Post-COVID-19 vaccination occurrence of splenic infarction due to arterial thrombosis

We present the case of an 82-year-old woman admitted to a regional emergency general surgery centre with severe left upper quadrant abdominal pain and tenderness within 21 days of receiving the first dose of the ChAdOx1 nCov-19 vaccine (Vaxzevria, AstraZeneca). Following further investigation through CT imaging, a thrombus was discovered in the patient’s splenic artery resulting in a large splenic infarct. Splenic infarcts are rare and it is important to note the association between time of administration of the first dose of vaccine and the occurrence of thromboembolic complications in the noted absence of other risk factors for this condition. We hypothesise a link between Vaxzevria vaccine injection and a rare form of thromboembolic complication: thrombosis of the splenic artery.

Bowel Ischemia in COVID-19 Infection: One-Year Surgical Experience

Background COVID-19 is a deadly multisystemic disease, and bowel ischemia, the most consequential gastrointestinal manifestation, remains poorly described. Our goal is to describe our institution’s surgical experience with management of bowel ischemia due to COVID-19 infection over a one-year period. Methods All patients admitted to our institution between March 2020 and March 2021 for treatment of COVID-19 infection and who underwent exploratory laparotomy with intra-operative confirmation of bowel ischemia were included. Data from the medical records were analyzed. Results Twenty patients were included. Eighty percent had a new or increasing vasopressor requirement, 70% had abdominal distension, and 50% had increased gastric residuals. Intra-operatively, ischemia affected the large bowel in 80% of cases, the small bowel in 60%, and both in 40%. Sixty five percent had an initial damage control laparotomy. Most of the resected bowel specimens had a characteristic appearance at the time of surgery, with a yellow discoloration, small areas of antimesenteric necrosis, and very sharp borders. Histologically, the bowel specimens frequently have fibrin thrombi in the small submucosal and mucosal blood vessels in areas of mucosal necrosis. Overall mortality in this cohort was 33%. Forty percent of patients had a thromboembolic complication overall with 88% of these developing a thromboembolic phenomenon despite being on prophylactic pre-operative anticoagulation. Conclusion Bowel ischemia is a potentially lethal complication of COVID-19 infection with typical gross and histologic characteristics. Suspicious clinical features that should trigger surgical evaluation include a new or increasing vasopressor requirement, abdominal distension, and intolerance of gastric feeds.

Effect of COVID-19 pandemic on hip preservation surgery—a prospective surveillance from the UK Non-Arthroplasty Hip Registry

ABSTRACT A multi-centre, registry-based cohort study was conducted to assess the effect of the coronavirus disease 2019 (COVID-19) pandemic on the provision of non-arthroplasty hip surgery (NAHS) in the UK by (i) comparing the number of NAHS performed during the pandemic to pre-pandemic levels, (ii) prospectively auditing compliance to established guidance and (iii) evaluating post-operative outcomes and their predictors. Patients who underwent NAHS during the pandemic/pre-pandemic were selected from the Non-Arthroplasty Hip Registry, which collects demographic, procedural and pre-operative outcome data. Patients during the pandemic period were emailed separate COVID-19 surveillance questionnaires, which evaluated adherence to guidelines and post-operative outcomes. Fisher’s exact tests and logistic regression were used to identify predictors for developing COVID-19 and being re-admitted into hospital, post-surgery. There was a 64% reduction of NAHS performed during the pandemic compared to the pre-pandemic period. Ninety-nine percent of participants self-isolated, and 96.8% received screening, pre-operatively. No participant was COVID-19-positive peri-operatively. Post-operatively, participants had an intensive care unit admission rate of 2%, median hospital stay of 1 day, hospital readmission rate of 4.2%, COVID-19 development rate of 2.3% and a thromboembolic complication rate of 0.32%. No COVID-19-positive patient developed adverse post-operative outcomes. Participants who developed COVID-19 post-operatively had greater odds of having undergone osteotomy in comparison to arthroscopic surgery (P = 0.036, odds ratio = 5.36). NAHS was performed with good compliance to established guidance, and adverse operative outcomes remained low. If guidance is followed, the risk of COVID-19 post-op development is low. Although bigger operations have a slightly higher risk, this does not impact their prognosis.

