[Unexpected early obstruction of a biological aortic valve prosthesis]

A 64 years old male was submitted to the surgical substitution of a deteriorated biological aortic valve prosthesis with a new Hancock II biological prosthesis. The implantation was not followed by an anticoagulation or antiaggregation therapy. Two months later he was checked at our Institution because he complained symptoms and developed echocardiographic indexes suggestive of an aortic prosthesis obstruction by a clot. Both symptoms and the echocardiographic indexes of prosthesis obstruction faded away after giving warfarin; they arose again when the anticoagulation therapy was stopped and was replaced by aspirin. The following permanent use of warfarin normalized both clinic and echocardiographic aspects. The present case report underlines the utility of early controls after a biological prosthesis, yet aortic, implantation, when it is not followed by an anticoagulant therapy, also in subjects free from thrombosis high risk factors.