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The aim of this study was to evaluate the long term fate of the cryopreserved mitral homograft focusing on structural valve deterioration (SVD).
Homograft replacement of the mitral valve was performed in 106 patients. The causes of mitral disease were: rheumatic disease (n=75), endocarditis (n=24) and others (n=7). There were 40 partial homografts and 66 total homografts.
Mean follow-up was 9.3 + 4.7 years (up to 17.8yrs). There were 5 early (< 3months) and 15 late deaths. There have been 5 early (<3 months) and 30 late reoperations. Five patients had endocarditis and 5 had ischemic/haemorrhagic event. As compared to baseline, follow-up echography showed progression of MR grade (from 0.4 to 1.3 p<0.001) with stenosis (elevated gradient: from 3.9 to 7.0 mmHg p<0.001 and decreased valve area: from 2.3 to 1.7 cm2 p<0.001). Freedom from SVD was 90%, 76% and 65% at 5 years, 10 years and 15 years respectively. SVD was more frequent in total homografts (p=0.018 vs partial homografts) and in case of pregnancy (p=0.016 vs no pregnancy). Stenosis related to SVD was more pronounced for age<40 years (p=0.03) and ring size ≤30 mm (p=0.002). Pathological analysis of the explanted homografts almost invariably showed dense fibrosis with calcification and no cellularity.
Mitral homografting could be accomplished with early echographic results similar to those of valve repair. SVD produced mixed stenosis with insufficiency and its incidence was comparable to that of bioprostheses SVD. An improvement in the preservation mode of valvular homografts is warranted.