Insights in ChAdOx1 nCov-19 Vaccine-induced Immune Thrombotic Thrombocytopenia (VITT)

SARS-CoV-2 vaccine ChAdOx1 nCov-19 (AstraZeneca) causes a thromboembolic complication termed vaccine-induced immune thrombotic thrombocytopenia (VITT). Using biophysical techniques, mouse models and analysis of VITT patient samples we identified determinants of this vaccine-induced adverse reaction. Super-resolution microscopy visualized vaccine components forming antigenic complexes with platelet factor 4 (PF4) on platelet surfaces to which anti-PF4 antibodies obtained from VITT patients bound. PF4/vaccine complex formation was charge-driven and increased by addition of DNA. Proteomics identified substantial amounts of virus production-derived T-REx HEK293 proteins in the EDTA-containing vaccine. Injected vaccine increased vascular leakage in mice leading to systemic dissemination of vaccine components known to stimulate immune responses. Together, PF4/vaccine complex formation and the vaccine-stimulated proinflammatory milieu trigger a pronounced B cell response that results in the formation of high-avidity anti-PF4 antibodies in VITT patients. The resulting high-titer anti-PF4 antibodies potently activated platelets in the presence of PF4 or DNA and polyphosphate polyanions. Anti-PF4 VITT patient antibodies also stimulated neutrophils to release NETs in a platelet PF4-dependent manner. Biomarkers of procoagulant NETs were elevated in VITT patient serum, and NETs were visualized in abundance by immunohistochemistry in cerebral vein thrombi obtained from VITT patients. Together, vaccine-induced PF4/adenovirus aggregates and proinflammatory reactions stimulate pathologic anti-PF4 antibody production that drive thrombosis in VITT. The data support a two-step mechanism underlying VITT that resembles the pathogenesis of (autoimmune) heparin-induced thrombocytopenia.

Silk® Flow Diverter Device for Intracranial Aneurysm Treatment: A Systematic Review and Meta-analysis

Flow diverters have become a critical instrument for complex aneurysms treatment. However, limited data are currently available regarding short and long-term outcomes for the Silk flow diverter. The objective of the study is to determine neurological prognosis and mortality rates for the Silk flow diversion device used in intracranial aneurysms. A systematic review with meta-analysis was performed using databases. The following descriptors were used for the search: “SILK”, “Flow Diverter”, “Mortality”, and “Prognosis”. The following data were extracted: mortality, good functional outcome, Glasgow outcome scale, complete or near-complete occlusion rates, rate of retreatment, and complications (thromboembolic and hemorrhagic complications). A total of 14 studies were selected. Among the 14 studies, 13 were retrospective observational cohort studies and 1 was a prospective observational cohort study. The mortality rate was 2.84%. The clinical good outcomes rate was 93.3%. The poor outcome rate was 6.6%. The overall thromboembolic complication rate was 6.06% (95% confidence interval [CI] 0.00–6.37, P=0.12, I²=3.13%). The total hemorrhagic complication rate was 1.62% (95% CI 0.00–5.34, P=0.28, I²=1.56%). The complete aneurysm occlusion rate was 80.4% (95% CI 8.65–9.38, P<0.0001, I²=9.09%). The Silk diverter device has a good safety and efficacy profile for treating intracranial aneurysms with high complete occlusion rates.

Heart Condition in Convalescents of Hemorrhagic Fever with Renal Syndrome According to Echocardiography Data

Aim. To study the morpho-functional parameters of the heart in convalescents of hemorrhagic fever with renal syndrome (HFRS) using echocardiography.Material and methods. The study included 27 patients without any chronic diseases who had severe or moderate HFRS (the main group) within 3 weeks after their discharge from the infection diseases hospital. The reference group consisted of 19 patients comparable by age and gender, without any chronic diseases. Transthoracic echocardiography was the basic method of heart and hemodynamics investigation. The test was performed using tissue Doppler and non-Doppler assessment of left ventricle systolic deformation method (speckle-tracking method).Results. Violation of longitudinal systolic deformation of the left ventricle was observed in 15 (55.6%) patients, which was combined with diastolic left ventricle filling by the type of relaxation violation in 8 (29.6%) cases. Mitral valve insufficiency of 1 degree was identified in 11 (40.7%) HFRS patients, insufficiency of the tricuspid valve of 1 degree was identified in 4 (14.8%) patients. Pericardial effusion was detected in 2 (7.4%) patients. In 7 (25.9%) patients in the first 3 weeks after discharge from the hospital, additional floating echoes were detected on the leaves and fibrous ring of the aortic valve, which were considered as a manifestation of thromboendocarditis.Conclusion. Further investigation is necessary to assess the prognostic value (including the risk of thromboembolic complication developing) of the changes revealed in HFRS convalescents and to support the inclusion of echocardiography in the examination program during dispensary observation of HFRS-convalescents.

