monitors to evaluate arrhythmia recurrence between visits. The average achievement rate (usually described by authors as the disappearance of arrhythmia during the follow-up period) for all drug treatment groups becomes 52%. In comparison, the single-procedure success rate of ablation off AAD therapy was 57% (95% confidence interval, 50%–64%), the multiple technique success rates off AAD was 71% (95% confidence interval, 65%–77%), and the multiple technique success rates on AAD or with unknown AAD utilization become 77% (95% confidence interval, 73%–81%). This is a vital factor because it demonstrates the truth that catheter ablation does not necessarily obviate the long-term use of AADs. Many patients require continued AAD therapy after catheter ablation. From a safety standpoint, major complications of catheter ablation occurred in 4.9% of patients. Adverse events for AAD studies, despite the fact that more common (30%), have been much less severe.
Previously, catheter ablation was approved only for use in patients with AF who had failed antiarrhythmic drug therapy. The FDA granted a new indication to a cryoballoon ablation catheter that allows it to be used as a first-line treatment for atrial fibrillation even before the use of antiarrhythmic drugs. The decision was based on the results of the STOP AF First trial. Cryoballoon ablation is a preliminary therapy that has become superior to drug therapy for the prevention of atrial arrhythmia recurrence in patients with paroxysmal atrial fibrillation. Serious technique-associated adverse events have been uncommon.
