• Health

Current evidence shows COVID-19 vaccination doesn’t increase risk of sudden cardiac death

Posted on:  2024-04-22

Key takeaway

Sudden cardiac death (SCD) occurs when the heart loses functionality due to changes in the heart’s electrical signaling. There is no current evidence supporting a link between sudden cardiac death and COVID-19 vaccination. Myocarditis is inflammation of the heart muscle and is typically caused by infections like viruses. Studies have found a rare risk of myocarditis in young and adolescent males after the second dose of a COVID-19 mRNA vaccine. Not all cases of myocarditis lead to SCD.

Reviewed content


“COVID-19 vaccinations affect your risk” of sudden cardiac death

Source: Facebook, Instagram, Social media users, 2024-04-13

Verdict detail

Inadequate support: Current evidence doesn’t indicate a causal relationship between risk of sudden cardiac death and COVID-19 vaccination.

Full Claim

“Covid vaccinations affect your risk” of sudden cardiac death; COVID-19 vaccinations could cause "potential heart damage" that increase the risk of sudden cardiac death


In April 2024, a copy of a New Jersey doctor’s office policy regarding sports physicals for student athletes circulated on social media platforms including Facebook and Instagram. The policy stated that “Covid vaccinations affect your risk” of “sudden cardiac death on the playing field”. At the time of writing, one Instagram post sharing the policy had received nearly 6,900 likes.

This isn’t the first time this policy appeared in social media posts. Some of these posts date back to July 2022, when the policy was shared in a local Facebook group. Outlets including PolitiFact and New Jersey radio station 101.5 also previously fact-checked these posts.

What is sudden cardiac death (SCD)?

Sudden cardiac death (SCD) is an unexpected death that occurs in response to loss of heart function, typically within one hour of the onset of symptoms. Cardiac arrest causes the heart to stop pumping blood and can lead to SCD if not treated immediately with emergency interventions like cardiopulmonary resuscitation (CPR) and defibrillation.

Because the symptoms of cardiac arrest can begin suddenly and without warning in some people, it’s sometimes referred to as sudden cardiac arrest. According to the European Society of Cardiology (ESC):

“Most sudden cardiac arrests occur in the community and in individuals not previously known to have increased risk. A cardiac arrhythmia, called ventricular fibrillation, causes the heart to cease pumping and blood flow stops. If blood flow is not restored in time, the individual passes out and dies within 10 to 20 minutes.”

The Myocarditis Foundation and the ESC both say that sudden cardiac arrest generally can’t be reliably predicted. However, some health screenings, such as stress tests or electrocardiograms, may help to identify increased risk of cardiovascular disease.

Current evidence doesn’t support a connection between SCD and COVID-19 vaccination

Vaccines must adhere to strict safety standards. Different phases of clinical trials are required before vaccines are licensed and distributed for public use. Vaccines are also continuously monitored for risk of side effects and adverse events after they’ve been approved by the FDA.

Current evidence indicates that SCD isn’t a risk of COVID-19 vaccination.

In April 2024, the CDC published a study evaluating immediate or contributing causes of death via death certificates of young adults aged 16 to 30 in Oregon[1]. The aim of the study was to determine risk of SCD among adolescents and young adults after COVID-19 vaccination.

To do this, they examined deaths that weren’t caused by COVID-19 and could potentially be cardiac-related. They further narrowed down the deaths of interest by looking at only deaths that had occurred within 100 days of COVID-19 mRNA vaccination. The researchers chose this time period given evidence that adverse events associated with vaccination tend to occur within 42 days of vaccination.

From these remaining death certificates, just three deaths occurred within 100 days of an mRNA COVID-19 vaccination.

