For a better understanding of how the COVID-19 pandemic and public health restrictions impacted infarct severity, the study authors noted reductions in admission rates, delays in catheterization laboratory activity and death rates during the pandemic.

Magnetic Resonance Imaging in Acute ST-Elevation Myocardial Infarction (MARINA-STEMI) cohort study participants treated with primary percutaneous coronary intervention (PCI) and included in the prospective study from 2015-2020 (n = 474) was categorized according to:

  • 2020 timeframes with and without major public health restrictions,
  • Dates of major public health restrictions in 2020 and the corresponding period between 2015 and 2019.

Cardiac magnetic resonance imaging was used to evaluate myocardial damage.

The following changes were observed during major public health restrictions in 2020 (n = 48) when compared to phases without major restrictions in 2020 (n = 101):

  • Infarct size increased (22 [IQR 12-29] vs. 14 [IQR 6-23]%, P < 0.01),
  • Higher frequency (77% vs. 52%, P < 0.01)
  • Microvascular obstruction was more severe (1.5 [IQR 0.1-11.4] vs. 0.2 [IQR 0.0-2.6]%, P < 0.01)
  • A higher rate of intramyocardial hemorrhage (56% vs. 34%, P = 0.02).

In adjusted analyses, these findings were consistent when comparing patients admitted in 2020 to patients in the "pre-pandemic" era (2015-2019). Despite significantly longer total ischemia times (P < 0.01) and higher frequency of pre-PCI Thrombolysis in Myocardial Infarction (TIMI) flow 0 during major restrictions (P = 0.03), patient characteristics were similar between groups.


Novel MRI mechanistic data suggest that infarct size, MVO, and IMH increased significantly in STEMI patients admitted during the COVID-19 pandemic associated with major public health restrictions. Although further study is needed to assess COVID-19's complete impact on STEMI patients, these results indicate worse short- and long-term outcomes.


Disease condition,Coronary artery disease,Myocardial infraction



Disease Condition ,Coronary Artery Disease,Myocardial Infarction