Human Saphenous Vein Endothelial Cell Isolation and Exposure to Controlled Levels of Shear Stress and Stretch.

Coronary artery bypass graft (CABG) surgery is a procedure to revascularize ischemic myocardium. Saphenous vein remains used as a CABG conduit despite the reduced long-term patency compared to arterial conduits. The abrupt increase of hemodynamic stress associated with the graft arterialization results in vascular damage, especially the endothelium, that may influence the low patency of the saphenous vein graft (SVG). Here, we describe the isolation, characterization, and expansion of human saphenous vein endothelial cells (hSVECs). Cells isolated by collagenase digestion display the typical cobblestone morphology and express endothelial cell markers CD31 and VE-cadherin. To assess the mechanical stress influence, protocols were used in this study to investigate the two main physical stimuli, shear stress and stretch, on arterialized SVGs. hSVECs are cultured in a parallel plate flow chamber to produce shear stress, showing alignment in the direction of the flow and increased expression of KLF2, KLF4, and NOS3. hSVECs can also be cultured in a silicon membrane that allows controlled cellular stretch mimicking venous (low) and arterial (high) stretch. Endothelial cells' F-actin pattern and nitric oxide (NO) secretion are modulated accordingly by the arterial stretch. In summary, we present a detailed method to isolate hSVECs to study the influence of hemodynamic mechanical stress on an endothelial phenotype.

MiRNA-30d and miR-770-5p as potential clinical risk predictors of Vasoplegic Syndrome in Patients undergoing on-pump coronary artery bypass grafting.

The aims of this study were to perform pre-surgery miRNA profiling of patients who develop Vasoplegic syndrome (VS) after coronary artery bypass grafting (CABG) and identify those miRNAs that could be used as VS prognostic tools and biomarkers. The levels of 754 microRNAs (miRNAs) were measured in whole blood samples from a cohort of patients collected right before the coronary artery bypass grafting (CABG) surgery. We compared the miRNA levels of those who developed VS (VASO group) with those who did not (NONVASO group) after surgery. Six miRNAs (hsa-miR-548c-3p, -199b-5p, -383-5p -571 -183-3p, -30d-5p) were increased and two (hsa-1236-3p, and hsa-miR770-5p) were decreased in blood of VASO compared to NONVASO groups. Receiver Operating Characteristic (ROC) curve analysis revealed that a combination of the miRNAs, hsa-miR-30d-5p and hsa-miR-770-5p can be used as VS predictors (AUC = 0.9615, p < 0.0001). The computational and functional analyses were performed to gain insights into the potential role of these dysregulated miRNAs in VS and have identified the "Apelin Liver Signaling Pathway" as the canonical pathway containing the most target genes regulated by these miRNAs. The expression of the combined miRNAs hsa-miR-30d and hsa-miR-770-5p allowed the ability to distinguish between patients who could and could not develop VS, representing a potential predictive biomarker of VS.

Quality improvement program in Latin America decreases mortality after cardiac surgery: a before-after intervention study.

BACKGROUND: The current challenge of cardiac surgery (CS) is to improve outcomes in adverse scenarios. The aim of this study was to assess the impact of a quality improvement program (QIP) on hospital mortality in the largest CS center in Latin America. METHODS: Patients were divided into two groups: before (Jan 2013-Dec 2015, n = 3534) and after establishment of the QIP (Jan 2017-Dec 2019, n = 3544). The QIP consisted of the implementation of 10 central initiatives during 2016. The procedures evaluated were isolated coronary artery bypass grafting surgery (CABG), mitral valve surgery, aortic valve surgery, combined mitral and aortic valve surgery, and CABG associated with heart valve surgery. Propensity Score Matching (PSM) was used to adjust for inequality in patients' preoperative characteristics before and after the implementation of QIP. A multivariate logistic regression model was built to predict hospital mortality and validated using discrimination and calibration metrics. RESULTS: The PMS paired two groups using 5 variables, obtaining 858 patients operated before (non-QIP) and 858 patients operated after the implementation of the QIP. When comparing the QIP versus Non-QIP group, there was a shorter length of stay in all phases of hospitalization. In addition, the patients evolved with less anemia (P = 0.001), use of intra-aortic balloon pump (P = 0.003), atrial fibrillation (P = 0.001), acute kidney injury (P < 0.001), cardiogenic shock (P = 0.011), sepsis (P = 0.046), and hospital mortality (P = 0.001). In the multiple model, among the predictors of hospital mortality, the lack of QIP increased the chances of mortality by 2.09 times. CONCLUSION: The implementation of a first CS QIP in Latin America was associated with a reduction in length of hospital stay, complications and mortality after the cardiac surgeries analyzed.