Obstruction of St Jude Medical valves in the aortic position: Significance of a combination of cineradiography and echocardiography

Abstract

Background: Obstruction of the St Jude Medical valve (St Jude Medical, Inc, St Paul, Minn) is a rare but serious complication. Methods: Cineradiographic and echocardiographic evaluations of aortic St Jude Medical valves were simultaneously performed on 54 patients, with no signs of prosthetic valve dysfunction late after surgery. Results: Although closing angles of the leaflets corresponded closely with the manufacturer data, restricted opening of the leaflets (opening angle ≥ 20°) was found in 16 (group D) of the 54 patients by means of cineradiography. The opening angles were equal to or less than 14° in the other 23 patients (group N) and between 15° and 19° in the remaining 15 (group M). Doppler-derived transprosthetic pressure gradients were significantly higher (P =.03) and the velocity index was significantly lower (P =.003) in group D than in group N. However, no significant differences were found in those values between group N and group M. Replacement of the aortic St Jude Medical valves was performed in 5 of the 16 patients, and the remaining 11 have been followed up because of relatively low pressure gradients. The cause of restricted leaflet movement was pannus formation without thrombosis in 4 patients and valve thrombosis with pannus formation in one. Conclusions: Reduced valve orifice area and restricted opening of the leaflets resulting from excess growth of pannus probably led to obstruction of the aortic St Jude Medical valves. A combination of cineradiography and echocardiography makes it possible to provide an accurate and detailed diagnosis of obstruction of the valve. (J Thorac Cardiovasc Surg 2000;120:142-7)