Thorac Cardiovasc Surg 2004; 52(2): 124
DOI: 10.1055/s-2004-817945
Letter to the Editor

© Georg Thieme Verlag Stuttgart · New York

Letter to the Editor

M. Knaut1 , S. M. Tugtekin1 , K. Matschke1
  • 1Department of Cardiac Surgery, Heart Center Dresden University Hospital, Dresden, Germany
Further Information

Publication History

Received February 9, 2004

Publication Date:
22 April 2004 (online)

Doll et al. [[1]] report on esophagus perforation after left atrial radiofrequency ablation. Due to a relatively increased incidence of esophagus perforation leading to death the use of radiofrequency ablation was abandoned.

In our institution we initiated the use of microwave ablation for the surgical therapy of atrial fibrillation in 1998. Based on our experience with 265 patients with endocardial microwave ablation and a follow-up of up to four years we have not seen any indications of device-related complications, in particular we saw no clinical evidence of esophageal injury or perforation [[2]].

In-hospital mortality is 3 %. So far, no device-related mortality occurred. A potential explanation for the reduced risk of injury with microwave ablation is based on its action mechanism. The action mechanism of microwave ablation is based on 2.45 GHz electromagnetic radiation. The electromagnetic radiation induces rotation of the hydrogen atoms in the water molecule. This results in a fixed and stable coagulation necrosis without surface overheating or carbonization of the tissue. This fact explains that microwave-induced lesions applied with a definite power range have a restricted and local ablation effect. The induced scar forms a natural barrier against the further extension of the lesion. An additional protective factor in this context is the low H2O content in epicardial fat. This forms a natural barrier for the surrounding structures, in particular the esophagus, the vagus, and phrenic nerve.

Michael Knaut, MD Sems M. Tugtekin, MD Klaus Matschke, MD


MD Michael Knaut

Department of Cardiac Surgery · Heart Center Dresden University Hospital

Fetscherstraße 76

01307 Dresden


Email: [email protected]