Cardiac abnormalities observed in some marathon runners following competition are transitory, believes an Indian origin scientist. He has also found that such abnormalities do not lead to damage of the heart muscle.
Previous studies have suggested that cardiac biomarkers are elevated in many casual, non-professional athletes following competition, which can lead to possible damage to the heart muscle.
However, the new study led by Dr. Davinder S. Jassal, assistant professor of cardiology, radiology and physiology at St. Boniface General Hospital Research Centre in Winnipeg, revealed that though the cardiac biomarkers were elevated post marathon, there was no evidence of direct permanent injury to the heart muscle.
"Although previous studies of marathon runners have demonstrated biochemical evidence of cardiac injury and have correlated these findings with echocardiographic evidence of cardiac dysfunction, this was the first time CMR has been used to further evaluate and understand the effects of marathon running on the heart," said Jassal.
During the study, the researchers examined cardiac health of 14 runners who participated in the full 2008 Manitoba Marathon in Winnipeg, Canada.
The echocardiograms and CMR performed immediately after competition revealed abnormalities, including irregularities in diastolic filling (relaxation abnormalities) on both sides of the heart and a decrease from 64 percent to 43 percent in the pumping function of the right ventricle.
"By using CMR, we were able to definitively show that these fluctuations do not result in any true damage of the heart, and the right ventricular dysfunction is transient, recovering one week following the race," Dr. Jassal noted.
The research was presented at the 105th International Conference of the American Thoracic Society in San Diego.