Decellularized scaffolds represent a promising alternative for mitral valve (MV) replacement. This work developed and characterized a protocol for the decellularization of whole MVs. Porcine MVs were decellularized with 0.5% (w/v) SDS and 0.5% (w/v) SD and sterilized with 0.1% (v/v) PAA. Decellularized samples were seeded with human foreskin fibroblasts and human adipose-derived stem cells to investigate cellular repopulation and infiltration, and with human colony-forming endothelial cells to investigate collagen IV formation. Histology revealed an acellular scaffold with a generally conserved histoarchitecture, but collagen IV loss. Following decellularization, no significant changes were observed in the hydroxyproline content, but there was a significant reduction in the glycosaminoglycan content. SEM/TEM analysis confirmed cellular removal and loss of some extracellular matrix components. Collagen and elastin were generally preserved. The endothelial cells produced newly formed collagen IV on the non-cytotoxic scaffold. The protocol produced acellular scaffolds with generally preserved histoarchitecture, biochemistry, and biomechanics.

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Decellularization of ovine mitral valve results in a mitral valves scaffold with mechanical properties comparable with native tissue, and a graft surface, which can be repopulated by endothelial cells.

Background: In non-ST-elevation myocardial infarction (NSTEMI) there is no consensus regarding optimal time point for coronary artery bypass grafting (CABG). Recent findings suggest that long-term outcomes are improved in early-revascularized NSTEMI patients. However, it has been stated that early surgery is associated to increased operative risk. In this study, we wanted to elucidate if early CABG in non-ST-elevation acute coronary syndrome can be performed safely. Methods: We performed a monocentric-prospective observational study within a 2-year interval. A total of 217 consecutive patients (41 female, age 68.9±10.2, ES II 6.62±8.56) developed NSTEMI and underwent CABG. Patients were divided into two groups according to the time point of coronary artery bypass after symptom onset (group A: <72 h; group B: >72 h). Endpoints included 6-month mortality and incidence of MACE (death, stroke or re-infarction).Results: There were no differences regarding mortality between both groups (30 days: group A 2.4% vs. group B 3.7%; P=0.592; 6 months: 8.4% vs. 6.0%; P=0.487). Incidence of MACE in the 6-month followup was also similar in both groups (group A: 9.6% vs. 9.7%, P=0.982). Regression analysis revealed as independent risk factors for mortality in the entire cohort ES II OR 1.045 (95% CI: 1.004-1.088). ES II remained an independent prognostic factor in group A OR 1.043 (95% CI: 1.003-1.086) and group B OR 1.032 (95% CI: 1.001-1.063). Conclusions: Early revascularized patients showed a higher level of illness. However, results of early CABG were comparable to those following delayed revascularization. Moreover, EuroSCORE II was determined as independent risk factors for mortality.