Hussain, Md Walid Akram

Background Venous thromboembolism (VTE) is the most common cause of preventable mortality following colorectal surgery (CRS), occurring in about 2% of patients. As a result, prophylaxis including discharge chemoprophylaxis is recommended. While VTE risk assessment tools are available, the consistent adoption and utilization of these tools remains elusive. Our study objectives were to determine the utilization and impact of risk adjusted VTE prophylaxis in CRS patients. Study Design CRS cases performed between 1/1/2016 and 5/31/2021 were retrospectively analyzed. Caprini score and implemented VTE prophylaxis measures were determined. The primary outcome measure was receiving Caprini guideline indicated VTE prophylaxis. Secondary outcomes included VTE and bleeding. Categorical variables were compared by chi-square and Fisher’s exact tests, and continuous variables by Kruskal-Wallis test. Logistic regression models were used to determine predictors of receiving appropriate VTE prophylaxis or experiencing postoperative VTE and bleeding. Results 10,422 CRS cases were analyzed and 90.6% were high risk for VTE. In-hospital appropriate prophylaxis rates in low, moderate, high, and very high-risk category patients were 91.2%, 56.1%, 61.0%, and 63.1%, respectively. Inpatient VTE was reduced by 75% in those receiving appropriate VTE prophylaxis. At discharge, 5.8% of patients received appropriate prophylaxis, in whom there were no VTE events at 30- and 90 days from discharge. Increasing Caprini score positively correlated with VTE risk in both the inpatient and discharge cohorts, but inversely correlated with the likelihood of receiving appropriate prophylaxis at discharge (OR .31, P <.0001). Conclusion Caprini guideline indicated VTE prophylaxis in CRS patients reduced VTE events without increasing bleeding complications.

Coronavirus (COVID-19) infection exposes patients with heart failure to a higher risk of morbidity and mortality. In LVAD patients, one of the key problems that can lead to life-threatening low-flow or pump malfunction due to thrombus development in the inflow cannula, device body, or outflow graft, implicating hemodynamic instability, hemolysis, renal or hepatic failure, or cerebral or peripheral thromboembolism. [Endothelial protein C receptor and thrombomodulin levels are elevated along with procoagulants such as factor VIII, P-selectin, and von Willebrand factor and downregulated along with thrombomodulin as a result of the cytokine storm released by endothelial and immune cells. In general ,](#ref-0013) LVAD thrombosis has been found to occur in 2–13% of adult patients who use current continuous-flow devices. However, LVAD thrombosis due to COVID-19 is underreported and a few cases presented. We present a case of accelerated LVAD outflow thrombosis in the setting of COVID-19 infection with multiorgan failure.

Heart transplant remains the criterion standard treatment for patients in end-stage heart failure. Improvement in the post-heart transplant outcomes in the last decade has contributed to increased demand for organs. Worldwide each year, more than 5000 heart transplants are performed and 50,000 people become candidates for heart transplant. In the last 50 years, there have been several attempts to expand donor criteria to increase the donor pool. Despite making hepatitis C virus, opioid overdose death, old age allowable and changing the allocation system, the gap between supply and demand is widening and unfortunately, thousands die every year waiting due to the critical shortage of organs. New technologies for heart donation after circulatory death have emerged, particularly normothermic regional organ perfusion and ex-vivo heart perfusion using organ care systems. However, these technologies still do not fill the gap. Continuous advancements in areas such as regenerative medicine and xenotransplantation, among others, are needed to overcome the shortage of heart donors for heart transplantation.

Exosomes are membrane-enveloped nanosized (30–150 nm) extracellular vesicles of endosomal origin produced by almost all cell types and encompass a multitude of functioning biomolecules. Exosomes have been considered crucial players of cell-to-cell communication in physiological and pathological conditions. Accumulating evidence suggests that exosomes can modulate the immune system by delivering a plethora of signals that can either stimulate or suppress immune responses, which have potential applications as immunotherapies for cancer and autoimmune diseases. Here, we discuss the current knowledge about the active biomolecular components of exosomes that contribute to exosomal function in modulating different immune cells and also how these immune cell-derived exosomes play critical roles in immune responses. We further discuss the translational potential of engineered exosomes as immunotherapeutic agents with their advantages over conventional nanocarriers for drug delivery and ongoing clinical trials.