Mitral Valve Repair Technique for the Left-Handed Surgeon

Introduction

Current data suggests that approximately less than 10% of surgeons are left-handed (1, 2). While the performance of various surgical procedures can be technically performed using either a left- or right-handed technique, left-handed surgeons have historically been trained to operate using a right-handed approach. Despite the availability of left-handed instruments, left-handed surgeons typically lack access to these instruments during surgical training, often receive little instruction on left-handed surgical technique, and are more prone to needle stick or other preventable injuries during surgery compared to right-handed surgeons. These challenges may be even more pronounced with the performance of cardiac surgery. Given the limited availability of resources available to instruct left-handed cardiac surgeons, herein the authors describe (and demonstrate in the accompanying video) various tips and techniques for mitral repair that can be utilized to facilitate the successful performance of a left-handed approach to mitral valve repair for degenerative mitral valve insufficiency.

Operative Technique

After standard preoperative preparation, including arterial and central venous monitoring, intraoperative transesophageal echocardiography is performed to carefully assess the mechanism of mitral regurgitation (MR). It is the authors’ practice to routinely repair ≥ 2+ MR. The key to successful mitral repair is exposure, which can be performed via either median sternotomy or through various minimally invasive techniques. In this example, after median sternotomy and pericardotomy, cardiopulmonary bypass is established using standard aortic and bicaval cannulation with vacuum-assisted venous drainage and a combination of both antegrade and retrograde cardioplegia. Next, traction is placed on the umbilical tape passed around the inferior vena cava, elevating the right side of the heart and facilitating surgical access to the left atrium and mitral valve. A left atriotomy is then performed beginning at the junction of the left atrium and right superior pulmonary vein, which is extended from under the superior vena cava to the inferior vena cava, exposing the entire mitral valve. The authors then utilize a Cosgrove self-retaining mitral retractor, and the operating table is rotated to the left away from the surgeon.

Direct inspection of the mitral valve is necessary to confirm intraoperative TEE findings and to completely assess valve pathology and the nature of MR. The example in this case is a Barlow’s valve with significant redundancy of the posterior leaflet tissue. Cold saline solution is directly infused into the left ventricle under pressure to demonstrate MV failure and regurgitation. It is necessary to then inspect the subvalvular apparatus. The valve annulus is then inspected and “true sized” in degenerative mitral disease. The authors rarely use < 36 mm annuloplasty ring in order to reduce the incidence of postoperative systolic anterior motion (SAM) of the mitral valve.

The authors then pre-place interrupted 2-0 braided (Ticron) sutures in the mitral annulus in preparation for annuloplasty. In general, either a left-handed or right-handed surgical technique can be utilized to accurately place the sutures. The critical step is accurate needle angles and to utilize traction on the leaflet to expose the mitral valve annulus. In addition, the authors’ technique is to ensure that the first annular stitch is placed above the anterolateral commissure to set up the remaining placement of the annular stitches. For the left-handed surgeon, the first 3-4 stitches are placed using a “backhand” technique with a transition to a “forehand” technique with subsequent stitches. Generally, 8-9 sutures are placed in total. The authors would emphasize that each stitch should incorporate enough annular tissue so as not to pull through the annulus.

Excess, redundant valve leaflet tissue is addressed next for degenerative mitral disease. It has become the authors’ practice to excise less leaflet tissue than we had previously. Excessive posterior leaflet tissue may be resected using either a triangular or quadrangular resection technique (the authors’ preference is generally for triangular resection). In the presence of excessive anterior leaflet redundancy, the authors prefer to perform mitral valve replacement. While other mitral repair techniques exist for excessive posterior leaflet tissue, the triangular resection with annuloplasty is preferred, as it is a predictable technique that is easy to teach trainees and residents, and it can be taught and mastered using both left-handed and right-handed techniques. The resection should not disrupt chordal attachments to remaining leaflet tissue. After the resection is complete, the mitral leaflet is repaired using 4-O Dacron suture in a continuous, running fashion. The repair is performed in two layers to minimize residual leakage. Also, the authors prefer not to use Prolene sutures for the repair so as to minimize leaflet trauma. A left-handed “forehand” technique can be utilized for this, making sure to complete a tension-free repair. Left-handed instruments may be utilized to facilitate surgical techniques.

An incomplete, semi-rigid annuloplasty ring is then appropriately sized to the surface area of the valve. Flexible rings are an alternative option; however, the authors prefer semi-rigid rings, as they maintain the valve annulus better. The previously placed mitral annulus sutures are then passed through the ring with appropriate spacing, and the ring is lowered into the annulus after moistening the sutures. The ring is generally placed beginning at the A1/P1 commissure around to the A3/P3 commissure. Annuloplasty sutures are sequentially tied down to restore mitral annulus anatomy and to maximize remodeling.

Pressurized cold saline infusion into the left ventricle is performed first after annuloplasty, and then followed by antegrade cardioplegia to test for residual MR or other clefts in the leaflets that require repair.

Standard de-airing maneuvers are performed as the atriotomy is closed. Further de-airing, release of the aortic cross clamp, and weaning from cardiopulmonary bypass is accomplished per routine. After weaning from bypass, TEE is used to confirm adequacy of the mitral repair. MR <1+ following repair is considered acceptable after appropriate volume loading of the left ventricle is achieved. MR ≥1+ after repair may require further repair techniques or mitral valve replacement.

References

1. Kim JY, Ali R, Cremers SL, Yun SC, Henderson BA. Incidence of intraoperative complications in cataract surgery performed by left-handed residents. Journal of cataract and refractive surgery. Jun 2009;35(6):1019-1025.
2. Makay O, Icoz G, Ersin S. Surgeon's view on the limitations of left-handedness during endoscopic surgery. Journal of laparoendoscopic & advanced surgical techniques. Part A. Apr 2008;18(2):217-221.