Impact of COVID-19 Diagnosis on Mortality in Patients with ST-Elevation Myocardial Infarction Hospitalized during the National Outbreak in Italy.

Background. We sought to assess the clinical impact of COVID-19 infection on mortality in patients with ST-elevation myocardial infarction (STEMI) admitted during the national outbreak in Italy. Methods. We analysed a nationwide, comprehensive, and universal administrative database of consecutive STEMI patients admitted during lockdown for COVID-19 infection (11 March−3 May 2020) and the equivalent periods of the previous 5 years in Italy. The observed rate of 30-day and 6-month all-cause mortality of STEMI patients with and without COVID-19 infection during the lockdown was compared with the expected rate of death, according to the trend of the previous 5 years. Results. During the study period, 32.910 STEMI hospitalizations occurred in Italy. Among these, 4048 STEMI patients were admitted during the 2020 outbreak: 170 (4.2%) with and 3878 (95.8%) without a COVID-19 diagnosis. According to the 5-year trend, the 2020 expected rates of 30-day and 6-month all-cause mortality were 9.2% and 12.6%, while the observed incidences of death were 10.8% (p = 0.016) and 14.4% (p = 0.017), respectively. Excluding STEMI patients with a COVID-19 diagnosis, the mortality rate resulted in accordance with the prior 5-year trend. After multiple corrections, the presence of COVID-19 diagnosis was an independent predictor of all-cause mortality at 30 days [adjusted odds ratio (OR) 4.5; 95% confidence intervals (CI) 3.09−6.45; p < 0.0001] and 6 months (adjusted OR 3.6; 95% CI: 2.47−5.12; p < 0.0001). Conclusions.During the 2020 national outbreak in Italy, COVID-19 infection significantly increased the mortality trend in patients with STEMI.