Latest results from the North American COVID-19 STEMI (NACMI) registry reported a 25% reduction in early mortality in 2021 compared to 2020 among patients with ST-segment elevation myocardial infarction (STEMI) and COVID-19 infection and zero deaths for patients vaccinated against SARS-CoV-2.
The study’s principal investigator, Santiago Garcia (Christ Hospital, Cincinnati, USA) delivered the findings at the American College of Cardiology’s annual scientific sessions (ACC 2022, 2–4 April, Washington DC, USA), where he told attendees that the availability of vaccines significantly reduced hospitalisations and deaths due to COVID-19 infection among patients who had a STEMI.
“We observed a reduction in in-hospital mortality, our primary endpoint, from 33% in 2020 to 23% in 2021—a 25% decline after adjusting for age, sex, race, diabetes or other factors that could have played a role,” said Garcia. “We also saw a decline in our secondary endpoint—a composite of death, stroke or a repeat heart attack—from 35% in 2020 to 25% in 2021.”
The NACMI registry is a collaboration between Society for Cardiovascular Angiography and Interventions (SCAI), the American College of Cardiology (ACC) and the Canadian Association of Interventional Cardiology (CAIC). The registry was established in 2020 with the aim to define baseline characteristics and management strategies and outcome data for COVID-positive patients presenting with STEMI.
A total of 64 medical centres across North America and Canada contributed data to the registry. In the initial findings, it was reported that 33% of North American patients with both COVID-19 and a STEMI died in the hospital.
Vaccination data was available for 193 (54%) of the patients treated in 2021. Of these, 22 patients (11%) had been vaccinated, and none of these patients died while in the hospital. By contrast, 37 of the 171 unvaccinated patients (22%) died in the hospital—an in-hospital death rate considerably above the expected rate of about 4%-6% for patients who have had a STEMI, Garcia said.
“In 2020, before vaccines were available for COVID-19, we saw significantly more patients presenting to the hospital with shortness of breath as their primary symptom, rather than with the more typical heart-attack symptom of chest pain,” Garcia said. “Having shortness of breath, having an abnormal chest X-ray and needing to be on a ventilator were all factors that increased patients’ risk of dying. Yes, they had had a severe type of heart attack, but they did not necessarily die from the heart attack—they died from severe COVID-19. In 2021, however, the availability of vaccines significantly reduced hospitalizations and deaths due to COVID-19 infection, including among patients who had a STEMI.”
In total, 586 patients were examined, 227 who were treated in 2020 before vaccinations were made available and 359 in 2021 after emergency use authorisation (EUA) from the US Food and Drug Administration (FDA). Of the patient population, more than 70% were male and nearly 75% were aged 55 and over. Close to 70% had high blood pressure and nearly 45% were diabetic. Compared to 2020, the proportion of Caucasian patients was higher, and patients presented more frequently with typical ischaemic symptoms, the investigators report.
When looking at outcomes in 2021, the research team found that survival was significantly better when compared to 2020 with mortality dropping from 33% in 2020 to 23% in 2021.