Concerns raised about legitimacy of research linking vaccines and heart attacks

30 November 2021
What was claimed

A study found the risk of a group of patients having a heart attack within five years increased from 11% to 25% after they were given their mRNA Covid-19 vaccine.

Our verdict

Serious concerns have been raised as to the quality of the research. Its publisher notes it may contain “potential errors”.

“What this research has shown is that markers associated with increasing the risk of heart attack and probably even progression of underlying heart disease in people who have already got some heart disease. There’s been a significantly increased risk from 11% at five years, the risk of heart attack, to 25%.”

A clip of health campaigner and cardiologist Dr Aseem Malhotra on GB News talking about claims linking the Covid-19 vaccines to heart attacks has gone viral on Twitter and been viewed at least one million times.

He did say the findings need to be replicated to confirm whether or not they are true, but what Dr Malhotra did not mention is that the journal which published an abstract of the research has issued an “expression of concern” about it, noting that it contains “potential errors” and “may not be reliable”.

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What the research claims

The research claims to have measured various biomarkers (biological characteristics like blood pressure) before and after patients received their second mRNA Covid-19 vaccine dose (such as the Pfizer or Moderna vaccines). 

It uses these biomarkers to calculate a “PULS score”, pre and post-vaccination, which it claims predicts the five-year risk of developing new acute coronary syndrome (ACS). ACS includes a range of conditions associated with reduced blood flow to the heart, including heart attacks.

The research claims that results from 566 patients showed the risk of developing ACS within five years, as measured by the PULS score, increased from 11% before vaccination to 25% after vaccination.

It was presented at a meeting of the American Heart Association (AHA) in the form of a poster (a format used by academics to present summary findings of research at conferences). Only the abstract has been published in an open-access format, though screenshots from the poster presentation are circulating on Twitter.


The “expression of concern”, issued by the AHA’s journal Circulation, raises a number of issues with the research. 

One issue is that “there are no statistical analyses for significance provided”, meaning that it is not clear if the results are due to chance or some other factor. The research claims a number of biomarkers indicating heart disease risk were elevated after vaccination, but some of these fall within the margin of error.

Of the three biomarkers mentioned in the abstract, only one increased by a statistically significant amount, and we only have the margins of errors listed in the abstract to base this on. As we’ve said, exactly how they may have been calculated is unclear.

Another issue is that the study doesn’t actually measure the risk of heart attacks directly, but the PULS score. 

There is little evidence on why this might be a reliable metric to measure the risk of heart attacks. 

Oncologist Dr David Gorski, notes that on the PULS test website, the evidence given for the claim that the test has been validated actually links to a paper which claims a different, though similar, biomarker test has been validated. 

Circulation also says of the research paper that “the author is not clear that only anecdotal data was used,” which means there may be an element of selection bias, affecting the legitimacy results.

Additionally, the research has not been peer-reviewed.

All these issues means the work cannot be used as a basis upon which to build the argument that Covid-19 vaccines increase the risk of heart attacks, as Dr Malhotra went on to say on GB News.

Other evidence

The Medicines and Healthcare products Regulatory Agency has identified an increased, though still low, risk of heart inflammation among young men in particular after receiving an mRNA vaccine.

It has also noted that a side effect of the vaccines is a rapid heartbeat.

It has not warned of any other link between the vaccines and any other heart condition.

People who experience adverse health events after vaccination can report them via the Yellow Card scheme to be investigated.

We deserve better than bad information.

After we published this fact check, we contacted GB News to ask them to add important context to their Twitter feed where they shared this video clip.

GB News did not respond.

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