Vertical Folding As A Functional Alternative To Triangular Resection In Mitral Valve Repair Via Minithoracotomy Approach. Feasibility And Drawbacks.
Kazuma Okamoto, Hiroto Kitahara, Mikihiko Kudo, Akihiro Yoshitake, Takashi Hachiya, Ryo Aeba, Shinji kawaguchi, Hirofumi Haida, Akinori Hirano, Kanako Hayashi, Yu Inaba, Hideyuki Shimizu
Although a triangular resection and suture technique is a golden standard of posterior leaflet prolapse in mitral valve repair, precise resection of an optimal leaflet area is not always easy, especially in minimally invasive approach. A vertical folding technique has potential advantages that it is feasible and unfavorable folding can be canceled only with cutting sutures. As a functional alternative of triangular resection, a short-term result of a vertical folding technique for posterior leaflet in mitral valve repair via minithoracotomy was verified.
The result of a vertical folding technique without leaflet resection, used in consecutive 17 cases (mean age 56.5 years, female 1) between July 2013 and November 2014, was verified retrospectively. Endoscopic assisted minithoracotomy approach was applied in all cases. Tricuspid annuloplasty was added in a case. Cardiopulmonary bypass (CPB) was established with femoral artery, femoral vein, and internal jugular vein cannulation. Cardiac arrest was afforded by ante-grade cold cardioplegia under direct cross clamping with a Chitwood clamp. A prolapsed posterior leaflet was folded vertically with 4 to 5 interrupted 5-0 Prolene sutures. To decrease the height of the folded posterior leaflet, neo-chordal creations using Loop-in-Loop technique were added. Mitral annuloplasty was added with full ring in all cases.
Mean CPB time was 221.9 ± 47.8 minutes and mean aortic cross-clamp time was 148.1 ± 34.7 minutes. There was no mortality. The number of neo-chordae was 1.5 ± 1.4 (0 - 4). Tree types of mitral annuloplasty rings (CG Future ring 11, Physio II 5, MEMO 3D 1) were used and their mean size was 31.2 ± 2.7 (28 - 36). In follow-up (4 - 709 days), mitral valve regurgitation was mild or less in all cases. Mean pressure gradient of the mitral valve was 3.2 ± 1.5 (1.1 - 6.7) mmHg and more than 5.0 mmHg in two cases. Both cases were asymptomatic. In one of them, edge-to-edge of A2 and P2 was added.
A vertical folding technique was a feasible alternative to the resection and suture technique in minithoracotomy approach. Although it was very good technique in terms of control of mitral regurgitation, there was a potential risk of postoperative mitral stenosis. Further technical improvement to preserve mobility of the posterior leaflet was thought to be important to avoid mitral stenosis.