Coronavirus disease 2019 infection and cerebrovascular diseases: an update on the pathophysiology and management.

PURPOSE OF REVIEW: COVID-19 is an ongoing global pandemic since it was first discovered in 2020. Cerebral vascular disease and stroke are among the most common and devastating neurological manifestations of COVID-19. This review offers an up-to-date information on the possible underlying mechanism of COVID-19-related stroke, its diagnosis, and management. RECENT FINDINGS: The thromboembolism associated with COVID-19 infection is likely related to the cytokine storm with innate immune activation, pulmonary disease leading to hypoxia-induced ischemia, thrombotic microangiopathy, endothelial damage and multifactorial activation of the coagulation cascade. Currently, there is no clear guidelines on the use of antithrombotics for the prevention and treatment of this phenomenon. SUMMARY: COVID-19 infection can directly cause a stroke or facilitate the formation of thromboembolism in the presence of other medical conditions. Physicians treating patients with COVID-19 should stay vigilant about the signs and symptoms of stroke, detect and treat early.

Extracardiac Prothrombotic Effects of COVID-19.

COVID-19 infection triggers a heightened inflammatory response which in turn, increases thrombosis and thromboembolism. Microvascular thrombosis has been detected in various tissue beds which may account for some of the multi-system organ dysfunction associated with COVID-19. Additional research is needed to understand which prophylactic and therapeutic drug regimens are best for the prevention and treatment of thrombotic complications of COVID-19.

Pathways of Coagulopathy and Inflammatory Response in SARS-CoV-2 Infection among Type 2 Diabetic Patients.

Chronic inflammation and endothelium dysfunction are present in diabetic patients. COVID-19 has a high mortality rate in association with diabetes, partially due to the development of thromboembolic events in the context of coronavirus infection. The purpose of this review is to present the most important underlying pathomechanisms in the development of COVID-19-related coagulopathy in diabetic patients. The methodology consisted of data collection and synthesis from the recent scientific literature by accessing different databases (Cochrane, PubMed, Embase). The main results are the comprehensive and detailed presentation of the very complex interrelations between different factors and pathways involved in the development of arteriopathy and thrombosis in COVID-19-infected diabetic patients. Several genetic and metabolic factors influence the course of COVID-19 within the background of diabetes mellitus. Extensive knowledge of the underlying pathomechanisms of SARS-CoV-2-related vasculopathy and coagulopathy in diabetic subjects contributes to a better understanding of the manifestations in this highly vulnerable group of patients; thus, they can benefit from a modern, more efficient approach regarding diagnostic and therapeutic management.

Efficacy and safety of direct oral anticoagulants versus vitamin K antagonists for left ventricular thrombus: an updated systematic review and meta-analysis.

Aim    To perform a systematic review and meta-analysis of efficacy and safety of direct oral anticoagulants (DOAC) as compared to vitamin K antagonists (VKA) in the treatment of left ventricular (LV) thrombosis.Material and methods    A search was performed in PubMed and Google Scholar for studies that compared DOAC and VKA in the treatment of LV thrombosis with respect of thromboembolic events, hemorrhagic complications, and thrombus resolution. The effect was evaluated with the odds ratio (OR) that was computed using a fixed effects model.Results    For these systematic review and meta-analysis, 19 studies were selected, including 2 randomized and 17 cohort studies. The articles included into these systematic review and meta-analysis, were published from 2018 through 2021. In total, 2970 patients (mean age, 58.8 лет; 1879 (61.2 %) men) with LV thrombus were included into the meta-analysis. Mean follow-up duration was 17.9 months. The meta-analysis showed no significant difference between DOAC and VKA in the incidence of the study outcomes: thromboembolic events (OR, 0.86; 95 % CI: 0.67-1.10; р=0.22), hemorrhagic complications (OR, 0.77; 95 % CI: 0.55-1.07; р=0.12), thrombus resolution (OR, 0.96; 95 % CI: 0.76-1.22; р=0.77). In a subgroup analysis, rivaroxaban compared to VKA significantly (79%) reduced the risk of thromboembolic complications (OR, 0.21; 95 % CI: 0.05-0.83; р=0.03) with no significant differences in hemorrhagic events (OR, 0.60; 95 % CI: 0.21-1.71; р=0.34) or thrombus resolution (OR, 1.44; 95 % CI: 0.83-1.31; р=0.20). The apixaban treatment group had significantly more (4.88 times) cases of thrombus resolution than the VKA treatment group (OR, 4.88; 95 % CI: 1.37-17.30; р=0.01); for apixaban, data on hemorrhagic and thromboembolic complications were not available.Conclusions    The therapeutic efficacy and side effects of the DOAC treatment for LV thrombosis were similar to those of VKA with respect of thromboembolic events, hemorrhage, and thrombus resolution.

