Both COVID-19 and Vaccines Can Lead to Higher Risk of Heart Condition, Study Says

Syringes and vials of the Pfizer-BioNTech COVID-19 vaccine in Netanya, Israel, on Jan. 5, 2022. Jack Guez/AFP via Getty Images

A new study suggests that both COVID-19 infection and vaccination against the virus can increase the risk of postural orthostatic tachycardia syndrome (POTS), a condition that causes the heart to beat abnormally fast.

In a healthy person, the nervous system automatically tightens blood vessels and causes a moderate increase in heart rate to make sure a sufficient amount of blood reaches the brain. In most patients with POTS, however, this autonomic nervous system doesn’t properly function, forcing the heart to beat extra fast to compensate for the drop in blood supply to the brain. This usually results in dizziness, fainting, chest pain, and shortness of breath, especially when changing from a sitting position to a standing position.

For the study, published this week in Nature Cardiovascular Research, a team of scientists examined the post-vaccination POTS diagnoses of 284,592 adults from 2020 to 2022. A great majority of these patients received Pfizer-BioNTech (62 percent), Moderna (31 percent), and Johnson & Johnson (6.9 percent) vaccines.

“From this analysis, we found that the odds of developing POTS are higher 90 days after vaccine exposure than the 90 days prior to exposure,” Dr. Alan Kwan, the study’s first author and cardiovascular specialist at Cedars-Sinai Medical Center, said in a press release. “We also found that the relative odds of POTS were higher than would be explained by increases in visits to physicians after vaccination or infection.”

Specifically, the odds of developing POTS-related diagnoses after vaccination compared with before vaccination was 1.33. This is lower than the odds of getting a post-vaccination diagnosis of myocarditis (2.57), which is one of the most commonly reported adverse effects of COVID-19 vaccines and, for that reason, used as a benchmark in this study.

Researchers also looked at the diagnosis records of 12,460 Cedars-Sinai patients with COVID-19. When plotting both post-exposure odds and absolute rates of new diagnosis occurrence, they found that the post-infection risk of being diagnosed with POTS was 5.35 times higher after COVID infection than after vaccination.

“From these results, we can conclude that POTS might be occurring at a higher-than-expected frequency following COVID-19 vaccination, although at an overall rate lower than the frequency of POTS occurring following SARS-CoV-2 infection,” they wrote in the study.

While it’s unclear exactly how vaccination might be triggering POTS, the researchers said this might have to do with the fact that mRNA vaccines work by evoking an immunological response to the spike protein of the virus.

According to Kwan, the findings should prompt the medical community to study the link between this dysfunction of the autonomic nervous system and COVID-19 vaccines, but shouldn’t be taken as something discouraging vaccination.

“The main message here is that while we see a potential link between COVID-19 vaccination and POTS, preventing COVID-19 through vaccination is still the best way to reduce your risk of developing POTS,” Kwan said.

Dr. Madhava Setty, an anesthesiologist and senior science editor at online health news site The Defender, commented that the study should have also included people who received COVID vaccines but were still infected with the virus.

“In other words, they did not answer the big question, which is whether getting vaccinated would reduce your risk of getting POTS once you contracted COVID-19,” Setty said.

“Because the vaccine does not prevent infections, and we don’t know if vaccines mitigate the risk of getting POTS after COVID-19, we are left with no idea whether the risk outweighs the benefit.”