Percutaneous aortic valve replacement: gross anatomy and histological findings after transapical and endoluminal resection of human aortic valves in situ.

OBJECTIVE Transluminal resection of the aortic valve was already successfully carried out by our group. The aim of this study was the analysis of the gross anatomy and the histology of the surrounding tissue after resection. METHODS Aortic valve resection was performed in postmortem human hearts (endoluminal (EL) n=9, transapical (TA) n=4). After deployment of the aortic valve isolation chamber, the leaflets were resected with a Thullium:YAG laser scalpel (cw, 20W). After resection, the hearts were analyzed to check for lesions caused by resectioning the associated tools. Therefore, gross anatomy and histological analysis were performed (H&E staining). RESULTS Lesions of the aortic annulus were seen in 3/9 (EL) (depth: 583+/-186 microm) and 2/4 (TA) (120 microm and one complete perforation), lesions of the aorta (ascending-arch-descending) in 4-9-0/9 (EL) and 0-0-0/4 (TA), lesions of the mitral valve in 0/9 (EL) and 0/4 (TA), lesions of the papillary muscle in 0/9 (EL) and 2/4 (TA) (depth: 400 microm and 450 microm), lesions of the endomyocardium in 0/9 (EL) and 4/4 (TA) (depth: 258+/-102 microm). The coronary ostia remained unaffected. CONCLUSIONS This study shows fewer severe lesions in the aorta after transapical antegrade access compared to the transluminal retrograde approach. Especially noteworthy is that the aortic arch remains unaffected by the transapical procedure. These data demonstrate the transapical approach as less hazardous.