A higher risk of thrombosis has been described as a prominent feature of COVID-19. This systematic review synthesizes current data on thrombosis risk, prognostic implications, and anticoagulation effects in COVID-19. We included 37 studies from 4,070 unique citations. Meta-analysis was performed when feasible. Coagulopathy and thrombotic events were frequent among patients with COVID-19, and further increased in those with more severe forms of the disease. We also present guidance on the prevention and management of thrombosis from a multidisciplinary panel of specialists from the Mayo Clinic. The current certainty of evidence is generally very low, and continues to evolve.

We compared apoptosis, cellular oxidative stress, and inflammation of cultured endothelial cells treated with sera from 130 subjects with peripheral artery disease (PAD) and 36 control subjects with high burden of co-morbid conditions and cardiovascular risk factors. Secondly, we compared circulating inflammatory, antioxidant capacity, and vascular biomarkers between the groups. The groups were not significantly different (p>0.05) on apoptosis, hydrogen peroxide, hydroxyl radical antioxidant capacity, and nuclear factor k-light-chain-enhancer of activated B cells. Circulating tissue necrosis factor alpha (TNFα) (p=0.016) and interleukin-8 (p=0.006) were higher in the PAD group, whereas vascular endothelial growth factor-A (VEGF-A) (p=0.023) was lower. PAD does not impair the endothelium beyond that which already occurs from co-morbid conditions and cardiovascular risk factors in subjects with claudication. However, subjects with PAD have lower circulating VEGF-A than controls, and higher circulating inflammatory parameters of TNFα and IL-8.

All patients surviving an acute aortic dissection require continued lifelong surveillance of their diseased aorta. Late complications, driven predominantly by chronic false lumen degeneration and aneurysm formation, often require surgical, endovascular, or hybrid interventions to treat or prevent aortic rupture. Imaging plays a central role in the medical decision-making of patients with chronic aortic dissection. Accurate aortic diameter measurements and rigorous, systematic documentation of diameter changes over time with different imaging equipment and modalities pose a range of practical challenges in these complex patients. Currently, no guidelines or recommendations for imaging surveillance in patients with chronic aortic dissection exist. In this document, we present state-of-the-art imaging and measurement techniques for patients with chronic aortic dissection and clarify the need for standardized measurements and reporting for lifelong surveillance. We also examine the emerging role of imaging and computer simulations to predict aortic false lumen degeneration, remodeling, and biomechanical failure from morphological and hemodynamic features. These insights may improve risk stratification, individualize contemporary treatment options, and potentially aid in the conception of novel treatment strategies in the future.

To provide direct comparison between apixaban and rivaroxaban in patients with acute cancer‐associated venous thromboembolism (Ca‐VTE), consecutive patients treated with apixaban, rivaroxaban, or enoxaparin at Mayo Thrombophilia Clinic (March 1, 2013 to January 31, 2018)) were followed prospectively. The primary effectiveness outcome was venous thromboembolism (VTE) recurrence, and the secondary was mortality. The primary safety outcome was major bleeding, the secondary clinically relevant safety outcome was non‐major bleeding (CRNMB), and the third a composite of major and CRNMB. There were 750 patients treated for acute Ca‐VTE with apixaban (n = 224), rivaroxaban (n = 163), and enoxaparin (n = 363) within 14 days of diagnosis and for at least 3 months, or until study event. Recurrent VTE was diagnosed in 11 receiving apixaban, 7 receiving rivaroxaban (apixaban vs rivaroxaban hazard ratio (HR) 1.31, 95% confidence interval (95% CI) 0.51‐3.36) and 17 in the enoxaparin receiving group (apixaban vs enoxaparin HR 1.14, 95% CI: 0.54, 2.42 and rivaroxaban vs enoxaparin HR 0.85, 95% Cl: 0.36, 2.06). There were 82 deaths in apixaban, 74 rivaroxaban (apixaban vs rivaroxaban HR 1.67, 95% Cl: 1.20, 2.33) and 171 in enoxaparin group (rivaroxaban vs enoxaparin HR 0.73, 95% Cl: 0.56, 0.96). Major bleeding occurred in 11 apixaban, 12 rivaroxaban (apixaban vs rivaroxaban HR 0.73, 95% Cl: 0.32, 1.66) and 21 enoxaparin group (apixaban vs enoxaparin HR 0.89, 95% Cl: 0.43, 1.84 and rivaroxaban vs enoxaparin HR 1.23, 95% Cl: 0.61, 2.50). The CRNMB rate was higher in rivaroxaban compared to apixaban (P = .03) and LMWH (P = .01) groups. Recurrence of VTE and major bleeding were similar in apixaban, rivaroxaban, and enoxaparin groups. Rivaroxaban was associated with higher CRNMB but lower mortality compared to apixaban and enoxaparin.

