Vaccine Heartache

“I had my covid vaccine a few days ago and now I’ve got this pain in my chest and my breathing is more difficult than usual”.

This was the duty doctor call at the start of the week from a young student at my practice. I checked which vaccine he had received – Pfizer – and breathed a sigh of relief. At least it hadn’t been tarred with the same risks as the AZ vaccine. So was this simply post-vaccine anxiety?

Perhaps not.

No drug is entirely risk-free and many of us have been waiting for something to emerge with the new mRNA vaccines. Then a couple of weeks ago concerns were raised from the USA and Israel that Pfizer and Moderna vaccines had a “likely association” with myocarditis and pericarditis.

The MHRA has subsequently listed the two conditions in the special warnings section for the Pfizer vaccine.

Should we be concerned? Should our patients be concerned?

The short answer is no. But we do need to be aware of this as a possibility.

First, let’s keep things in perspective. As the BMJ reports there have been 1226 preliminary reports of these conditions after ~300 million doses of Pfizer and Moderna. Overall the risks are low. Indeed the MHRA comments that the 53 reports of myocarditis and 33 of pericarditis (one of which resulted in death) that occurred after use of the Pfizer vaccine is comparable to expected background rates. US data suggests rate may be marginally higher with the vaccine, hence the caution. 

The risk appears higher in younger people, especially adolescent males, is more likely after the second dose and may develop several days after the vaccine is administered. Cases are generally mild and tend to resolve following standard treatment – most need nothing more than NSAIDs alone.

No-one is suggesting this should stop vaccination but the MHRA comment “healthcare professionals should be alert to the signs and symptoms of myocarditis and pericarditis”. 

What do we need to look out for? New chest pain, shortness of breath and/or palpitations are the most common symptoms. Fatigue and fever may also occur. 

There isn’t further guidance on what to do with patients who do present with possible myocarditis or pericarditis but it seems prudent to make a thorough clinical assessment in primary care and seek help where there is uncertainty or concerning features. We should remember to report any possible cases by the Yellow Card scheme. 

Most importantly with the current data, we can reassure those who may be concerned about the risk that it is extremely low and these vaccines remain a very safe and highly effective option against covid-19.