> We went into it thinking that [the risk] was going to be most pronounced and evident in people who smoked a lot or had diabetes, heart disease, kidney disease, or some [other] risk factors. What we found is that even in people who did not have any heart problems start with, were athletic, did not have a high BMI, were not obese, did not smoke, did not have kidney disease or diabetes—even in people who were previously healthy and had no risk factors or problems with the heart—COVID-19 affected them in such a way that manifested the higher risk of heart problems than people who did not get COVID-19.
They found that even mild COVID damaged otherwise healthy people's hearts so badly that their risk for heart problems are now comparable to those of obese people.
In other words, it does damage your heart. That damage might result in a heart attack, reflected in the increased hazard ratio.