An automated coring and apical connector insertion device facilitates aortic valve bypass (apicoaortic conduit) surgery: preclinical experience in a chronic ovine model.

摘要

Aortic valve bypass (AVB, apicoaortic conduit) surgery is an alternative treatment for high-risk patients with aortic stenosis (AS). An automated coring and connector insertion device designed to simplify the apical AVB anastomosis has been developed. The applicator consists of a toroidal shaft-mounted balloon, an integrated circular coring knife, and a stented apical connector supporting a Dacron graft. In this way, apical myocardial coring, connector insertion and core removal may be automated.AVB was performed without cardiopulmonary bypass in eight sheep. A conduit containing a porcine valve was anastomosed to the descending aorta using a partial occlusion clamp. The applicator was used to insert the apical connector, and the connector and conduit were joined with a quick-connector. The descending aorta was occluded proximal to the distal anastomosis to simulate AS. Gradients across the conduit were measured after implantation, and one month later at sacrifice.All AVB implants were performed successfully. The median blood loss was 50 ml (IQR: 13- 98 ml). The median connector implantation time was 29 s, and the peak gradients across the conduit early and at 30 days after AVB were 5.2 +/- 2.6 mmHg and 2.7 +/- 1.4 mmHg, respectively. One animal died of hemothorax at 24 h after surgery, but all remaining animals survived and gained weight. Gross and histopathologic assessments demonstrated widely patent conduits and normal brain histology in all animals.The applicator facilitated the safe and expeditious performance of AVB surgery. The clinical use of this device will improve the safety and increase the adoption of this beating-heart therapy for AS.