Five of 789 professional athletes infected with COVID-19 were later found to have suffered inflammatory heart disease in the largest study to date on the cardiac impact of the virus in sports. In data published Thursday in JAMA Cardiology, doctors affiliated with six U.S.-based leagues followed the 789 infected players last year between May and October. Before returning to play, the athletes underwent three noninvasive tests that tracked heart rhythms, took an ultrasound of their hearts and measured a protein in their blood that can be a signal of heart damage. Thirty athletes had abnormal test results and were referred for a cardiac MRI. Doctors diagnosed five cases of inflammatory heart disease (0.6% of the total), with three cases identified as myocarditis and two as pericarditis. Dr. David Engel, a cardiologist at the Columbia University Irving Medical Center and one of the paper's lead authors, said the results were in line with current assessments that cardiac injury...