Recellularized bovine pericardium with autologous mesenchymal stem cells reduces immune activation.

INTRODUCTION: Current bioprosthetic heart valve replacement options are limited by structural valvular deterioration (SVD) due to an immune response to the xenogenic scaffold. Autologous mesenchymal stem cell (MSC) recellularization is a method of concealing xenogenic scaffolds, preventing recipient immune recognition of xenogenic tissue heart valves, and potentially leading to reduction in SVD incidence. The purpose of this study is to examine the effects of autologous MSC recellularized tissue on the immune response of human whole blood to bovine pericardium (BP). We hypothesized that autologous MSC recellularization of BP will result in reduced pro-inflammatory cytokine production equivalent to autologous human pericardium. METHODS: Bone marrow, human pericardium, and whole blood were collected from adult patients undergoing elective cardiac surgery. Decellularized BP underwent recellularization with autologous MSCs, followed by co-incubation with autologous whole blood. Immunohistochemical, microscopic, and quantitative immune analysis approaches were used. RESULTS: We demonstrated that native BP, exposed to human whole blood, results in significant TNF-α and IL1ß production. When decellularized BP is recellularized with autologous MSCs and exposed to whole blood, there is a significant reduction in TNF-α and IL1ß production. Importantly, recellularized BP exposed to whole blood had similar production of TNF-α and IL1ß when compared to autologous human pericardium exposed to human whole blood. CONCLUSION: Our results suggest that preventing initial immune activation with autologous MSC recellularization may be an effective approach to decrease the recipient immune response, preventing recipient immune recognition of xenogeneic tissue engineered heart valves, and potentially leading to reduction in SVD incidence.

Review of the differences in outcomes between males and females after revascularization.

PURPOSE OF REVIEW: This review aims to compare outcomes of males and females undergoing coronary artery bypass grafting (CABG), percutaneous coronary intervention (PCI), off-pump CABG (OPCAB), minimally invasive direct CABG (MIDCAB), and robotic total endoscopic CABG (TECAB). RECENT FINDINGS: Females demonstrated increased rates of morbidity and mortality post PCI and CABG. In studies that performed risk adjustments, these differences were reduced. Although inferior outcomes were observed for females in some measures, generally outcomes between males and females were comparable post OPCAB, MIDCAB, and TECAB. SUMMARY: Previous literature has demonstrated that females undergoing coronary revascularization experience inferior postoperative outcomes when compared to their male counterparts. The discrepancies between males and females narrow, but do not disappear when preoperative risks are accounted for and when considering minimally invasive approaches such as MIDCAB, OPCAB, and TECAB. Minimally invasive cardiac surgery has demonstrated numerous benefits with reduced morbidity, mortality, and shorter recovery times. In patients with increased comorbidities, minimally invasive approaches confer a greater advantage. As females often fall within this category, it is paramount that the diagnosis and referral process be optimized to account for preoperative differences to provide the most beneficial approach if the disparity between the sexes is to be addressed.