​Maze surgery is used to correct an abnormal heart rhythm known as atrial fibrillation (abnormal heart rhythm originating from the atria) whereby multiple incisions are made in the left and right atrium (using radiofrequency ablation or cyroablation - freezing) to stop electrical impulses causing the atrial fibrillation or atrial flutter from spreading. This would help to reduce the risk of blood clots forming in the upper chambers of the heart and thus the risk of stroke. This procedure is usually performed concurrently with a surgery for valve or coronary artery disease.