Totally endoscopic mitral valve repair employing the ten-loop technique for Barlow’s disease

BRIEF EXPLANATION

A 76-year-old female [height: 148 cm, weight: 46 kg, body surface area (BSA): 1.37 m²] underwent thrombectomy 4 months earlier for a cardiogenic cerebral embolism secondary to paroxysmal atrial fibrillation. Preoperative transthoracic echocardiography revealed severe mitral regurgitation due to Barlow’s disease [Video 1]. Transesophageal echocardiography (TEE) demonstrated bileaflet prolapse and annular dilatation, and surgical intervention was planned. To minimize the invasiveness in this elderly female patient and avoid median sternotomy, a totally endoscopic mitral valve repair was performed [Video 2]. To shorten the duration of cardiac arrest, five pre-formed loops of varying lengths are prepared in advance using expanded polytetrafluoroethylene (ePTFE; CV-4) [Video 3]. The main incision was a 30 mm skin incision at the right fifth intercostal space, where an extra extra small (XXS)-sized wound retractor was placed. Additional ports were inserted in the right second and third intercostal spaces, resulting in a 3-port setup. All surgical procedures were performed endoscopically without direct vision. Without leaflet resection, five artificial chordae with loops made of ePTFE (CV-4) were anchored to both the anterior and posterior papillary muscles, and ten loops were fixed to the mitral leaflets using CV-5 sutures. In addition, cryoablation for left atrial maze and left atrial appendage closure were performed to address paroxysmal atrial fibrillation. The operative time was 272 min, and the aortic cross-clamp time was 161 min. The patient was extubated on the day of surgery, drains and central venous catheter were removed on postoperative day (POD) 1, and she was discharged on POD 6 [Figure 1]. Postoperative TEE revealed no mitral regurgitation[Video 4]. Mitral valve repair for Barlow’s disease is technically demanding and associated with a high risk of recurrence^[1]. The use of multiple artificial chordae enables a repair strategy that can reduce the risk of recurrent regurgitation in Barlow’s disease^[2]. The loop technique enables the implantation of multiple artificial chordae^[3,4]. At our institution, we routinely implant ten artificial chordae in mitral valve repair for Barlow's disease, regardless of whether leaflet resection is performed^[5]. The length of the loops was determined based on measurements of the anterior and posterior leaflet lengths obtained from preoperative cardiac computed tomography (CT) and TEE, referring to the distance from the papillary muscles that would achieve an appropriate coaptation length of 5 to 10 mm. In most cases, ten artificial chordae are implanted - four longer loops attached to the anterior leaflet and six shorter loops attached to the commissural and posterior leaflets. In general, the chordae of the anterior leaflet are longer than those of the posterior leaflet, and the artificial chordae for the anterior leaflet are typically 3-5 mm longer. The ten-loops technique enabled safe and effective mitral valve repair through a totally endoscopic approach.

Figure 1. The figure shows the surgical wounds 30 days postoperatively. Ports were placed in the second and third intercostal spaces, and a 30-mm main incision was positioned in the sixth intercostal space along the inframammary line.