Radiofrequency catheter ablation for atrial fibrillation (interventional procedure consultation document)
NATIONAL INSTITUTE FOR HEALTH AND CLINICAL EXCELLENCE
Interventional Procedure Consultation Document
Percutaneous radiofrequency catheter ablation for atrial fibrillation
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The National Institute for Health and Clinical Excellence is examining percutaneous radiofrequency catheter ablation for atrial fibrillation and will publish guidance on its safety and efficacy to the NHS in England, Wales and Scotland. The Institute's Interventional Procedures Advisory Committee has considered the available evidence and the views of Specialist Advisors, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about percutaneous radiofrequency catheter ablation for atrial fibrillation.
Note that this document is not the Institute's formal guidance on this procedure. The recommendations are provisional and may change after consultation. The process that the Institute will follow after the consultation period ends is as follows.
For further details, see the Interventional Procedures Programme manual, which is available from the Institute's website (www.nice.org.uk/ipprogrammemanual). Closing date for comments: 31 January 2006 |
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Note that this document is not the Institute's guidance on this procedure. The recommendations are provisional and may change after consultation. |
| 1 | Provisional recommendations |
| 1.1 |
Current evidence on the safety and efficacy of percutaneous radiofrequency catheter ablation for atrial fibrillation appears adequate to support the use of this procedure in appropriately selected patients (see 2.1.4) provided that normal arrangements are in place for audit and clinical governance. |
| 1.2 | Clinicians should ensure that patients fully understand the potential complications, the likelihood of success and the risk of recurrent atrial fibrillation associated with this procedure. In addition, use of the Institute's Information for the public is recommended (available from www.nice.org.uk/IPGxxxpublicinfo). |
| 1.3 | This procedure should only be performed in specialist units where there are arrangements for cardiac surgical support in the event of complications. |
| 1.4 | This procedure should only be performed by cardiologists with extensive experience of other types of ablation procedures. |
| 1.5 |
The Department of Health runs the UK Central Cardiac Audit Database (UKCCAD), and clinicians are encouraged to enter all patients undergoing percutaneous radiofrequency catheter ablation for atrial fibrillation onto this database (www.ccad.org.uk). |
| 2 | The procedure |
| 2.1 | Indications |
| 2.1.1 | Atrial fibrillation is the irregular and rapid beating of the upper two chambers of the heart (the atria). Patients with atrial fibrillation may be asymptomatic or may have symptoms including palpitations, dizziness, breathlessness and fatigue. They have an increased risk of stroke as a result of blood clots forming in the left atrium and then embolising to the brain. |
| 2.1.2 | Atrial fibrillation usually occurs in the absence of structural heart disease. However, if structural heart disease is present, it is most commonly mitral stenosis. |
| 2.1.3 | Conservative treatments include medications to control the heart rhythm and rate, electrical cardioversion and anticoagulants to prevent blood clots forming. Surgery for atrial fibrillation is usually performed at the same time as open heart surgery for another indication, such as mitral valve disease. The conventional surgical approach, known as the Cox maze procedure, involves making multiple, strategically placed incisions in both atria to isolate and stop the abnormal electrical impulses. This is usually performed at the same time as open heart surgery for another indication, such as mitral valve disease. |
| 2.1.4 |
Alternative methods of creating lesions in the atria by ablation have been developed, using energy sources such as radiofrequency, microwave energy, cryotherapy and ultrasound. Radiofrequency ablation is a treatment option for symptomatic patients with atrial fibrillation refractory to medical therapy or where medical therapy is contraindicated because of comorbidities or intolerance. |
| 2.2 | Outline of the procedure |
| 2.2.1 | Radiofrequency catheter ablation is a minimally invasive procedure that is usually carried out under sedation. A catheter is inserted into the femoral vein and advanced into the heart, using X-ray fluoroscopy to ensure correct positioning. An attachment at the tip of the catheter sends out radiofrequency energy, producing heat that damages the targeted area of the conduction pathway. Electrophysiological testing is done before the procedure to identify and map the source of the abnormal electrical signals. Advanced imaging and mapping techniques that do not require fluoroscopy have also been developed for use in this procedure. |
| 2.2.2 |
Several different strategies may be used, including linear ablation in the left or right atrium and focal pulmonary vein ablation. |
| 2.3 | Efficacy |
| 2.3.1 |
In a small randomised controlled trial, frequency of symptoms decreased from mean 42.8 attacks per month at baseline to 0.9 attacks per month at 1 year in 14 patients after radiofrequency ablation (p < 0.001). |
| 2.3.2 | In a non-randomised comparative study of 1171 patients, 78% of patients treated with radiofrequency catheter ablation were estimated to be free of atrial fibrillation at 3 years, compared with 37% of patients treated with medication (p < 0.001). Patients receiving radiofrequency catheter ablation had a 54% reduction in risk of death compared with those receiving medication (p < 0.001). |
| 2.3.3 | A large survey reported that 76% (6644/8745) of treated patients had resolution of symptoms of atrial fibrillation after a median follow-up of 12 months (this proportion ranged from 22% to 91% among different centres). For more details, refer to the sources of evidence (see Appendix). |
| 2.3.4 |
The Specialist Advisors noted the lack of long-term data. |
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| 2.4 | Safety |
| 2.4.1 | A complication rate of 6% (524/8745) was reported in the survey of 8745 patients who had undergone catheter ablation for atrial fibrillation. The most significant complications reported in this study were four early deaths (0.05%), 20 strokes (0.28%), 47 transient ischaemic attacks (0.66%), 117 cases of pulmonary vein stenosis (1%),107 episodes of cardiac tamponade (1%) and 37 cases of arteriovenous fistula (0.4%). |
| 2.4.2 | In two comparative studies of 1171 and 30 patients respectively, complications specific to radiofrequency catheter ablation included cardiac tamponade in less than 1% (4/589) of patients, stroke in 7% (1/14) and groin haematoma in 7% (1/14). |
| 2.4.3 |
Two of the studies also reported that 2% and 4% of patients respectively (12/589 and 340/8745) developed atypical atrial flutter of new onset after undergoing catheter ablation. For more details, refer to the sources of evidence (see Appendix). |
| 2.4.4 | The Specialist Advisors listed the potential adverse events as stroke, cardiac tamponade, atrial fistula and pulmonary vein stenosis. |
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| 3 | Further information |
| 3.1 | The Institute has issued guidance on radiofrequency ablation, microwave ablation, and cryoablation for atrial fibrillation in association with other cardiac surgery (available from www.nice.org.uk/IPG121, www.nice.org.uk/IPG122 and www.nice.org.uk/IPG123 respectively). |
| 3.2 |
The Institute is also developing Interventional Procedures guidance on high-intensity focused ultrasound for atrial fibrillation as an associated procedure with other cardiac surgery (www.nice.org.uk/ip_312) and a clinical guideline on atrial fibrillation (www.nice.org.uk/guidelines.inprogress.atrialfibrillation). |
Bruce Campbell
Chairman, Interventional Procedures Advisory Committee
January 2006
| Appendix: | Sources of evidence |
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The following document, which summarises the evidence, was considered by the Interventional Procedures Advisory Committee when making its provisional recommendations.
Available from: www.nice.org.uk/ip300overview | |
This page was last updated: 04 February 2011