Upregulation of Coagulation Factor VIII and Fibrinogen After Pulmonary Endarterectomy in Patients with Chronic Thromboembolic Pulmonary Hypertension.

OBJECTIVES: Chronic thromboembolic pulmonary hypertension (CTEPH) is associated with thrombotic states including elevated coagulation factor VIII (FVIII). Pulmonary endarterectomy (PEA) is the main treatment for CTEPH, and efficient anticoagulation is essential to prevent thromboembolism recurrence after surgery. We aimed to characterize longitudinal changes in FVIII and other coagulation biomarkers after PEA. METHODS: Coagulation biomarker levels were measured at baseline and up to 12 months after operation in 17 consecutive patients with PEA. Temporal patterns of coagulation biomarkers, and correlation of FVIII with other coagulation biomarkers, were analyzed. RESULTS: Baseline FVIII levels were elevated in 71% of the patients (mean 216 ± 67 IU/dl). FVIII doubled 7 days after PEA, peaking at 471 ± 87 IU/dl, and gradually returned to respective baseline levels within 3 months. Postoperative fibrinogen levels were also elevated. Antithrombin decreased at 1 to 3 days, D-dimer increased at 1 to 4 weeks, and thrombocytosis was observed at 2 weeks. CONCLUSIONS: FVIII is elevated in most patients with CTEPH. After PEA, early but transient elevation of FVIII and fibrinogen, and delayed reactive thrombocytosis, occurs, and warrants careful postoperative anticoagulation to prevent thromboembolism recurrence.

Gender Differences in Atrial Fibrillation: From the Thromboembolic Risk to the Anticoagulant Treatment Response.

Atrial fibrillation (AF) is the most common cardiac arrhythmia associated with an increased thromboembolic risk. The impact of the female sex as an independent risk factor for thromboembolic events in AF is still debated. Background and Objectives: The aim of this review is to evaluate the gender-related differences in cardioembolic risk and response to anticoagulants among AF patients. Materials and Methods: The PubMed database is used to review the reports about gender differences and thromboembolic risk in atrial fibrillation. Results: Non-vitamin K oral anticoagulants (NOACs) represent the gold standard for thromboembolic risk prevention in patients with non-valvular atrial fibrillation (NVAF). Despite a similar rate of stroke and systemic embolism (SE) among men and women in NOACs or vitamin K antagonists (VKAs) treatment, the use of NOACs in AF women is associated with a lower risk of intracranial bleeding, major bleeding, and all-cause mortality than in men. Conclusions: The female sex can be defined as a stroke risk modifier rather than a stroke risk factor since it mainly increases the thromboembolic risk in the presence of other risk factors. Further studies about the efficacy and safety profile of NOACs according to sex are needed to support clinicians in performing the most appropriate and tailored anticoagulant therapy, either in male or female AF patients.

Comparing Vitamin K Antagonists and Direct Oral Anticoagulants in Patients With Atrial Fibrillation Undergoing Transcatheter Aortic Valve Replacement: A Meta-Analysis.