The researchers determined that death in all three cases was due to natural causes. More specifically:

“The first [male] death was recorded as having occurred in a natural manner 21 days after COVID-19 vaccination. The immediate cause of death noted on the death certificate was congestive heart failure attributed to hypertension […] The second decedent had received a COVID-19 vaccine dose 45 days before the date of death; the cause of death was recorded as ‘undetermined natural cause.’ […] Only one of these [female] deaths occurred within 100 days of having received an mRNA COVID-19 vaccine dose; the decedent died 4 days after COVID-19 vaccination. The manner of death was recorded as natural, and the immediate cause was listed as undetermined but as a consequence of chronic respiratory failure with hypoxia attributed to mitral stenosis.”[1]

A December 2023 study of Italian autopsy records also found no evidence to indicate an association between increased risk of SCD after COVID-19 vaccination[2]:

Causes of SCD in young people, including those who experienced SCD within 30 days of their COVID-19 vaccination, were consistent with prepandemic causes as established by rigorous autopsy.”[2]

Where did this claim stem from?

In 2021, Morris Sussex Direct Family Practice, a private general practitioner in Lake Hopatcong, New Jersey, instituted a new policy regarding sports physical clearance for student athletes. In the policy, the practice shared it wouldn’t clear student athletes to participate in sports without additional testing if they had received a COVID-19 vaccine.

The policy claimed this was a “precautionary” measure due to “worldwide experience and vaccine adverse event monitoring”. The practice still lists this policy on its website.

The policy may stem from concerns about the alleged link between myocarditis, COVID-19 vaccination, and sudden death. Science Feedback addressed this alleged link in previous claim reviews. As we explained, COVID-19 is a higher risk factor for myocarditis than COVID-19 vaccination.

Science Feedback reached out to Anthony Lucatorto, the physician who runs the practice, to verify the reasons for putting the new sports physical policy into place. His office confirmed that the policy was put into place in 2021, but did not provide specific reasons for instituting it. We will update this review if new information becomes available.

Likely origins of the alleged link between SCD and COVID-19 vaccination

Claims that COVID-19 vaccines increase the risk of SCD may be due to a conflation of SCD with myocarditis, a known side effect of COVID-19 mRNA vaccination.

Myocarditis is inflammation of the heart muscle. It’s a rare condition generally caused by viruses or infections, including COVID-19. While myocarditis often resolves with treatments such as rest and medication, it can sometimes permanently damage the heart muscle. This damage can introduce complications in the heart’s ability to pump blood and in some cases may lead to cardiac arrest and SCD.

Concerns regarding the risk of myocarditis after COVID-19 vaccination initially arose in April 2021 after reports of myocarditis surfaced in the Vaccine Adverse Event Reporting System (VAERS). VAERS data is used to identify potential patterns and safety problems with vaccines approved for use in the U.S.

As indicated in Figure 1 below, males aged 12 to 24 most commonly reported an incident of myocarditis to VAERS following COVID-19 vaccination. Reports of myocarditis among individuals within these age- and sex-stratified groups were highest after receiving a second dose of an mRNA COVID-19 vaccine.

Figure 1 – VAERS data of reported rates of myocarditis following mRNA COVID-19 vaccination as of 26 May 2022. Source: U.S. Food and Drug Administration (FDA)

The CDC further shared:

“Though cases of myocarditis and pericarditis are rare, when cases have occurred, they have most frequently been seen in adolescent and young adult males within 7 days after receiving the second dose of an mRNA COVID-19 vaccine.”

Several published studies have since shown there is indeed a rare risk of myocarditis after COVID-19 mRNA vaccination in young and adolescent males[3-7]. However, this association doesn’t automatically mean that vaccinated people also run a higher risk of SCD. As explained earlier in this claim review, current evidence doesn’t indicate a risk of SCD following COVID-19 vaccination.


Social media posts implying that COVID-19 mRNA vaccines cause SCD, based on a clinic’s policy of screening athletes’ heart health post-COVID vaccination, are unsubstantiated and misleading. Current evidence doesn’t support an association between an increased risk of SCD and COVID-19 vaccination. While myocarditis is a known risk factor of COVID-19 mRNA vaccination among young and adolescent men, conflating myocarditis risk and SCD, or assuming that all cases of myocarditis lead to SCD, is misleading.


Science Feedback is a non-partisan, non-profit organization dedicated to science education. Our reviews are crowdsourced directly from a community of scientists with relevant expertise. We strive to explain whether and why information is or is not consistent with the science and to help readers know which news to trust.
Please get in touch if you have any comment or think there is an important claim or article that would need to be reviewed.

Published on:


Related Articles