Risk of thromboembolic events in non-hospitalized COVID-19 patients: A systematic review.

The risk of thromboembolism in non-hospitalized COVID-19 patients remains uncertain and was assessed in this review to better weigh benefits vs. risks of prophylactic anticoagulation in this population. A search was performed through three databases: Medline, Embase, and Cochrane Library until 2022. Self-controlled case series, case-control and cohort studies were included, and findings summarized narratively. Meta-analyses for risk of thromboembolism including deep vein thrombosis (DVT), pulmonary embolism (PE), and myocardial infarction (MI) between COVID-19 and non-COVID-19 non-hospitalized patients were conducted. Frequency, incidence rate ratio (IRR), and risk ratio (RR) of stroke were used to assess risk in non-hospitalized COVID-19 patients considering the lack of studies to conduct a meta-analysis. Ten studies met inclusion criteria characterized by adult non-hospitalized COVID-19 patients. Risk of bias was relatively low. Risk of DVT (RR: 1.98 with 95% CI: 1.03-3.83) and PE (OR: 6.72 with 95% CI: 4.81-9.39 and RR: 4.44 with 95% CI: 1.98-9.99) increased in non-hospitalized COVID-19 patients compared to controls. Risk of MI (OR: 1.91 with 95% CI: 0.89-4.09) is possibly increased in non-hospitalized COVID-19 patients with moderate certainty when compared to controls. A trend in favor of stroke was documented in the first week following infection. Our meta-analyses support the increase in risk of DVT and PE, and likely increase of MI, in non-hospitalized COVID-19 patients. The risk of stroke appears significant in the first week following infection but drops to insignificance two weeks later. More studies are needed to establish evidence-based recommendations for prophylactic anticoagulation therapy in non-hospitalized COVID-19 patients.

Acute pulmonary emboli following rebound phenomenon after Nirmatrelvir/Ritonavir treatment for COVID-19.

The return of COVID-19 symptoms after Nirmatrelvir/Ritonavir (Nm/R) treatment is being increasingly reported. Limited evidence suggests most cases of rebound symptoms are mild and do not require further intervention. Here we present a male veteran reporting rebound symptoms who was found to be hypoxic with pulmonary emboli. Our case highlights the need to evaluate known complications of SARS-CoV-2 including venous thromboembolism in patients reporting recurring symptoms. Further, cases of severe rebound phenomenon should continue to be reported by clinicians to better appreciate the use of the Nm/R during the Omicron wave and among vaccinated persons.

Predicted and Observed Incidence of Thromboembolic Events among Koreans Vaccinated with ChAdOx1 nCoV-19 Vaccine.

We used the nationwide claims database to calculate the incidence of thrombotic events and predict their overall 2-week incidence. From 2006 to 2020, the incidence of deep vein thrombosis (DVT), pulmonary embolism (PE), and disseminated intravascular coagulation (DIC) tended to increase. Unlike intracranial venous thrombosis (ICVT) and intracranial thrombophlebitis (ICTP), which showed no age difference, other venous embolism, and thrombosis (OVET), DIC, DVT, and PE were significantly more common in over 65 years. The overall 2-week incidence of ICVT was 0.21/1,000,000 (95% confidence interval [CI], 0.11-0.32). ICTP, OVET, DIC, DVT and PE were expected to occur in 0.08 (95% CI, 0.02-0.14), 7.66 (95% CI, 6.08-9.23), 5.95 (95% CI, 4.88-7.03), 13.28 (95% CI, 11.92-14.64), 14.09 (95% CI, 12.80-15.37) per 1,000,000, respectively. To date, of 8,548,231 patients vaccinated with ChAdOx1 nCoV-19 in Korea, two had confirmed thrombosis with thrombocytopenia syndrome within 2 weeks. The observed incidence of ICVT after vaccination was 0.23/1,000,000.

A 59-Year-Old Woman with Extensive Deep Vein Thrombosis and Pulmonary Thromboembolism 7 Days Following a First Dose of the Pfizer-BioNTech BNT162b2 mRNA COVID-19 Vaccine.

BACKGROUND The COVID-19 pandemic is an ongoing cause of the current global healthcare crisis. Several vaccines were approved for use by emergency vaccination campaigns worldwide. At present, there are very few reports of COVID-19 vaccine-induced immune-thrombotic thrombocytopenia, a variant of heparin-induced thrombocytopenia (HIT), in comparison to the massive number of vaccinated people worldwide. CASE REPORT A 59-year-old woman presented to the Emergency Department with a 3-day history of sudden-onset left leg pain 7 days after receiving her first dose of BNT162b2 mRNA COVID-19 (Pfizer-BioNTech). She was diagnosed with deep vein thrombosis (DVT) and pulmonary embolism (PE) and found to have a positive HIT screen with optical density (OD) of 0.6 via ELISA test. She was hospitalized for 4 days and discharged home with an oral anticoagulant (rivaroxaban). CONCLUSIONS This case report describes a possible link between BNT162b2 mRNA COVID-19 (Pfizer-BioNTech) vaccination and thromboembolism. However, further data are needed to support such an association.

Reported adverse effects following COVID-19 vaccination at a tertiary care hospital, focus on cerebral venous sinus thrombosis (CVST).

Objectives: Several cases of unusual thrombotic events with thrombocytopenia were reported in several countries, in association with AstraZeneca's COVID-19 vaccine. The European medicines agency conducted a detailed review and concluded that there was no evidence to suggest an association of thrombotic events with the use of COVID-19 vaccine AstraZeneca.Methods: King Abdulaziz Medical City is a 1500 bed tertiary care hospital in Riyadh, Saudi Arabia; this study describes spontaneously reported vaccine adverse effects received through the hospital's internal electronic safety reporting system from December 2020 to 13 April 2021.We assessed each report for causality association utilizing the world health organization's (WHO) causality assessment of an adverse event following immunization (AEFI) classification 2nd Edition 2019.Results: The majority of the reported events were mild to moderate, there were five serious events, one reported cardiac arrest, two cerebral venous sinus thrombosis, and two pulmonary embolism. Clinical and laboratory summary of the five patients are presented in detail.Conclusions: Efforts of pharmacovigilance in mediating the rare risk of thrombosis associated with COVID-19 vaccine are crucial in providing awareness on the possible risk factors and signs/symptoms that should raise red flags.