Aortic stenosis (AS) is the most prevalent valvular disease in the elderly population and the prevalence of atrial fibrillation (AF) increases in the elderly population. Transcatheter aortic valve replacement (TAVR) becomes an important treatment for patients with AS at high surgical risk. This metanalysis aimed to compare the efficacy and safety of vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs) in patients with AF undergoing TAVR. We searched the different databases for articles published before January 31, 2022. In total, 7 studies including 25,255 patients were analyzed. Data on demographics, comorbidities, CHA2DS2-VASc score, Society of Thoracic Surgeons (STS) score, and incidences of all-cause mortality, major bleeding, intracranial hemorrhage (ICH), stroke, and thromboembolic events were obtained and analyzed. The VKA group had a lower CHA2DS2-VASc score (3.2 ± 1.2 vs 3.3 ± 1.2; P < .001) and a higher STS score (6.6 ± 3.2 vs 6.1 ± 2.9; P < .001) than the DOAC group. The risks of all-cause mortality (odds ratio [OR]: 0.88; 95% confidence interval [CI], 0.67-1.16), ischemic stroke (OR: 1.06; 95% CI, 0.90-1.24), and thromboembolism (OR: 1.24; 95% CI, 0.63-2.47) in the DOAC group were comparable to the VKA group. The risks of major bleeding (OR: 0.77; 95% CI, 0.71-0.84) and ICH (OR: 0.62; 95% CI, 0.42-0.90) were lower in the DOAC group compared to the VKA group. DOACs were associated with lower risks of major bleeding and ICH, and comparable risks of all-cause mortality, ischemic stroke, and thromboembolism in patients with AF undergoing TAVR compared to VKAs.

Activated 4-Factor Prothrombin Complex Concentrate as a Hemostatic Adjunct for Neonatal Cardiac Surgery: A Propensity Score-Matched Cohort Study.

BACKGROUND: Prothrombin complex concentrates are an emerging "off-label" therapy to augment hemostasis after cardiopulmonary bypass (CPB), but data supporting their use for neonatal cardiac surgery are limited. METHODS: We retrospectively reviewed neonates undergoing open heart surgery with first-time sternotomy between May 2014 and December 2018 from a hospital electronic health record database. Neonates who received activated 4-factor prothrombin complex concentrate (a4FPCC) after CPB were propensity score matched (PSM) to neonates who did not receive a4FPCC (control group). The primary efficacy outcome was total volume (mL/kg) of blood products transfused after CPB, including the first 24 hours on the cardiovascular intensive care unit (CVICU). The primary safety outcome was the incidence of 7- and 30-day postoperative thromboembolism. Secondary outcomes included 24 hours postoperative chest tube output, time to extubation, duration of CVICU stay, duration of hospital stay, 30-day mortality, and incidence of acute kidney injury on postoperative day 3. We used linear regression modeling on PSM data for the primary efficacy outcome. For the primary safety outcome, we tested for differences using McNemar test on PSM data. For secondary outcomes, we used linear regression, Fisher exact test, or survival analyses as appropriate, with false discovery rate-adjusted P values. RESULTS: A total of 165 neonates were included in the final data analysis: 86 in the control group and 79 in the a4FPCC group. After PSM, there were 43 patients in the control group and 43 in the a4FPCC group. We found a statistically significant difference in mean total blood products transfused for the a4FPCC group (47.5 mL/kg) compared with the control group (63.7 mL/kg) for PSM patients (adjusted difference, 15.3; 95% CI, 29.4-1.3; P = .032). We did not find a statistically significant difference in 7- or 30-day thromboembolic rate, postoperative chest tube output, time to extubation, incidence of postoperative acute kidney injury (AKI), or 30-day mortality between the groups. The a4FPCC group had a significantly longer length of intensive care unit stay (32.9 vs 13.3 days; adjusted P = .049) and hospital stay (44.6 vs 24.1 days; adjusted P = .049) compared with the control group. CONCLUSIONS: We found that the use of a4FPCC as a hemostatic adjunct for post-CPB bleeding in neonatal cardiac surgery was associated with a decrease in mean total blood products transfused after CPB without an increased rate of 7- or 30-day postoperative thromboembolism. Our findings suggest that a4FPCCs can be considered as part of a hemostasis pathway for refractory bleeding in neonatal cardiac surgery.

