Reoperation for dysfunction of the Björk-Shiley mitral disc prosthesis: report of eight cases.

Of 193 patients with Björk-Shiley mitral valve prostheses, replacement was necessary in 8 (4.1%). The reasons for reoperation were: detachment (4), thrombosis (1), technical error (1), and late disc entrapment (2). Five of these patients died (62.5%), the death being directly related to the need for urgent operation because of low cardiac output. We recommend avoiding the use of the larger sized Björk-Shiley prostheses, since striking of the disc against the ventricle wall, probably consequent to postoperative decrease in heart size, may appear even 1 year after implantation of the prosthesis. An early diagnosis and early reoperation offer these patients a much more favorable prognosis.