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Before the 33rd Annual International Society for Heart and Lung Transplantation conference, there was significant intercenter variability in definitions of primary graft dysfunction (PGD). The incidence, risk factors, and outcomes of consensus-defined PGD warrant further investigation. We retrospectively examined 448 adult cardiac transplant recipients at our institution from 2005 to 2017. Patient and procedural characteristics were compared between PGD cases and controls. Multivariable logistic regression was used to model PGD and immediate postoperative high-inotrope requirement for hypothesized risk factors. Patients were followed for a mean 5.3 years to determine longitudinal mortality. The incidence of PGD was 16.5%. No significant differences were found with respect to age, sex, race, body mass index, predicted heart mass mismatch, pretransplant amiodarone therapy, or pretransplant mechanical circulatory support (MCS) between recipients with PGD versus no PGD. Each 10 minute increase in ischemic time was associated with 5% greater odds of PGD (OR = 1.05 [95% CI, 1.00-1.10]; p = 0.049). Pretransplant MCS, predicted heart mass mismatch ≥30%, and pretransplant amiodarone therapy were associated with high-immediate postoperative inotropic requirement. The 30 day, 1 year, and 5 year mortality for patients with PGD were 28.4%, 38.0%, and 45.8%, respectively, compared with 1.9%, 7.1%, and 21.5% for those without PGD (log-rank, p < 0.0001). PGD heralded high 30 day, 1 year, and 5 year mortality. Pretransplant MCS, predicted heart mass mismatch, and amiodarone exposure were associated with high-inotrope requirement, while prolonged ischemic time and multiple perioperative transfusions were associated with consensus-defined PGD, which may have important clinical implications under the revised United Network for Organ Sharing allocation system.

Introduction: Dementia has classically been identified to be of either vascular or neural origin. These domains overlap and are complementary, thus we consider dementia a disease of the single cerebrovascular unit. Our objective was to generate a modular platform for co-culture of brain microvascular endothelial cells and astrocytes that also incorporates mechanical stresses, and to then use this model of the cerebrovascular unit microenvironment to study the unit in vitro . Hypothesis: We assessed the hypothesis that endothelial health and blood-brain barrier integrity are modulated by shear stress and co-culture with astrocytes. Methods: We lithographed polydimethylsiloxane substrate on Teflon negative molds with subjacent rectangular channels of 0.45 and 2 mm depth for seeding of human brain microvascular cells and astrocytes, respectively, separated by a polytetrafluoroethylene (0.45 μm pore size) membrane under no flow or physiologic flow (6.2 dynes/cm 2 ) for one week. Immunocytochemical staining for glial fibrillary acidic protein and CD31 was simultaneously visualized by confocal microscopy. Cells from each channel were detached via trypsinization, and expression of transport proteins P-glycoprotein (P-gp) and glucose transporter-1 (GLUT-1), in addition to junction proteins zona occludens-1 (ZO-1) and CD31, was measured by Western Blot. Results: We stably co-cultured brain microvascular endothelial cells and astrocytes with no chamber leakage or mixing. CD31 staining revealed endothelial cell alignment to direction of flow. Expression of ZO-1 by endothelial cells increased in presence of flow and co-culture independently, by 1.6-fold in combined conditions relative to static monoculture (p Conclusion: Cell biology devoid of microenvironmental cues provides limited insight, especially when considering whole tissues, on the impact of disease. A co-culture system that introduces multiple cells, flow, controlled stress and independent visualization and sampling of each cell domain adds deeper understanding and greater value to in vitro biological models and tissue biology.