MYOCARDIAL INVOLVEMENT IN COVID-19 - DATA FROM 102 CLINICAL AND FORENSIC AUTOPSIES IN ST PETERSBURG DURING THE FIRST WAVE OF SARS-COV2 PANDEMICS

Background

Assessment of the link between SARS-CoV2 infection and the cause of death has been hampered by the limited number of autopsies performed during the pandemics. In Russia, the mandatory autopsy approach has been implemented for all cases of suspected covid-19 related deaths. Our aim was to describe the prevalence and extent of myocardial damage in patients deceased with covid-19.

Methods

Consecutive patients with covid-19 deceased during March-May 2020 in St Petersburg (Russia) underwent autopsy with post-mortem PCR on tracheal and/or pulmonary parenchymal tissue. Tissue PCR-positive cases (n=799) were further referred for histology assessment of pulmonary and extrapulmonary organ specimens through the central laboratory. Based on the extent of alveolar damage, covid-19 was categorized as being related to death or a concomitant condition not associated with death (covid-19 unrelated death). Myocardial involvement was assessed in a subset of clinical autopsies (n=42, 59% men, age 69±15 years) and all forensic autopsies (n=60, 48% men, age 77±11 years).

Results

Covid-19 was the primary cause of death in 67 and contributed to death in 13. In total, deaths were covid-19 related in 78%. Myocardial infarction was the cause of death in 2 (both covid-19 related) and contributed to death in 1, which was otherwise not related to covid-19. In 1 patient, death was caused by lymphocyte myocarditis with extensive non-coronary necroses. Interstitial edema and capillary erythrocyte aggregates were observed in 49 and not related to the presence of alveolar damage (p=1.000). In 12 of these, lymphomononuclear infiltration was noted, of which 2 cases fulfilled myocarditis criteria. Myocardial lymphomononuclear infiltration was observed in 11 of 82 patients (13%) who had significant alveolar damage and only in 1 of 20 (5%) those, who had no or minimal alveolar damage (p=0.452)

Conclusion

Systematically performed autopsies revealed causative association between SARS-CoV2 and death in the vast majority. Signs of myocardial involvement were observed in half and were not related to the extent of alveolar damage. Myocarditis appear to be a rare finding, though can be the primary cause of death.