Important healthcare differences exist between the US and Canada. The goal of this investigation is to compare clinical characteristics, treatment strategies and clinical outcomes of STEMI patients with COVID-19 infection treated in the US versus Canada.
Methods and Results
The North American COVID-19 Myocardial Infarction (NACMI) registry is a prospective, investigator-initiated study enrolling STEMI patients with documented COVID infection in the US and Canada. The primary end-point is in-hospital mortality. The secondary end-points include stroke, reinfarction and a composite of death, stroke or reinfarction. Of the 767 STEMI-COVID patients, 67 (9%) were from Canada and 669 (91%) from the US. Patients enrolled in Canada were more likely to present with chest pain (79% vs. 54%, p< 0.001), otherwise patients across both countries had comparable presenting demographics (Table 1). The proportion of patients not undergoing coronary angiography was significantly lower in Canada compared with the US (9% vs. 19%, p=0.039); of those who underwent angiography, no significant differences in reperfusion modalities were noted. Compared with the US, patients in Canada had a significantly lower unadjusted risk for in-hospital mortality (15% vs. 29%, p=0.016) and the risk for the composite of death, stroke or re-infarction (15% vs. 31%, p=0.006). Vaccination status was available in Canada 26 / 67 patients (unvaccinated 13, vaccinated 13) and US 328/ 669 patients (unvaccinated 282, vaccinated 46); a strong association between vaccination and adverse clinical composite is noted in both countries (Canada: 3/13, 23% (unvaccinated) vs. 0/13, 0% (vaccinated), p=0.22; and, US: 75/282, 27% (unvaccinated) vs. 6/46, 13% (vaccinated), p=0.048).