{'fraction_non_alphanumeric': 0.018494055482166448, 'fraction_numerical': 0.011448701012769706, 'mean_word_length': 4.916666666666667, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
[Experimental study of transcatheter aortic valve implantation assisted with snare to fix the delivery system].

OBJECTIVE
To evaluate the feasibility and effectiveness of transcatheter aortic valve implantation assisted with snare to fix the delivery system.


METHODS
This study was made in 5 healthy goats. After the abdomen was opened and the abdominal aorta was exposed, a stiff guide wire was advanced into the apex of the left ventricle through abdominal arterial puncture points. The delivery catheter equipped with valved stent was inserted into the descending aorta under fluoroscopy along the stiff guide wire. A minimal thoracic surgery approach was used to access the apex of the heart. A J-type guidewire and 5 F multifunction catheter were placed transapically and across the aortic valve down to the descending aorta. The snare was introduced through the 5 F catheter into the ascending aorta and was controlled to seize the head of stent delivery catheter. Then the delivery catheter was advanced into the left ventricle. The valved stent was positioned in the desired position under aortography and then the balloon was dilated and the valved stent was deployed into the aortic annulus assisted with snare to fix the catheter to prevent stent dispositions. Aortic angiography and echocardiography were performed to evaluate of valve performance post procedure.


RESULTS
The interventional procedure was completed successfully in all 5 goats. The mean aortic annulus diameter was (23.8 ± 2.6) mm, two valved stent of 23 mm diameter and three valved stent of 26 mm in diameter were implanted. The operation duration and X-ray exposure time were (112.3 ± 19.5) min and (16.8 ± 5.2) min, respectively. Immediate observation after procedure showed that the valved stents were in the desired position after implantation by angiography and echocardiography. No moderate to severe aortic regurgitation was observed. All goats were alive at 1 month post procedure.


CONCLUSIONS
The procedure of transcatheter implantation of a balloon-expandable valved stent into the aortic valve position of goats assisted with snare to fix the delivery catheter is feasible and effective. This procedure might be suitable also for patients with noncalcified aortic stenosis.