“Our results suggest that patients with heart failure should be prioritized for vaccinations and boosters against COVID-19,” said study author Dr. Caroline Sindet-Pedersen from Herlev and Gentofe Hospital, Hellerup, Denmark. “Vaccines against COVID-19 will continue to be important in preventing morbidity and mortality in vulnerable patient populations. Thus, studies emphasizing the safety of these vaccines are necessary to reassure those who may be hesitant and to ensure continued vaccine uptake.” Patients with heart failure are at increased risk of hospitalization, need for mechanical ventilation, and death due to COVID-19.2 Vaccination reduces the risk of severe illness from COVID-19. However, “Because of concerns about potential cardiovascular side effects from mRNA vaccines in patients with heart failure, this study examined the risk of cardiovascular complications and death associated with mRNA vaccines in a national cohort of patients with heart failure,” said Dr . Sindet-Pedersen. The study included 50,893 unvaccinated HF patients in 2019 and 50,893 HF patients in 2021 who were vaccinated with either mRNA vaccine (BNT162B2 or mRNA-1273).3 The two groups were matched for age, sex, and the duration of heart failure. The median age of the participants was 74 years and 35% were women. The median duration of heart failure was 4.1 years. Participants were followed for 90 days for all-cause mortality, worsening heart failure, venous thromboembolism, and myocarditis, starting on the date of the second vaccination for the 2021 group and the same date in 2019 for the unvaccinated group. The researchers compared the risk of adverse outcomes in the two groups, after standardizing for age, sex, duration of heart failure, use of heart failure medications, ischemic heart disease, cancer, diabetes, atrial fibrillation, and admission with heart failure less than 90 days. before the first follow-up date. Dr. Sindet-Pedersen explained: “Standardization mimics a randomized trial and is a way to get a better causal interpretation of results from observational studies.” Among 101,786 patients with heart failure, the researchers found that receiving an mRNA vaccine was not associated with an increased risk of worsening heart failure, myocarditis, or venous thromboembolism, but was associated with a reduced risk of all-cause mortality. The standardized risk of all-cause mortality within 90 days was 2.2% in the 2021 cohort (vaccinated) and 2.6% in the 2019 cohort (unvaccinated), indicating a significantly lower risk of all-cause mortality in 2021 compared with in 2019. The risk of heart failure worsening within 90 days was 1.1% in both cohorts. Similarly, no significant differences were found between groups for venous thromboembolism or myocarditis. Dr. Sindet-Pedersen concluded: “The study suggests that there should be no concern about cardiovascular side effects from mRNA vaccines in heart failure patients. Furthermore, the results show a beneficial effect of vaccination on mortality.” ENDS
