Wall motion abnormalities in male elite orienteers are aggravated by exercise

Abstract

During the period 1979-92, 16 (15 men and one woman) sudden unexpected cardiac deaths occurred among young Swedish orienteers. This finding indicated a sharp increase in the death rate of orienteers, and necropsy demonstrated that myocarditis was a common histopathological finding. Therefore, an extensive non-invasive cardiac investigation was performed. A total of 59 male élite orienteers (mean age 23 years) and 36 cross-country skiers and middle-distance runners (mean age 22 years), serving as controls, were examined by both echocardiography at rest and radionuclide ventriculography at rest and during exercise. Wall motion abnormalities were found in eight orienteers using echocardiography. The purpose of this study was to examine whether the group of orienteers with wall motion abnormalities found using echocardiography had a smaller increase in ejection fraction from rest to exercise using radionuclide ventriculography than the rest of the orienteers and the controls, indicating an aggravation of the wall motion abnormalities during exercise. There were no significant differences in the ejection fraction at rest between the groups. In the orienteers with wall motion abnormalities (group 1), 62% (five out of eight) had less than a 0.05 unit increase in left ventricular ejection fraction compared with 27% (14 out of 51) of the remaining orienteers (group 2) and 19% (7 out of 36) of the controls (group 3). A comparison of athletes in group 1 with those in groups 2 and 3 combined revealed a statistically significant difference (P < 0.05). The divergent response in left ventricular ejection fraction during exercise suggests an aggravation of the wall motion abnormalities with exercise. Both the echocardiographic and the radionuclide ventriculographic findings indicate that the orienteers in group 1 had concealed left ventricular damage.

Left ventricular volume changes during supine exercise in young endurance athletes

“…The intraobserver variability for left ventricular ejection fraction assessments has recently been described in our laboratory (Damm et al. 1999).…”

“Exercise‐Induced Cardiac Fatigue”—A Review of the Echocardiographic Literature

“…Interest in “exercise‐induced cardiac fatigue,” despite a lack of clarity as to its clinical consequences, has reached the public due to recent media headlines 6,7 and there is clearly some concern with respect to cardiovascular health and prolonged exercise 8 . A number of case studies have contributed to these concerns, including evidence of congestive heart failure 9 and ventricular wall motion abnormalities 10 following prolonged exercise and the evidence of myocardial fibrosis in a veteran endurance athlete 11 . The specific exercise parameters that augment cardiac fatigue are poorly described and the mechanisms involved in the process are unclear.…”

Myokarditis als Ursache des plötzlichen Herztodes bei Sportlern

“…Klinik der Myokarditis (modifiziert nach [5]). [20]. Allerdings schließt ein normales Echokardiogramm eine Myokarditis nicht aus [21].…”