Myocardial Infarction Following COVID-19 Vaccine Administration: Post Hoc, Ergo Propter Hoc?

Abstract

Vaccination against coronavirus disease 2019 (COVID-19) is the safest and most effective strategy for controlling the pandemic. However, some cases of acute cardiac events following vaccine administration have been reported, including myocarditis and myocardial infarction (MI). While post-vaccine myocarditis has been widely discussed, information about post-vaccine MI is scarce and heterogenous, often lacking in histopathological and pathophysiological details. We hereby present five cases (four men, mean age 64 years, range 50–76) of sudden death secondary to MI and tightly temporally related to COVID-19 vaccination. In each case, comprehensive macro- and microscopic pathological analyses were performed, including post-mortem cardiac magnetic resonance, to ascertain the cause of death. To investigate the pathophysiological determinants of MI, toxicological and tryptase analyses were performed, yielding negative results, while the absence of anti-platelet factor 4 antibodies ruled out vaccine-induced thrombotic thrombocytopenia. Finally, genetic testing disclosed that all subjects were carriers of at least one pro-thrombotic mutation. Although the presented cases do not allow us to establish any causative relation, they should foster further research to investigate the possible link between COVID-19 vaccination, pro-thrombotic genotypes, and acute cardiovascular events.

Cardiovascular complications of COVID-19 vaccines: A review of case-report and case-series studies

“…Some hypotheses can be made since there is currently no experiment being conducted to specifically examine the incidence of MI among recipients of the COVID-19 vaccine. First, it has been proposed that the thrombotic phenomenon following vaccination was caused by vaccine-induced thrombotic thrombocytopenia (VITT) as a possible mechanism, a condition related to heparin-induced thrombocytopenia 115 , 116 . The second hypothesis is that after vaccination, a supply and demand mismatch occurs in a diseased cardiovascular system 137 .…”

Lack of Evidence on Association between Iron Deficiency and COVID-19 Vaccine-Induced Neutralizing Humoral Immunity

“…Recently, lower hemoglobin and ferritin levels were strongly linked to severe outcomes of COVID-19, which placed a great burden on the vaccines to resolve that problem [ 16 , 17 , 18 , 19 , 20 ]. Yet, lower ferritin and hemoglobin levels have also been suggested to pose challenges for some vaccines effectiveness (e.g., Rubella, DPT, Haemophilus influenzae type b (Hib), Streptococcus pneumoniae serotype 1 (PS1)) [ 7 , 13 , 14 , 27 ]. Although a recommendation to correct iron level before receiving COVID-19 vaccination was raised, the picture with regards to the effect of iron level on COVID-19 vaccines effectiveness is still vague.…”

“…Iron is an important nutrient for the development of efficient immune response to infections and vaccinations [ 6 , 7 , 8 , 9 ]. The mechanisms underlying reduced effectiveness of host immunity under iron-deprived state is not fully understood.…”

“…Under the iron-deprived state, the immune system undergoes different alterations such as reduction in the number of CD4+ and CD8+ lymphocytes, and the levels of inflammatory cytokines [ 10 , 11 , 12 ]. Hypoferremia in animal models substantially decreased the effectiveness of immune response mediated by the effector and memory cells following vaccinations such as tetanus toxoid and Mycoplasma hyopneumoniae [ 7 , 13 ]. An independent study demonstrated suboptimal protective immunity induction following receiving diphtheria, pertussis, and pneumococcal (DPT) vaccines in children with ID compared to those with normal iron levels [ 14 ].…”

Same-Day Deaths After COVID-19 Vaccinations: Autopsy Findings in 54 Cases

“…We searched Medline using the key words “death”, “deaths”, “COVID-19”, “vaccine” and “vaccination” to identify same-day fatalities after COVID-19 vaccinations. Six reports 5–12 contained demographic and autopsy data on 54 patients (38 males and 16 females, age range 23-94) fulfilling the scope of our search (Table 1).…”