The Efficacy and Safety of Prolonged Oral Anticoagulation for the Prevention of Thromboembolic Events in Patients Recovered From COVID-19 1 Year After Hospital Discharge: The SARCOV-19 Prospective Registry.

Our objective in this study is to know the predictors of thromboembolic events 1 year after hospitalization for severe COVID-19 and the benefit of preventive oral anticoagulation for 1 month to placebo after release. We conducted a prospective study to determine the benefit of preventive anticoagulation upon discharge from the hospital and to determine the predictive factors of thromboembolic events. We included 720 patients in the SARCOV-19 Registry, with a mean age of 62.07 (±18.11), and 61.1% male. After 1 year, 60 thromboembolic events were observed, 45 in patients on a placebo, and 15 in patients on a direct oral anticoagulant. The predictive factors determined for these events were the presence of cardiac disease, elevation of D-dimer during hospitalization, myocardial damage defined by elevation of troponins more than 6 times normal, and the use of mechanical ventilation. However, the use of preventive anticoagulation protects against thrombotic events and reduces the risk of a thromboembolic event at 1 year with a relative risk of 0.49 compared to a placebo. The prolongation of the preventive anticoagulation at the exit will protect with a decrease of almost 50% of the risk against thrombotic events and this without increasing the risk of bleeding.

Amputation of arm after arterial thrombosis related to COVID-19 infection.

In this case report, a 75-year-old unvaccinated female patient presented with hypoxaemia, and she was admitted to an intensive care unit. After four days her left hand was discoloured blue, and fibrin D-dimer was elevated. An angiogram showed occlusion in the arteria radialis at the level of the bifurcature. Thrombolysis had no effect, and the patient's left arm was amputated above elbow level. COVID-19 is still a present problem worldwide, and it is important to be alert and aware of the risk of serious thromboembolic complications when treating unvaccinated patients.

Initiation and development of a percutaneous left atrial appendage closure programme: A French centre's experience and literature review.

BACKGROUND: Percutaneous left atrial appendage closure may be considered in selected patients with atrial fibrillation at significant risk of both thromboembolism and haemorrhage. AIMS: To report the experience of a tertiary French centre in percutaneous left atrial appendage closure and to discuss the outcomes compared with previously published series. METHODS: This was a retrospective observational cohort study of all patients referred for percutaneous left atrial appendage closure between 2014 and 2020. Patient characteristics, procedural management and outcomes were reported, and the incidence of thromboembolic and bleeding events during follow-up were compared with historical incidence rates. RESULTS: Overall, 207 patients had left atrial appendage closure (mean age 75.3±8.6 years; 68% men; CHA2DS2-VASc score 4.8±1.5 ; HAS-BLED score 3.3±1.1), with a 97.6% (n=202) success rate. Twenty (9.7%) patients had at least one significant periprocedural complication, including six (2.9%) tamponades and three (1.4%) thromboembolisms. Periprocedural complication rates decreased from earlier to more recent periods (from 13% before 2018 to 5.9% after; P=0.07). During a mean follow-up of 23.1±20.2 months, 11 thromboembolic events were observed (2.8% per patient-year), a 72% risk reduction compared with the estimated theoretical annual risk. Conversely, 21 (10%) patients experienced bleeding during follow-up, with almost half of the events occurring during the first 3 months. After the first 3 months, the risk of major bleeding was 4.0% per patient-year, a 31% risk reduction compared with the expected estimated risk. CONCLUSION: This real-world evaluation emphasizes the feasibility and benefit of left atrial appendage closure, but also illustrates the need for multidisciplinary expertise to initiate and develop this activity.

