Objective: To improve the outcome of percutaneous valve replacement in aortic stenosis, endovascular resection of calcified aortic valves will be necessary. In this study different sealing methods were evaluated and a laser-assisted resection of sclerotic human aortic valves was performed in human preparations. The focus of this research was feasibility and mechanical functionality in human anatomy.
Material and Methods: The aortic valve isolation chamber (AVIC) is a catheter based system to seal the aortic valve during resection, and was installed antegrade and retrograde. Firstly, AVIC was inserted antegrade via the cardiac apex in human post mortem models (n=2), and secondly in porcine in vivo models on ECC (n=5). Endoscopic inspection of the valve was recorded. Consecutive valve resection in human preparations (n=8) was performed retrograde by an endoscopic guided Thulium:YAG-laser (2.01μm, 20W, continuous, ITL Lasergeräte Luebeck, Germany). AVIC was installed via a port system through the descending aorta [Fig. 1a]. Micro- and macropathology were performed.
Results: AVIC transapical deployment in human models took 3min and 4min and in porcine models 2.2±1.3min. From the descending aorta, deployment took 9.3±5.5min. Fluoroscopy and macroscopy showed sealed chambers [Fig. 1b]. The endovascular resection took 20.4±6.5min [Fig.1c]. The resected leaflets were removed via AVIC. Microscopic and histological analysis demonstrated no significant damages of the surrounding tissue.
Conclusion: This study demonstrates the feasibility of transapical and retrograde endovascular sealing in vivo and in vitro with consecutive resection of sclerotic aortic valves in human preparations.