COVID vaccination is not linked to cardiac arrest, study shows

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A study conducted in Victoria, Australia, has found no association between out-of-hospital cardiac arrests and COVID-19 vaccines.

The study was published in the journal Circulation and analyzed data from a unique registry established in 2019 to study out-of-hospital cardiac arrests.

The concern over potential cardiac complications of COVID-19 vaccines has led many cardiovascular disease experts to seek scientific evidence around this issue.

This study is one of the larger ones of its kind and aimed to document any possible relationship between out-of-hospital cardiac arrests and COVID-19 vaccinations.

Study Details

The researchers analyzed data from the EndUCD registry, which investigates all out-of-hospital cardiac arrests in people aged 1-50 years in Victoria.

The registry covers the period from April 2019 to March 2022 and provides detailed information on cardiac arrests by adjudicating against hospital and forensic data.

The study was conducted in three periods: before the pandemic (April 2019–Feb 2020), during the pandemic but preceding vaccine availability (March 2020–January 2021), and the period correlating with both COVID-19 presence in the community and vaccine availability (Feb 2021–March 2022).

The researchers compared the three periods against age-specific vaccination and COVID-19 rates for Victorians aged 1–50 years on a monthly basis.

Study Findings

The study examined whether rates of out-of-hospital cardiac arrest, fatal myocarditis, or unascertained out-of-hospital cardiac arrest increased after COVID-19 vaccination commenced.

It also looked at the causes of sudden death in young people within 30 days of their COVID-19 vaccination.

The researchers found that the analysis did not show increased rates of out-of-hospital cardiac arrest, fatal myocarditis, or unascertained out-of-hospital cardiac arrest during the pandemic or following the introduction of nationally mandated COVID-19 vaccination.

The study found that 2,242 people experienced out-of-hospital cardiac arrest during the study period.

There was no variation in median monthly rates of out-of-hospital cardiac arrest, heart attacks causing out-of-hospital cardiac arrest, or unascertained out-of-hospital cardiac arrest according to the defined time periods.

The study also looked at 38 cases of sudden death within 30 days of COVID-19 vaccination and found no difference in underlying causes of sudden death compared to previously-published, age-matched data.


Although COVID-19 vaccinations have been linked to cardiac complications such as myocarditis or pericarditis, the majority of these episodes have been reported to be mild.

The study’s findings showed no increase in death rates from these complications.

The study’s lead author, Dr. Liz Paratz, said that the scientific evidence is clear.

It can guide healthcare professionals and the government in reassuring people in the community about the safety of the vaccines with regard to out-of-hospital cardiac arrests and COVID-19 vaccination.

If you care about heart health, please read studies about how eating eggs can help reduce heart disease risk, and herbal supplements could harm your heart rhythm.

For more information about health, please see recent studies about new evidence on rare blood clots after COVID-19 vaccination, and results showing zinc could help reduce COVID-19 infection risk.

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