COVID-19 Vaccine and Potentially Related Thromboembolic Events: Case Series

The advent of multiple COVID vaccinations over the past year through an accelerated vaccine development process has led to concerns over its safety. The United States approved for emergency use the BNT162b2 (Pfizer-BioNTech), mRNA-1273 (Moderna), ChAdOx1 nCoV-19 (Oxford-AstraZeneca), and the Ad26.COV2.S (Janssen/Johnson & Johnson) vaccines. Although these vaccines have had a high safety profile, rare but serious adverse events have been reported including pulmonary embolism (PE) and cerebrovascular thrombosis. In this case series, we identified three patients admitted to Beaumont Hospital with new onset of pulmonary thromboembolism shortly after receiving the Pfizer-BioNTech vaccine. Clinical and laboratory data were obtained and reviewed from the Epic charting system. The three patients included two male and one female patient. All were older than the age of 40, obese with a BMI > 30 kg/m2, and had underlying vascular disorders including hypertension, coronary artery disease, and/or a history of a cerebrovascular accident. One patient was a current cigarette smoker, one had quit over 27 years ago, and the third patient never smoked. Two patients developed pulmonary embolism after the second dose of the Pfizer-BioNTech vaccine, while the third patient developed pulmonary embolism after the first dose. This case series illustrates a possible association between the Pfizer-BioNTech vaccine and the potential development of pulmonary thromboembolism, particularly in middle-aged, obese adults with underlying vascular disease. This is not surprising as recent research has seen higher incidence of thrombosis with other COVID-19 vaccinations including Moderna, Oxford-AstraZeneca, and Janssen/Johnson & Johnson. Identifying this possible association is crucial in early diagnosis and patient management, but more importantly in educating higher risk adults to avoid modifiable risk factors for venous thromboembolism including immobility, certain medications, and possibly postponing elective surgeries. Further prospective or retrospective cohort studies are warranted to assess this association.