Author/Editor		Gregorič, ID; Tamez, D; Karabulut, MN; Cervera, R; Conger, J; Eya, K; Lapeyre, D; Radovancevic, B; Frazier, OH
Title		Aortic valve implantation in the calf: a successful approach using Heartport cannulation and minimally invasive techniques
Type		članek
Source		J Heart Valve Dis
Vol. and No.		Letnik 10, št. 5
Publication year		2001
Volume		str. 675-80
Language		eng
Abstract		Background and aim of the study: Aortic valve replacement (AVR) for mechanical prosthetic valvular testing has not been performed in calves because of anatomic difficulties, and sheep have traditionally been used in this situation. Hemodynamically, however, the calf constitutes an excellent model due to vigorous myocardial contractility, high stroke volumes and high cardiac output, and so has been used for preclinical evaluation of mechanical assist devices and mechanical valves in the mitral and tricuspid positions, which can be approached with relative surgical ease. Recently, a juvenile bovine model has been used to test a newly developed mechanical valve in the aortic position. Methods: Ten calves (body weight 91+/-11 kg) underwent AVR with a 21-mm mechanical prosthesis via a small left intercostal thoracotomy with the aid of a Heartport cannulation device. A standard cardiopulmonary bypass (CPB) circuit was used. To circumvent the short bovine ascending aorta and to gain additional space to perform the aortotomy, two aortic cannulas were inserted for arterial-systemic perfusion. Nine calves each received a 21-mm experimental trileaflet aortic central flow valve prosthesis, and one calf received a 21-mm St. Jude Medical prosthesis. Results: Mean CPB duration was 154.2+/-44.4 min, and mean ischemic time 80.1+/-15.9 min. Mean study duration was 42.6+/-53.7 days. Three calves were killed prematurely: two on days 2 and 7 due to complications arising from inadvertent entrapment of the right coronary artery ostium by a suture, and one on day 0 due to an accidental overdose of magnesium. Three calves, all of which had a first-version test valve, were killed electively due to valve malfunction secondary to early valvular thrombosis. Four animals (three with the final version valve and one with a standard valve as a control) survived until killed electively (range: 33-172 days). (Abstract truncated at 2000 characters)
Descriptors		ANIMALS AORTIC VALVE BODY WEIGHT CARDIOPULMONARY BYPASS CATTLE HEART CATHETERIZATION HEART VALVE DISEASES MODELS, CARDIOVASCULAR POSTOPERATIVE COMPLICATIONS PROSTHESIS DESIGN TIME FACTORS TREATMENT OUTCOME