Scientists who studied human hearts found that infection appeared to make it harder for them to beat properly.
Feb. 20, 2023 By Kaitlin Sullivan
Covid can cause damage to the heart on a cellular level that can lead to lasting problems, including irregular heartbeats and heart failure, preliminary research suggests.
Covid’s effects on the heart have been well documented, but a new study zooms in on the microscopic changes thought to be caused by the virus.
Researchers from Columbia University in New York City examined autopsied heart tissue from people who had Covid, and found that the infection damaged the way cells in the heart regulate levels of calcium, a mineral that plays an important role in how the organ contracts and pumps blood throughout the body. In another part of the study, the same damage was seen in mice with Covid.
The findings, presented Monday at the Biophysical Society Meeting in San Diego, have not yet been published in a peer-reviewed journal.
When a person is infected with Covid, the immune system launches a hefty inflammatory response in an effort to fight off the virus. That inflammation, the new study found, disrupts how calcium is stored in the heart.
Calcium ions — a version of the element that carry a positive charge — are important messengers that regulate heart function, including how quickly and how forcefully the organ contracts. These ions are stored inside cells, on deck for when the body needs to use them. They’re released through channels in the cellular membrane, which ensures that just the right amount of calcium can get out.
The damage caused by inflammation during a Covid infection appears to prop these channels open, letting too much calcium leak from the cells of the heart, said Dr. Andrew Marks, a cardiologist and biophysics professor at Columbia University who co-led the study. This flood of calcium, he said, can decrease heart function and even cause fatal arrhythmias, or irregular heartbeats.
Although inflammation of the heart is a rare but documented side effect of the mRNA Covid vaccines, the study looked only at heart tissue from autopsies before vaccines were available.
“Whatever changes we saw were because of infection,” Marks said, adding that the new study was small, and the next step was to conduct the research on a larger scale.