Session S41.3

Adjustment of Artificial Chordae to the Mitral Valve with Advanced Tactile Technique

EU Braun*, B Voss, H Mayer, A Knoll,
R Bauernschmitt, R Lange

German Heart Center Munich
Munich, Germany

The precise determination of the length of artificial chordae on the mitral valve is a challenge especially for the minimally invasive working heart surgeon. Methods to secure the correct length of the artificial chordae have been presented in the past either with the pean clamp or the more convenient but more breakable method with the hemoclip. Here the hemoclip-method is tested in an ameliorated tactile technique to advance the security for the patient.
A total of 70 ePTFE (expanded polytetrafluoroethylene, Gore Tex®) 4-0 sutures has been tested in 7 groups. One surgeon tied 10 knots to fix the artificial chordae by bare hand, with surgical knot pusher device, fixed by pean or hemoclip, each with patch or without patch. The modification in this setup was an either absolutely strong or an only surgical contact pressure of the hemoclips. The knotted sutures have been fixed to a robot (Mitsubishi) with two force sensor arms testing the break force of each suture.
The sutures knotted by hand and knotted by knot-pusher don´t show any difference in breaking force. The pean clamp does not harm the suture significantly. Patches do not influence the stability of these sutures. The strongly clipped hemoclip weakens the suture significantly. Using the clip with tactile surgical feedback the suture is unbroken. This technique can be used for artificial chordae-procedure. In future a clip gripper measuring the contact pressure online and evaluating a defined force feedback has to be designed for safety reasons for the patients.

(Abstract Control Number: 237)