Absence of hypercoagulability after nCoV-19 vaccination: An observational pilot study

Abstract

Background It is still unknown whether COVID-19 vaccines induce a prothrombotic state or increase the hypercoagulable condition in subjects with a predisposition to thrombosis. Objectives We evaluated the coagulation profile in a series of healthy subjects who received the first dose of the BNT162b2 or the ChAdOx1 vaccines and assessed whether hypercoagulability developed. Patients/methods Volunteers among the staff of the University of Padua or health care professionals in the Padua University Hospital who had received either the ChAdOx1 or BNT162b2 vaccine in the previous 10 ± 2 days were eligible. A cohort of unvaccinated volunteers among family members of the University staff acted as control group. Global coagulation monitoring was assessed by whole blood rotational thromboelastometry, whole blood impedance aggregometry and thrombin generation. Platelet count was also obtained. Results One hundred and ninety subjects were enrolled: 101 (53.2%) received the ChAdOx1 vaccine and 89 (46.8%) the BNT162b2 vaccine. Twenty-eight non-vaccinated subjects acted as controls. Thromboelastometry parameters were all comparable among groups. Thrombin receptor activating peptide (TRAP)-, ADP- and ASPI-induced platelet aggregation were similar among groups, as well as platelet count. Endogenous thrombin potential (ETP) was comparable among groups. The results were confirmed after controlling for age, gender and hormonal. Considering women taking combined oral contraceptives or thrombophilia carriers, no differences were detected in thromboelastometry or thrombin generation parameters between subjects who received ChAdOx1 vs. BNT162b2 vaccines. Conclusions No significant activation of fibrinogen-driven coagulation, plasma thrombin generation or clinically meaningful platelet aggregation after ChAdOx1 or BNT162b2 vaccination was observed.

Stroke Associated with COVID-19 Vaccines

“…A prospective Chinese cohort study suggested that inactivated COVID-19 vaccine (BBIBP-CorV, Sinopharm) did not influence the profile of antiphospholipid antibody and anti-PF4heparin antibody nor increased the risk of thrombosis (60). Additionally, Campello et al (61) suggested that significant activation of fibrinogen-driven coagulation, plasma thrombin generation, or clinically meaningful platelet aggregation did not occur after ChAdOx1 nCoV-19 or BNT162b2 vaccination. Nevertheless, Simpson et al(62) evaluated associations between ChAdOx1 nCoV-19 or BNT162b2 vaccination and hematological and vascular adverse events.…”

COVID-19, Vaccines, and Thrombotic Events: A Narrative Review

“…Circulating platelets serve as a reservoir of immunomodulatory molecules [201]. However, no significant activation of fibrinogen-driven coagulation, plasma thrombin generation, or clinically meaningful platelet aggregation after AstraZeneca/Oxford or BNT162b2 vaccination was observed [209].…”

Post-SARS-CoV-2 vaccination venous sinus thrombosis: a literature review of 308 cases

“…Particularly, in case VST is associated with thrombocytopenia, the outcome can be fatal or unfavourable (Table 1 ). Though the pathophysiological mechanism underlying the development of thrombosis after SARS-CoV-2 vaccinations has not been fully elucidated, there are indications that the immune response towards the vaccine creates a state of hypercoagulability similar to hypercoagulability in SARS-CoV-2 infections [ 7 ], but hypocoagulability has been also reported [ 8 ]. This review aimed at summarising and discussing previous and recent advances regarding the diagnosis, pathogenesis, treatment, and outcome of post-SARS-CoV-2 vaccination venous sinus thrombosis.…”