Abstract
BACKGROUND: We aimed to examine the effects of COVID-19 infection versus vaccination within the month prior to acute coronary syndrome (ACS) diagnosis with respect to their impact on the development of mortality or major adverse cardiovascular events (MACE). METHODS: This retrospective cohort study included patients hospitalized with a diagnosis of ACS between June 2020 and December 2022. Patients diagnosed with ACS were grouped according to the presence of COVID-19 infection (post-COVID), vaccination (post-vaccine), or non-exposure during the month prior to ACS diagnosis. Patients with and without MACE were also compared separately. RESULTS: We analyzed 1890 ACS patients (mean age 57.43 ± 11.53 years, 79.15% males). Of these, 319 (16.88%) were in the post-vaccine group, and 334 (17.67%) were in the post-COVID group. Major adverse cardiovascular events occurred in 569 (30.11%) patients. Mortality was recorded in 271 (14.34%) patients. In the post-COVID group, the frequencies of MACE and mortality and length of stay in hospital were significantly higher (vs. post-vaccine and vs. non-exposure groups; both P <.001). High age, ST-elevation myocardial infarction, having suffered from Post-COVID ACS, and high glucose were independently associated with increased MACE risk; whereas, hyperlipidemia, 3 or more COVID vaccinations, receipt of the Biontech vaccine, and high estimated glomerular filtration rate were independently associated with decreased MACE risk. CONCLUSION: Acute coronary syndrome patients who have recently had COVID-19 infection may have a worse prognostic course compared to those with recent vaccination, necessitating continuing care for pandemic-related risk factors as well as previously known factors impacting MACE and prognosis.