Percutaneous aortic valve replacement: endovascular resection of human aortic valves in situ.

OBJECTIVE

Transluminal in vitro resection of severely calcified human aortic valves has already been successfully carried out by our group. The aim of this study was to analyze endovascular laser-assisted resection of human aortic valves in situ in 10 human cadavers.

MATERIAL AND METHODS

After anterolateral minithoracotomy, the aortic valve isolation chamber system was inserted into the descending aorta and pushed forward transluminally into the aortic position to generate a separate operation space between the subvalvular and the proximal ascending aortic area. After deployment and sealing of the chamber, stable function with a continuous chamber lavage of 1.58 L/min saline solution was established (8/10 cases). The endoscopically guided laser fiber was delivered via the right carotid artery. After fixation of a leaflet by a forceps catheter, the native leaflets were resected each by a thulium:YAG laser with 20-W power rating. Macropathology and micropathology of surrounding anatomic structures were analyzed.

RESULTS

The duration of transluminal positioning and deployment of the aortic valve isolation chamber took 7.3 +/- 5.8 minutes. Fluoroscopy confirmed sealed chambers. The resection was completed in all leaflets and took, on average, 6.0 +/- 3.5 minutes per leaflet. The aortic wall was moderately injured in 4 of 10 cases and the aortic annulus in two cases with one aortic wall perforation. The surrounding tissue, the coronary ostia, the mitral valve, and the left ventricular outflow tract remained unaffected.

CONCLUSION

This study demonstrates the feasibility of endovascular resection of human aortic valves in situ. This is a subsequent step toward complete percutaneous replacement (resection and implantation) of human aortic valves.