Bleeding on oral anticoagulants: overview of reversal strategies.

Oral anticoagulants (antivitamin K, direct oral anticoagulants) are routinely prescribed for the prevention or treatment of thromboembolic events, and many patients are now on long-term anticoagulant therapy. However, this complicates the management of urgent surgical conditions or major bleeding. Various strategies have been developed to reverse the anticoagulant effect and this narrative review provides an overview of the wide range of therapies currently available.

Medical record data-enabled machine learning can enhance prediction of left atrial appendage thrombosis in nonvalvular atrial fibrillation.

BACKGROUND: As a major complication of non-valvular atrial fibrillation (NVAF), left atrial appendage (LAA) thrombosis is associated with cerebral ischemic strokes, as well as high morbidity. Due to insufficient incorporation of risk factors, most current scoring methods are limited to the analysis of relationships between clinical characteristics and LAA thrombosis rather than detecting potential risk. Therefore, this study proposes a clinical data-driven machine learning method to predict LAA thrombosis of NVAF. METHODS: Patients with NVAF from January 2014 to June 2022 were enrolled from Southwest Hospital. We selected 40 variables for analysis, including demographic data, medical history records, laboratory results, and the structure of LAA. Three machine learning algorithms were adopted to construct classifiers for the prediction of LAA thrombosis risk. The most important variables related to LAA thrombosis and their influences were recognized by SHapley Addictive exPlanations method. In addition, we compared our model with CHADS2 and CHADS2-VASc scoring methods. RESULTS: A total of 713 participants were recruited, including 127 patients with LAA thrombosis and 586 patients with no obvious thrombosis. The consensus models based on Random Forest and eXtreme Gradient Boosting LAA thrombosis prediction (RXTP) achieved the best accuracy of 0.865, significantly outperforming CHADS2 score and CHA2DS2-VASc score (0.757 and 0.754, respectively). The SHAP results showed that B-type natriuretic peptide, left atrial appendage width, C-reactive protein, Fibrinogen and estimated glomerular filtration rate are closely related to the risk of LAA thrombosis in nonvalvular atrial fibrillation. CONCLUSIONS: The RXTP-NVAF model is the most effective model with the greatest ROC value and recall rate. The summarized risk factors obtained from SHAP enable the optimization of the treatment strategy, thereby preventing thromboembolism events and the occurrence of cardiogenic ischemic stroke.

Management of cardiovascular surgery in patients with systemic lupus erythematosus including thromboembolism and multiple organ failure prevention: A retrospective observational study.

Systemic lupus erythematosus is a chronic autoimmune disease that affects most tissues. Cardiovascular events are critical, life-threatening, long-term complications of systemic lupus erythematosus (SLE). We report our single-center experience of performing cardiovascular surgery in patients with SLE while avoiding postoperative complications. We also suggest a new approach for cardiopulmonary bypass and perioperative management. We applied the antiphospholipid antibody syndrome (APS) severity classification published by the Japan Intractable Disease Information Center to patients with SLE for perioperative management. Patients with Grade III or higher severity are treated with a slightly relaxed version of catastrophic APS therapy. This treatment modality includes glucocorticoids, anticoagulation, intravenous immunoglobulin, and plasma exchange. Between April 2010 and January 2021, 26 patients (2 males, 24 females) with SLE underwent cardiovascular surgery. The mean age was 74.2 ± 13.0 years (38-84 years). The primary outcomes were in-hospital mortality and long-term results, and the secondary outcomes were related to bleeding/embolization and coagulation function/platelet count. A subset analysis was performed to examine treatment efficacy in the APS Grade III or higher group. Of the 26 patients, 17 underwent valve surgery, 4 underwent isolated coronary artery bypass grafting, and 5 underwent thoracic aortic aneurysm surgery. There were no in-hospital deaths or associated bleeding/embolic complications. Postoperative antithrombin III decreased in patients who underwent valvular and aortic surgery, and platelet counts recovered to preoperative levels within 7 to 10 days. The 5- and 10-year survival rates were 80.5% and 53.7%, respectively. In addition, there were 10 patients with APS Grade III or higher, but there was no significant difference in the frequency of complications other than platelet recovery after treatment. The surgical outcome of open-heart surgery in patients with SLE was good. Surgical treatment of cardiovascular disease in these patients is difficult and complex. We focused on blood coagulation abnormalities and treated each patient by selecting the best individual treatment protocol according to the severity of the disease, taking into account the risk of bleeding and thrombosis. Management of blood coagulation function in these patients is essential, and careful therapeutic management should be considered during open-heart surgery.

