Sutureless replacement of aortic valves with St Jude Medical mechanical valve prostheses and Nitinol attachment rings: feasibility in long-term (90-day) pig experiments.
OBJECTIVE
Nitinol attachment rings (devices) used to attach mechanical aortic valve prostheses suturelessly were studied in long-term (90 days) pig experiments.


METHODS
The aortic valve was removed and replaced by a device around a St Jude Medical mechanical valve prosthesis in 10 surviving pigs. Supravalvular angiography was done at the end of the operation. No coumarin derivates were given.


RESULTS
No or minimal aortic regurgitation was confirmed in all surviving pigs at the end of the operation. Total follow-up was 846 days. In 4 pigs, follow-up was shorter than 90 days (28-75 days); the other 6 pigs did reach 90 days' survival or more. Repeat angiography in 4 pigs at the end of follow-up confirmed the unchanged position of the device at the aortic annulus, without aortic regurgitation. At autopsy, in all pigs the devices proved to be well grown in at the annulus, covered with endothelium, and sometimes tissue overgrowth related to not using coumarin derivates. There was no case of para-device leakage, migration, or embolization. No damage to surrounding anatomic structures or prosthetic valves was found.


CONCLUSIONS
Nitinol attachment rings can be used to replace the aortic valve suturelessly with St Jude Medical mechanical aortic valve prostheses, without para-device leakage, migration, or damage to the surrounding tissues, in long-term pig experiments during a follow-up of 90 days or more. Refraining from anticoagulation in pigs with mechanical valve prostheses can lead to tissue overgrowth of the valve prosthesis. Further studies are needed to determine long-term feasibility of this method in human beings.
Berreklouw
Eric
E
Catharina Hospital, Eindhoven, The Netherlands. berreklouw@gmail.com
Koene
Bart
B
De Somer
Filip
F
Bouchez
Stefaan
S
Chiers
Koen
K
Taeymans
Yves
Y
Van Nooten
Guido J
GJ
D000497:Alloys; D000818:Animals; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D001705:Bioprosthesis; D005240:Feasibility Studies; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000295:instrumentation*; D008422:Materials Testing; D023421:Models, Animal; D011474:Prosthesis Design; D011859:Radiography; D013536:Suture Techniques; D013552:Swine; D013997:Time Factors
D000497:Alloys; C013616:nitinol