HOMOGRAFT REPLACEMENT OF THE MITRAL-VALVE - GRAFT SELECTION, TECHNIQUE OF IMPLANTATION, AND RESULTS IN 43 PATIENTS

Because of experience gained in reconstructive mitral valve surgery, w e have reevaluated the implantation of cryopreserved homografts in the mitral position, Forty-three patients, aged 11 to 69 years (mean 34 y ears), underwent mitral valve replacement with cryopreserved mitral ho mografts, The indications for the procedure were acute endocarditis (n = 14), rheumatic stenosis (n = 26), systemic lupus endocarditis (n = 2), and marasmic endocarditis (n = 1), All homografts were obtained fr om hearts explanted in the course of transplantation and were cryopres erved at -160 degrees C in 10% dimethyl sulfoxide solution without ant ibiotics. Appropriate sizing was based on morphologic study of the hom ografts and preoperative echocardiographic assessment of the recipient valve, In 82 homografts analyzed, the height of the anterior leaflet was 25 +/- 3 mm and the distance from the anulus to the apex of the an terior papillary muscle was 21 +/- 3 mm, The morphologic features of t he papillary muscles were classified according to four types of increa sing complexity, Nine valves with complex (type IV) papillary muscle a bnormalities were discarded, Echocardiographic measurements of the val ve were matched with those of the homograft identification cards and a slightly larger homograft was selected (measurements + 3 mm). Partial homograft replacement was done in case of a localized lesion (abscess or calcification) (n = 21). Total homograft replacement was undertake n in the presence of diffuse lesions (n = 22), Two hospital deaths occ urred as a result of poor cardiac output. One patient required reopera tion on the tenth postoperative day after a dehiscence on the valvular suture line, After a mean follow-up of 14 months, there has been one late death caused by a bronchial neoplasm and one reoperation for resi dual stenosis (partial replacement), The remaining patients were in ei ther New York Heart Association class I (II = 25) or II (n = 13), Thir ty-three patients were in sinus rhythm. Follow-up echocardiography has revealed no mitral regurgitation (12 = 20), minimal mitral regurgitat ion (n = 13), and mild mitral regurgitation (n = 5), Surface valve are a has been calculated at 2.5 +/- 0.4 cm(2) in partial homograft recons truction and 2.7 +/- 0.3 cm(2) in total homograft replacement, with a transvalvular gradient of 3 +/- 4 mm Hg, Conclusion: In a selected gro up of patients, the use of mitral homografts significantly extended th e present limitations of reparative surgery of the mitral valve.