The influence of blood composition and loading frequency on the behavior of embolus analogs.

In cases of acute ischemic stroke (AIS), mechanical thrombectomy (MT) can be used to directly remove lodged thromboemboli. Despite improvements in patient outcomes, one of the key factors affecting MT success is the mechanical properties of the occlusive thrombus. Therefore, the goal of this study was to investigate the viscoelastic properties of embolus analogs (EAs) and determine the influence of EA hematocrit and loading frequency. Bovine blood EAs were created over a range of physiological hematocrits (0-60%) and cyclic uniaxial compression testing was performed at three loading frequencies to mimic in vivo loading conditions, followed by stress-relaxation testing. It was found that EAs exhibited behaviors typical of hyper-viscoelastic materials and that EA hematocrit played a large role in both EA stiffness and relaxation, with both parameters decreasing as hematocrit increased from 0 to 60%. The viscoelastic behavior of the EAs was also affected by the frequency at which they were loaded, with significant increases in peak stresses between the 0.5 and 2 Hz loaded EAs. Lower hematocrit EAs had very dense fibrin networks while the higher hematocrit EAs consisted of closely packed RBCs with little fibrin present. These results suggest that fibrin contributes to EA stiffness and relaxation behaviors while RBCs play a role in decreasing the overall viscous response and strain-rate dependency. An Ogden hyperelastic model was found to best reproduce the EA loading data while a 3-term Prony series was fit to the stress relaxation data. A hyper-viscoelastic modeling framework was then implemented combining the loading and stress-relaxation fits and the results could match the full cyclic loading data for EAs of varying hematocrit and loading frequency. The results of the experimental mechanical characterization and hyper-viscoelastic curve fitting can be incorporated in future modeling efforts to optimize mechanical thrombectomy for AIS patients.

Clinical Validation of a Neointima-Inducing Inflow Cannula in a Continuous Flow Left Ventricular Assist Device.

Wedge thrombus formation around the inflow cannula of a continuous left ventricular assist device (LVAD) is a source of systemic thromboemboli. We previously reported the potential advantages of a new inflow cannula wrapped with titanium mesh (GU30) over the standard smooth surface oblique cut cannula (GU10). The objective of the present study was to clinically validate this new cannula. A retrospective cohort analysis of patients with implanted LVAD (EVAHEART) comparing the GU10 to the GU30 was conducted. Clinical outcomes, including survival, the incidence of thromboembolism, and bleeding events, were compared. Gross and histopathological analyses of explanted GU30 cannula were conducted following transplant or patient death. No significant differences in the survival rate, severe emboli, or cerebral bleeding were observed during the LVAD implantation. However, severe emboli occurred earlier after LVAD implantation when using the GU30 cannula compared with the GU10. In cases of long LVAD support, the neointima fully covered the inflow of the GU30 cannulae without wedge thrombus formation. The titanium mesh-wrapped inflow cannulae did not reduce the overall incidence of neurological events significantly. However, the titanium mesh-wrapped inflow cannula induced autologous neointimal growth over the cannula and prevented wedge thrombus formation in late-phase LVAD implantation.