How effective is cryoablation for atrial fibrillation during concomitant cardiac surgery?
Christian Fielder Camm1, Myura Nagendran, Phillip Yang Xiu
1New College, University of Oxford, Holywell Street, Oxford OX1 3BN, UK.
Insights
Cryoablation during heart surgery effectively treats atrial fibrillation (AF), restoring normal heart rhythm (SR). This procedure is superior to other methods, particularly for paroxysmal AF, with good safety outcomes.
Area of Science:
- Cardiothoracic Surgery
- Cardiac Electrophysiology
- Medical Devices
Background:
- Atrial fibrillation (AF) is a common arrhythmia requiring effective treatment.
- Concomitant surgical procedures offer an opportunity for AF ablation.
- Cryoablation is a minimally invasive technique used for cardiac ablation.
Purpose of the Study:
- To evaluate the effectiveness of cryoablative procedures during concomitant cardiac surgery for treating atrial fibrillation.
- To compare cryoablation with other treatment modalities for AF.
- To assess the safety and outcomes of concomitant cryoablation.
Main Methods:
- A systematic review of best evidence was conducted.
- Nine high-quality studies were identified from 291 papers.
- Data on patient groups, study types, and outcomes were tabulated and analyzed.
Main Results:
- Cryoablation during concomitant surgery significantly improved the rate of return to sinus rhythm (SR).
- Cryoablation was more effective than mitral valve surgery alone and catheter-based cryoablation at 12-month follow-up.
- Success rates were higher in patients with paroxysmal AF compared to permanent AF.
Conclusions:
- Concomitant cryoablation is a safe and effective treatment for AF.
- The procedure demonstrates significant success in converting patients to SR, with rates between 60% and 82% at 12 months.
- Further research with larger sample sizes and continuous monitoring is warranted to fully elucidate outcomes.
Abstract:
A best evidence topic in cardiothoracic surgery was written according to a structured protocol. The question addressed was whether performing cryoablative procedures during concomitant cardiac surgical procedures is effective for the treatment of atrial fibrillation (AF). Altogether 291 papers were found using the reported search, of which nine represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. All studies showed that cryoablation during concomitant surgery had a significant effect on return to sinus rhythm (SR) conversion rate. One study showed that cryoablation was significantly more effective than mitral valve surgery alone at a 12-month follow-up (73.3% vs. 42.9%, respectively, P=0.013). The use of a concomitant cryoablative procedure has also been shown to be far superior to subsequent catheter based cryoablation in returning patients to SR at a 12-month follow-up (82% and 55.2%, respectively, P<0.001). Another study showed a significant return to AF over a three-year period (91.8% and 84.1% at discharge and three years, respectively). Return to SR was significantly decreased in those patients suffering from permanent rather than paroxysmal AF (47% vs. 85%, P<0.001). Paucity of level 1 evidence was a major limitation to this analysis. All nine papers were either small randomised controlled trials or retrospective studies with small sample sizes (57-521) and varied follow-up regimens. Six of nine studies suggested that cryoablation is most successful in patients suffering from paroxysmal rather than permanent AF. A lack of 24-h monitoring in seven of nine studies prevented effective elucidation of the rate of paroxysmal AF following cryoablation. Only one study suggested an increased complication rate from cryoablation, however, none suggested any negative impact on mortality or morbidity. We conclude that cryoablation during concomitant surgery is a safe and acceptable intervention for the treatment of AF with an SR conversion rate of between 60% and 82% at 12-months postsurgery.
