Impact of recurrent COVID-19 disease waves on acute myocardial infarction epidemics: results from a regional network.

Aims: To assess the impact of COVID-19 related public containment measures during recurrent COVID-19 waves on hospital admission rate for acute myocardial infarction (AMI). Methods and results: Clinical characteristics, reperfusion therapy modalities, COVID-19 status and in-hospital mortality of consecutive AMI patients who were admitted in a regional AMI network were recorded during one year starting in March 2020 and were compared with the year before. The COVID-19 study period encompassed two waves: the first in March-May 2020 and the second in October-December 2020. A total of 1349 AMI patients were hospitalised of which 725 during the pre-COVID period and 624 during the COVID period (incidence rate ratio of 1.16, p  = 0,006). The impact was predominantly present in the first wave (32% reduction: n  = 204 vs 152) and evanished during the second wave (3% increase (152 vs 156). A similar pattern was observed for ACS with cardiac arrest with a 92% reduction ( n  = 36 vs 3) during the first wave and no change during the second wave (18 vs 18). After correction for temperature and air quality, COVID-19 epidemic remained associated with a decrease of AMI hospitalisation ( p  = 0.046). Reperfusion strategy for AMI patients, were comparable between both study periods. The in-hospital mortality between the two periods was comparable (2.6% versus 1.9%), but COVID-19 positive ACS patients ( n  = 7) had a high mortality rate (14%). Conclusion: COVID-19 related public containment measures resulted during the first wave in a 32% reduction of AMI hospitalisation, but this impact was not visible anymore during the second wave.