Heart problems after vaccinations are very rare—and often resolve quickly

New CDC data on myocarditis after a second dose of an mRNA vaccine suggests that the benefits still vastly outweigh the risks.

The teenager arrived at the Oregon Health & Science University Hospital in late April with chest pains that had started suddenly. An MRI showed myocarditis: a swelling of the heart muscle. It’s something doctors at the Portland hospital see in young people a handful of times a year, says Judith Guzman-Cottrill, a pediatric infectious disease physician.

But the timing caught her attention: Just a few days before his symptoms started, the boy had received his second dose of Pfizer’s COVID-19 vaccine. A couple weeks later, Guzman-Cottrill received a call from a colleague in Atlanta who told her about a similar patient with myocarditis that started two days after his second Pfizer shot. The same day, she got news via email of

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