| Currently it is observed that endurance athletes may have evidence of progressive ventricular dilatation, as well as systemically elevated biomarkers suggestive of myocardial injury during strenuous exertion. In addition, inflammatory markers may be elevated during intense exertion and experimental models have found that when exertion is combined with systemic inflammation, then cardiac dilatation and myocardial lesions can develop. To gain insight into whether physical exertion and systemic viral infections can induce myocardial injury, we hypothesized that (a) endurance athletes will present with previously sustained myocardial injury; (b) during intense physical exertion, endurance athletes will develop myocardial edema; and (c) common colds in endurance athletes will result in cardiac dilatation and myocardial inflammation.;Using cardiovascular magnetic imaging, we have found that in prospectively recruited healthy endurance athletes, more then 70% have evidence for myocardial scar tissue or irreversible injury, at rest. In those athletes who did have scar tissue, they tended to have larger left ventricles. When athletes were challenged with intense physical exertion, they developed myocardial edema. Furthermore, during an acute common cold, athletes developed persistent myocardial inflammation, as well as slight systolic impairment. These findings suggest that both physical exertion and performing sport during systemic viral illnesses may lead to cardiac injury. Hence, it may be the case that progressive ventricular dilatation observed in athletes may be caused by repetitive myocardial injury sustained during exertion and subclinical inflammation. |
