Impact of COVID-19 pandemic restrictions on ST-elevation myocardial infarction: a cardiac magnetic resonance imaging study.

AIMS: The severity of myocardial tissue damage following ST-elevation myocardial infarction (STEMI) strongly determines short- and long-term prognosis. This study explored the impact of the coronavirus disease 2019 (COVID-19) pandemic and associated public health restrictions on infarct severity. METHODS AND RESULTS: STEMI patients treated with primary percutaneous coronary intervention (PCI) and included in the prospective Magnetic Resonance Imaging in Acute ST-Elevation Myocardial Infarction (MARINA-STEMI) cohort study from 2015- 2020 (n = 474) were categorized according to (i) timeframes with and without major public health restrictions in 2020, and (ii) timeframes of major public health restrictions during 2020 and during the corresponding timeframes between 2015-2019. Myocardial damage was evaluated by cardiac magnetic resonance imaging. During major public health restrictions in 2020 (n = 48), there was an increase in infarct size (22 [IQR 12-29] vs. 14 [IQR 6-23]%, P < 0.01), a higher frequency (77% vs. 52%, P < 0.01) and larger extent of microvascular obstruction (1.5 [IQR 0.1-11.4] vs. 0.2 [IQR 0.0-2.6]%, P < 0.01) and a higher rate of intramyocardial haemorrhage (56% vs. 34%, P = 0.02) as compared to the phases without major restrictions in 2020 (n = 101). These findings were confirmed in adjusted analysis and were consistent when comparing patients admitted in 2020 versus patients admitted in the "pre-pandemic" era (2015-2019). Patient characteristics were comparable between groups, except for a significantly longer total ischemia time (P < 0.01) and higher frequency of pre-PCI Thrombolysis in Myocardial Infarction (TIMI) flow 0 during times of major restrictions (P = 0.03). CONCLUSION: This study provides novel mechanistic insights demonstrating a significant increase in myocardial damage in STEMI patients admitted during the COVID-19 pandemic with a temporal relation to major public health restrictions.

Effect of the COVID-19 Pandemic on Treatment Delays in Patients with ST-Segment Elevation Myocardial Infarction.

Coronavirus disease 19 (COVID-19) and its associated restrictions could affect ischemic times in patients with ST-segment elevation myocardial infarction (STEMI). The objective of this study was to investigate the influence of the COVID-19 outbreak on ischemic times in consecutive all-comer STEMI patients. We included consecutive STEMI patients (n = 163, median age: 61 years, 27% women) who were referred to seven tertiary care hospitals across Austria for primary percutaneous coronary intervention between 24 February 2020 (calendar week 9) and 5 April 2020 (calendar week 14). The number of patients, total ischemic times and door-to-balloon times in temporal relation to COVID-19-related restrictions and infection rates were analyzed. While rates of STEMI admissions decreased (calendar week 9/10 (n = 69, 42%); calendar week 11/12 (n = 51, 31%); calendar week 13/14 (n = 43, 26%)), total ischemic times increased from 164 (interquartile range (IQR): 107-281) min (calendar week 9/10) to 237 (IQR: 141-560) min (calendar week 11/12) and to 275 (IQR: 170-590) min (calendar week 13/14) (p = 0.006). Door-to-balloon times were constant (p = 0.60). There was a significant difference in post-interventional Thrombolysis in myocardial infarction (TIMI) flow grade 3 in patients treated during calendar week 9/10 (97%), 11/12 (84%) and 13/14 (81%; p = 0.02). Rates of in-hospital death and re-infarction were similar between groups (p = 0.48). Results were comparable when dichotomizing data on 10 March and 16 March 2020, when official restrictions were executed. In this cohort of all-comer STEMI patients, we observed a 1.7-fold increase in ischemic time during the outbreak of COVID-19 in Austria. Patient-related factors likely explain most of this increase. Counteractive steps are needed to prevent further cardiac collateral damage during the ongoing COVID-19 pandemic.