The researchers collected blood samples to test for high-sensitivity troponin percent and N-terminal pro-B-type natriuretic peptide and hematocrit. Cardiac MRI scans were performed to evaluate heart structure and function.

The 74 seropositive participants in the substudy and 75 age-, sex- and ethnicity-matched seronegative controls had an average age of 37. There were no differences between the seropositive and seronegative groups in cardiac structure (left ventricular volumes, mass and atrial area), in function (ejection fraction, global longitudinal shortening and aortic distensibility), tissue characterization, or biomarkers.

The new study is “definitely interesting,” said Dr. Saman Setareh, a senior cardiovascular fellow at Mount Sinai Heart in New York City. “Even though this is a very promising study and the authors should be congratulated on it, we have to be cautious (in interpreting it),” Dr. Setareh said. “It’s a small study with relatively young participants who had no comorbidities.”

“There is a lot that is unknown, and we are constantly learning more and more about COVID-19 long-term effects,” he added. “At Mount Sinai Heart, early on, a lot of young athletic patients who had just mild COVID-19 were barely able to exercise anymore. Part of that could be deconditioning.”

Dr. Setareh points to a recent study involving NBA players and staff. “In that study, 6 percent had measurable cardiovascular effects,” he said. “We have to look at patients more long-term. This study suggests that the likelihood of long-term effects on young patients with no comorbidities is low.”