Treatment of atrial fibrillation by creating linear lesions in patients undergoing heart surgery (mitral valve replacement or coronary bypass grafting) receives increasing interest. Conventional rhythm surgery require tremendous operative effort and increases the risks of perioperative complications. For that reason various alternative methods for creating linear lesion are under investigation. This paper discusses several techniques for creation of transmural lesions in open heart surgery, e.g. ultra sound ablation, high current DC shocks, laser ablation, cryoablation, radio frequency ablation, cooled radio frequency ablation, and microwave ablation.