Summary. Background: Heparin-induced thrombocytopenia (HIT) is an adverse immune-mediated response to unfractionated heparin and, less commonly, low molecular weight heparin. It is associated with a high thrombotic risk and the potential for limb and lifethreatening complications. Argatroban is the only approved and currently available anticoagulant for HIT treatment in the USA. Objectives: To report safety and efficacy outcomes with bivalirudin for HIT treatment. Methods: We retrospectively examined records from our registry of patients with a suspected, confirmed or previous history of HIT and who had received bivalirudin for anticoagulation in a single tertiary-care center over a 9-year period. Results: We identified 461 patients who received bivalirudin: 220 (47.7%) were surgical patients, and 241 (52.3%) were medical patients. Of this population, 107 (23.2%) were critically ill, and 109 (23.6%) were dialysis-dependent. Suspected, confirmed and previous history of HIT were reported in 262, 124 and 75 patients, respectively. Of 386 patients with suspected or confirmed HIT, 223 patients (57.8%) had thrombosis at HIT diagnosis. New thrombosis was identified in 21 patients (4.6%) while they were on treatment with therapeutic doses of bivalirudin. No patient required HIT-related amputation. Major bleeding occurred in 35 patients (7.6%). We found a significant increase in major bleeding risk in the critically ill population (13.1%; odds ratio 2.4, 95% confidence interval 1.2-4.9, P = 0.014). The 30-day allcause mortality rate was 14.5% (67 patients), and eight of 67 (1.7%) deaths were HIT-related. Conclusion: Bivalirudin may be an effective and safe alternative option for the treatment of both suspected and confirmed HIT, and appears to reduce the rate of HITrelated amputation.

Background We compared (a) cellular reactive oxygen species (ROS) production, inflammation, and apoptosis of cultured endothelial cells treated with sera, and (b) circulating inflammatory, antioxidant capacity, vascular biomarkers, and calf muscle hemoglobin oxygen saturation (StO2) in men and women with PAD. A secondary aim was to compare exercise performance and daily ambulatory activity between men and women. We hypothesized that women would have more impaired endothelial cellular ROS, inflammation, and apoptosis than men, as well as worse systemic inflammation, antioxidant capacity, vascular biomarkers, calf muscle StO2, exercise performance, and daily ambulatory activity. Methods One hundred forty-eight symptomatic men and women with PAD were characterized on the endothelial effects of circulating factors present in the sera using a cell culture-based bioassay on primary human arterial endothelial cells. Patients were further evaluated on circulating inflammatory and vascular biomarkers, physical examination and medical history, exercise performance, calf muscle StO2 during exercise, and ambulatory activity monitored during one week. Results Cellular ROS production was higher in African-American women than in men (p = 0.021), but there was no gender difference in Caucasians (p = 537). Men and women were not significantly different on endothelial cell apoptois (p = 833) and NF-κB activity (p = 0.465). For circulating factors, additional gender differences were found when comparisons were made within each race. In African-Americans, women had higher intercellular cell adhesion molecule-1 (p = 0.022) and leptin (p < 0.001), whereas in Caucasians, women had higher matrix metallopeptidase 9 (p = 0.047), higher vascular cell adhesion molecule-1 (p = 0.047), and lower hepatocyte growth factor (p = 0.046). Overall, women had higher apolipoprotein CIII (p = 0.035), lower pain-free distance (p = 0.048) and total distance (p < 0.001) during the 6-minute walk test, shorter time for calf muscle StO2 to reach the minimum value during exercise (p = 0.027), and slower average cadence (p = 0.004) during daily ambulation. Conclusions African-American women with symptomatic PAD have a heightened oxidative status likely resulting in increased endothelial oxidative stress than men. Furthermore, women exhibit a more pronounced pro-inflammatory profile of circulating biomarkers than men, as well as more limited peripheral microcirculation, exercise performance, and ambulatory activity than men. The clinical significance is that women with symptomatic PAD are in greater need of clinical intervention to improve oxidative stress, inflammation, and microcirculation than men, which may, in turn, favorably impact their lower exercise performance and daily activity.

