COVID-19 mRNA Vaccines Found Safe in Patients with Heart Failure in Real-world Study

Use of SARS-CoV-2 mRNA vaccines in patients with heart failure (HF) was found safe and associated with a decreased risk of all-cause mortality, according to a new Danish real-world safety study presented at the European Society of Cardiology (ESC) Congress 2022.

Moreover, findings showed that the 2 mRNA vaccines—Pfizer-BioNTech’s BNT162B2 and Moderna’s mRNA-1273 vaccine—were not associated with an increased risk of worsening HF, venous thromboembolism, or myocarditis among more than 101 000 HF patients included in the study.

“Our results indicate that heart failure patients should be prioritized for COVID-19 vaccinations and boosters,” said presenting author Caroline Sindet-Pedersen, MD, postdoctoral researcher of Herlev and Gentofe Hospital, in Hellerup, Denmark, in an ESC press release. “COVID-19 vaccines will continue to be important for preventing morbidity and mortality in vulnerable patient populations. Thus, studies emphasizing the safety of these vaccines are essential to reassure those who might be hesitant and ensure continued uptake of vaccinations.”

Studies analyzing the safety and efficacy of mRNA vaccines have only included a small number of patients with HF. In addition, there have not been separate analyses conducted regarding the safety of mRNA vaccines in patients with HF, a population already vulnerable to COVID-19 infection, according to Sindet-Pedersen and colleagues.

To investigate the risk of worsening HF and all-cause mortality associated with mRNA vaccines, researchers used a Danish nationwide registry to identify 2 unique populations: all patients with HF in 2019; and all patients with HF in 2021 who received either the BNT162B2 or mRNA-1273 vaccines.


"Our results indicate that heart failure patients should be prioritized for COVID-19 vaccinations and boosters."


There were 50 893 patients in each cohort, and the median age of the total population was 74 years and 35% were women. The 2 arms were matched for age, sex, and duration of HF. Participants were followed for 90 days for all-cause mortality, worsening HF, venous thromboembolism, and myocarditis, starting from the date of the second vaccination for patients in the 2021 group and the same date in 2019 for those in the unvaccinated group.

Investigators found that the standardized risk of all-cause mortality within 90 days was 2.2% (95% CI, 2.1% to 2.4%) in the 2021 cohort and 2.6% (95% CI, 2.4% to 2.7%) in the 2019 cohort, showing a significantly lower risk difference for all-cause mortality in 2021 vs 2019 (risk difference: -0.3% [95% CI, -0.5% to -0.1%]).

The standardized risk of worsening HF within 90 days was 1.1% (95% CI, -1.0% to 1.2%) in the 2021 arm and 1.1% (95% CI, 1.0% to 1.2%) in the 2019 arm, showing no significant difference in the risk of worsening HF between the 2 groups (risk difference: 0% (95% CI, -0.1% to 0.1%). Investigators found no significant differences for venous thromboembolism or myocarditis.

“The study suggests that there should be no concern about cardiovascular side effects from mRNA vaccines in heart failure patients. In addition, the results point to a beneficial effect of vaccination on mortality,” concluded Sindet-Pedersen in the release.


Reference: Sindet-Pedersen C, Michalik F, Emanuel Strange J, et al. Risk of worsening heart failure and all-cause mortality following mRNA COVID-19 vaccination in patients with heart failure: a Danish nationwide real-world safety study. Presented at: ESC Congress 2022; August 26, 2022. https://www.escardio.org/Congresses-&-Events/ESC-Congress