Thorac Cardiovasc Surg 2012; 60(04): 290-292
DOI: 10.1055/s-0031-1299572
Short Communication
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Influence of Radiofrequency Energy on Polypropylene Sutures in Atrial Tissue

J. Bohn
1   Department of Cardiovascular Surgery, University Hospital Giessen and Marburg, Giessen, Germany
,
J. Gehron
1   Department of Cardiovascular Surgery, University Hospital Giessen and Marburg, Giessen, Germany
,
A. Dellmann
2   Institute for Pathology, City Hospital Braunschweig, Germany
,
A. Boening
1   Department of Cardiovascular Surgery, University Hospital Giessen and Marburg, Giessen, Germany
› Author Affiliations
Further Information

Publication History

19 May 2011

23 September 2011

Publication Date:
12 March 2012 (online)

Abstract

Objective Bipolar radiofrequency (RF) ablation is an established technique for the surgical treatment of atrial fibrillation. To create complete lesion sets, the bipolar device has to be partially inserted into the heart via a purse-string suture, which is subject to heat damage. We investigated the influence of RF ablation on the structure and function of polypropylene sutures.

Methods Six polypropylene sutures (4/0 Prolene; Ethicon, Norderstedt, Germany) were sutured ex vivo into atrial auricles from excised pig hearts. The tissue was treated by bipolar, saline-irrigated RF ablation (Cardioblate; Medtronic, Duesseldorf, Germany), until increase of tissue impedance pointed out a transmural lesion. After fixation in formaldehyde, the sutures were carefully removed and examined for ultrastructural damage using scanning electron microscopy, comparing them to sutures with intentional damage by instrumental grips. Tensile strength was tested applying a force velocity of 200 mm/min. Here, parts from the ablated zones were compared with parts from nonablated zones of the same suture.

Results We could not find ultrastructural damage in form of heat-induced changes in the helical polypropylene structure. Accordingly, the tensile strength of the ablated sutures (16.5 to 17.5 N) showed no difference to an untreated suture. In contrast, sutures damaged by instruments showed remarkable structural damage and could be torn without force.

Conclusion Bipolar, saline-irrigated RF ablation does not damage polypropylene sutures in spite of the heat applied to the tissue. Therefore, it is safe to create bipolar epi/endocardial lesions of the heart through polypropylene purse-string sutures.

 
  • References

  • 1 Cox JL, Jaquiss RD, Schuessler RB, Boineau JP. Modification of the maze procedure for atrial flutter and atrial fibrillation. II. Surgical technique of the maze III procedure. J Thorac Cardiovasc Surg 1995; 110 (2) 485-495
  • 2 Hamner CE, Potter Jr DD, Cho KR , et al. Irrigated radiofrequency ablation with transmurality feedback reliably produces Cox maze lesions in vivo. Ann Thorac Surg 2005; 80 (6) 2263-2270
  • 3 Deneke T, Khargi K, Grewe PH , et al. Left atrial versus bi-atrial Maze operation using intraoperatively cooled-tip radiofrequency ablation in patients undergoing open-heart surgery: safety and efficacy. J Am Coll Cardiol 2002; 39 (10) 1644-1650
  • 4 Ad N. The multi-purse string maze procedure: a new surgical technique to perform the full maze procedure without atriotomies. J Thorac Cardiovasc Surg 2007; 134 (3) 717-722
  • 5 Voeller RK, Zierer A, Schuessler RB, Damiano RJ. Performance of a novel dual-electrode bipolar radiofrequency ablation device. Innovations 2011; 6 (1) 17-22