To explore the incidence and potential mechanisms of oligosymptomatic myocardial injury following COVID-19 mRNA booster vaccination.
Hospital employees scheduled to undergo mRNA-1273 booster vaccination were assessed for mRNA-1273 vaccination-associated myocardial injury, defined as acute dynamic increase in high-sensitivity cardiac troponin T (hs-cTnT) concentration above the sex-specific upper-limit of normal on day 3 (48-96 h) after vaccination without evidence of an alternative cause. To explore possible mechanisms, antibodies against IL-1RA, the SARS-CoV2-Nucleoprotein(NP) and -Spike(S1) proteins and an array of 14 inflammatory cytokines were quantified. Among 777 participants, median age 37 years, 69.5% women, 40 participants (5.1% [95%CI, 3.7%-7.0%]) had elevated hs-cTnT concentration on day 3 and mRNA-1273 vaccine-associated myocardial injury was adjudicated in 22 participants (2.8% [95%CI, 1.7%-4.3%]). Twenty cases occurred in women (3.7% [95%CI, 2.3%-5.7%]), two in men (0.8% [95%CI, 0.1%-3.0%]). Hs-cTnT-elevations were mild and only temporary. No patient had ECG-changes, and none developed major adverse cardiac events within 30 days (0% [95%CI, 0%-0.4%]). In the overall booster cohort, hs-cTnT concentrations (day 3; median 5 [IQR, 4-6] ng/L) were significantly higher compared to matched controls (n = 777, median 3 [IQR, 3-5] ng/L, p < 0.001). Cases had comparable systemic reactogenicity, concentrations of anti-IL-1RA, anti-NP, anti-S1, and markers quantifying systemic inflammation, but lower concentrations of IFN-λ1(IL-29) and GM-CSF versus persons without vaccine-associated myocardial injury.
mRNA-1273 vaccine-associated myocardial injury was more common than previously thought, being mild and transient, and more frequent in women versus men. The possible protective role of IFN-λ1(IL-29) and GM-CSF warrant further studies. This article is protected by copyright. All rights reserved.