Endovascular management of middle cerebral artery aneurysms (single-center case series study)

Background Middle cerebral artery (MCA) aneurysms were usually subjected to treatment by surgery, while endovascular treatment (EVT) was performed only in chosen patients. We assessed the efficacy, safety, and durability in addition to the clinical outcome of EVT when it is regarded as the first-line treatment modality for MCA aneurysms. Results We recruited 30 patients with MCA aneurysms who underwent definitive management from July 2017 to July 2018. All those patients were treated endovascularly; 22 patients (73.3%) presented with subarachnoid hemorrhage, and 8 patients (26.7%) had different presentations, including isolated headaches and seizures. EVT was performed for all patients and required the use of a balloon, stent, or double catheter techniques in 13 cases and flow diverter stents alone in two cases. Clinical outcome was assessed by the modified Rankin Scale (mRS) at 3 months. Angiographic follow-up was done by a conventional angiography at 6 months and after 1 year. EVT was efficiently conducted, leading to an outstanding accomplishment (mRS = 1–2) in 29 patients. However, one patient had a thromboembolic complication, followed by death after severe chest infection that was not related to the procedure. Immediate anatomical results included complete aneurysmal occlusion with the establishment of normal cerebral circulation. Angiographic follow-up revealed 24 unchanged occlusions and 5 cases with recanalization that required further treatment. Conclusion EVT of MCA aneurysms is a viable treatment option with positive outcomes in most cases. Nevertheless, the employment of long-term imaging follow-up is compulsory for validating such early results, often with respect to anatomical and functional stability.

A long journey to COVID-19 in obese patients

The paper reports clinical cases of obese patients who have had severe coronavirus infection (COVID-19): one case of damage to the gastrointestinal tract, and one case of neurological manifestation worsening (possible cognitive impairment). Assessment and therapeutic treatment of obese patients is challenging in terms of high thromboembolic complication rate. When choosing comprehensive treatment, dietary care and drug therapy, the improvement was observed in the form of gradual regression of disorders and further body weight reduction, which had a potential to affect the risk of complications, and to improve the overall quality of life of the patients.

Use of intravenous cangrelor and stenting in acute ischemic stroke interventions: a new single center analysis and pooled-analysis of current studies

Introduction Emergent stenting of both extra- and intracranial occlusions during acute ischemic stroke procedures is complicated by the need for immediate platelet inhibition to prevent thromboembolic complications. IV cangrelor is a relatively new antiplatelet that was initially approved for coronary interventions. Five prior case series have been published evaluating the results of IV cangrelor in neurointerventional procedures. We sought to combine the data from all prior studies and analyze only ischemic stroke interventions. Methods A prospectively maintained database was reviewed to identify all cases of IV cangrelor administration during acute ischemic stroke intervention. Nine additional patients were identified who have not been previously published. In addition, a literature search was performed to identify five prior publications of cangrelor in neurointervention. The data from these was combined with our institution in a pooled-analysis. Results Overall, 129 patients who received IV cangrelor during an acute ischemic stroke intervention were identified. The asymptomatic intracranial hemorrhage rate was 12.6%(11/87). The symptomatic intracranial hemorrhage rate was 6.2% (8/129). The rate of retroperitoneal hematoma and gastrointestinal bleeding were also low (1.5% and 0.8%, 2/129 and 1/129). There was one case of intraprocedural thromboembolic complication (0.8%) and no cases of intraprocedural in-stent thrombosis(0%). Conclusions IV cangrelor during acute ischemic stroke intervention appears to be safe, with a symptomatic intracranial hemorrhage rate of 6.2%. More research is needed to determine the ideal dosing regimen.