The National Institute for Health and Clinical Excellence (NICE) has issued full guidance to the NHS in England, Wales, Scotland and Northern Ireland on microwave ablation for atrial fibrillation in association with other cardiac surgery.


Atrial fibrillation is the irregular and rapid beating of the upper two chambers of the heart (the atria). It may be classified as paroxysmal, persistent or permanent. Patients with atrial fibrillation may be asymptomatic or they may have symptoms including palpitations, dizziness and breathlessness. They also have an increased risk of stroke as a result of blood clots forming in the left atrium and then embolising to the brain. Although atrial fibrillation may occur in the absence of other heart disease, it is particularly common in patients with mitral valve disease.

Microwave ablation of the atria can be performed via a catheter introduced through a femoral vein but surgical microwave ablation for atrial fibrillation is typically carried out in patients undergoing concomitant open-heart surgery, including mitral valve replacement or repair. A microwave probe is used to create lines of conduction block by thermal damage rather than the incisions created in the traditional Cox maze surgery.

Coding and clinical classification codes for this guidance

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