We compared apoptosis, cellular oxidative stress, and inflammation of cultured endothelial cells treated with sera from 156 subjects with peripheral artery disease (PAD) and 16 healthy control subjects. Furthermore, we compared circulating inflammatory, antioxidant capacity, and vascular biomarkers between the two groups. The PAD group had a 164% higher value for endothelial cell apoptosis (P < 0.001) and a 62% higher value for endothelial cellular reactive oxygen species production (P < 0.001) than the control group. Furthermore, the PAD group had lower systemic antioxidant capacity measured by hydroxyl radical antioxidant capacity activity (P < 0.001), higher inflammatory and vascular measures of high-sensitivity C-reactive protein (P < 0.001), interleukin-8 (P < 0.001), serum amyloid A (P < 0.001), vascular cell adhesion molecule-1 (P < 0.001), adiponectin (P < 0.001), apolipoprotein B (P = 0.013), apolipoprotein CIII (P = 0.035), lower vascular endothelial growth factor-A (P < 0.001), and hepatocyte growth factor (P < 0.001) than the control group. Subjects with PAD have greater endothelial apoptosis and oxidative stress than control subjects with low burden of comorbid conditions and cardiovascular risk factors. Furthermore, subjects with PAD have lower systemic antioxidant capacity and angiogenic measures and higher circulating inflammatory parameters.

The aim of the study was to determine whether gait characteristics were associated with endothelial cell inflammation, oxidative stress, and apoptosis and with circulating biomarkers of inflammation and antioxidant capacity in older patients with symptomatic peripheral artery disease (PAD). Gait measurements of 231 symptomatic men and women with PAD were assessed during a 4-m walk test. Patients were further characterized on endothelial effects of circulating factors present in the sera using a cell culture-based bioassay on primary human arterial endothelial cells and on circulating inflammatory and vascular biomarkers. In a multivariate regression model for gait speed, the significant independent variables were age (p < 0.001), intercellular cell adhesion molecule-1 (ICAM-1) (p < 0.001), diabetes (p = 0.003), sex (p = 0.003), and history of cerebrovascular accidents (p = 0.021). In multivariate analyses for gait cadence, the significant independent predictors included highsensitivity C-reactive protein (HsCRP) (p < 0.001), diabetes (p = 0.001), and hypertension (p = 0.001). In a multivariate regression model for gait stride length, the significant independent variables were HsCRP (p < 0.001), age (p < 0.001), ICAM-1 (p < 0.001), hypertension (p = 0.002), cellular reactive oxygen species production (p = 0.007), and sex (p = 0.008). Higher levels of circulating biomarkers of inflammation and endothelial cell oxidative stress were associated with slower gait speed, slower cadence, and shorter stride length in older symptomatic patients with PAD. Additionally, this profile of impaired gait was more evident in older patients, in women, and in those with diabetes, hypertension, and history of cerebrovascular accidents.