Acute and mid-term outcomes of patients with st-elevation myocardial infarction during the covid-19 pandemic

Introduction. A reduction of admissions for ST-eievation myocardial infarction (STEMI) has been reported worldwide during the coronavirus disease 2019 (COVID-19) pandemic. However, most available data refer to March-April 2020. Lombardy region dramatically faced with COVID-19 both in the first (February 22th-June 11th) and in the second (September 14th-December 31th) outbreaks of 2020, and our center served as hub for STEMI with the network of care that was not modified by the decree of the healthcare Authorities, leading to an unbiased comparison with previous years. We aimed to compare admission, time of assistance, and outcomes of STEMI patients undergoing primary PCI (pPCI) during the first-outbreak, the second-outbreak, and the inter-outbreak phase of the COVID-19 pandemic, with the same corresponding periods of the previous year (2019). Methods. All consecutive patients who were hospitalized at Foundation IRCCS Polyclinic San Matteo (Pavia) for STEMI and underwent pPCI from February 22th to June H∗ (first COVID-19 outbreak), from September 14th to December 31th (second COVID-19 outbreak), and from June 12th to September 13m (inter-outbreak period) 2020 were included. Rates of admission and mortality at six months of the three study periods were compared with the corresponding periods of 2019. Survival analysis was made by applying the Kaplan-Meier method. The number of daily admission (NoDA) was calculated dividing the number of cumulative admissions by the number of days for each study period. Results. A total of 231 STEMI patients underwent pPCI from February 22 to December 31,2020: 86 during the first-outbreak, 71 during the second-outbreak and 74 during the inter-outbreak period. Although NoDA was reduced during both outbreaks, the difference with the previous year was greater during the second-outbreak: First-outbreak 0.77 (95% CI, 0.60-0.95) vs 0.88 (95% CI, 0.72-1.04) p=0.36;second-outbreak 0.64 (95% CI, 0.51-0.78) vs 0.87 (95% CI, 0.70-1.04) p=0.035. On the contrary, in the inter-outbreak period, we found a significant increase in NoDA compared to 2019, 0.78 (95% CI, 0.60-0.98) vs 0.51 (95% CI, 0.39-0.63) p=0.016. During the year 2020, a total of 19 in-hospital deaths was reported, with 12 of them occurring during the first outbreak (first outbreak 14% vs second outbreak 8.5% vs inter-outbreak 1.3%, p=0.015). Freedom from all-cause of death at 6-month was not different between 2020 and 2019 during all the three study periods: First-outbreak (95.9% vs 96.7, log-rank test p=0.78), second-outbreak (95.3% vs 95.4%, log-rank test p=0.97), inter-outbreak (94.2% vs 97.5%, log-rank test p=0.42). Conclusion. The reduction of admissions for STEMI was greater during the second rather than the first COVID-19 outbreak compared to the corresponding periods of 2019. Although high rates of in-hospital death, especially during the first-outbreak, were reported, survival at 6 months was not different compared to the previous year within all the three study periods.