Miscellaneous
Relation of Biomarkers and Cardiac Magnetic Resonance Imaging After Marathon Running

https://doi.org/10.1016/j.amjcard.2009.01.294Get rights and content

Although previous studies including endurance athletes after marathon running have demonstrated biochemical evidence of cardiac injury and have correlated these findings with echocardiographic evidence of cardiac dysfunction, particularly of the right ventricle, a study of marathon athletes incorporating biomarkers, echocardiography, and cardiac magnetic resonance (CMR) imaging has not been performed to date. The aim of this study was to demonstrate the cardiac changes associated with participation in a marathon using serial cardiac biomarkers, echocardiography, and CMR imaging. Fourteen participants (mean age 33 ± 6 years, 8 men) completed the full marathon. Myoglobin, creatine kinase, and troponin T were elevated in all athletes after the race. There was a strong linear correlation between right ventricular (RV) fractional area change as assessed by echocardiography and the RV ejection fraction as assessed by CMR imaging (r = 0.96) after the marathon. RV function, using echocardiography, transiently decreased from before to after the race (RV fractional area change 43 ± 4% vs 33 ± 5%, p <0.05). There were also postrace changes in left ventricular and RV diastolic filling. Although RV systolic changes were transient, left ventricular and RV diastolic abnormalities persisted up to 1 week after the marathon. No evidence of delayed enhancement of the left ventricular myocardium was found on CMR imaging, suggesting that the increase in cardiac biomarkers after the marathon may not have be due to myocardial necrosis. In conclusion, RV systolic dysfunction transiently occurs after a marathon and has been validated for the first time by CMR imaging. The increase in cardiac troponin after marathon running is likely due to the cytosolic release of the biomarker, not to the true breakdown of the myocyte, as confirmed by delayed enhancement CMR imaging.

Section snippets

Methods

A prospective study was performed on 14 amateur healthy volunteers participating in the 2008 Manitoba Marathon. Study subjects were randomly recruited, and written informed consent was obtained after local institutional board approval from the University of Manitoba. Subjects aged 18 to 45 years participating in the marathon (26.2 mi) were included. Patients with preexisting cardiovascular risk factors, including diabetes, hypertension, smoking, elevated lipids, and family histories of

Results

A total of 762 participants (545 men, 217 women) completed the 2008 Manitoba Marathon, with a mean finishing time of 254 ± 43 minutes. Our study population included 14 patients (mean age 33 ± 6 years), of whom 8 were men and 6 were women. Most patients (n = 10) were moderately trained, having run <40 mi/week (mean 26 ± 8 mi/week), and the remaining 4 were highly trained (mean 53 ± 12 mi/week). The mean time to completion of the full marathon was 245 ± 68 minutes. The subjects' weights, heights,

Discussion

In the present study, we confirmed the findings of previous studies that there is a significant increase in cardiac biomarkers of injury after prolonged exercise,6, 7, 8, 9, 10 with 100% of the participants demonstrating positive troponin levels. There was echocardiographic evidence of LV and RV diastolic dysfunction after completion of the marathon that had not completely normalized at 1-week follow-up. The RV systolic dysfunction detected by echocardiography after the marathon was validated

Acknowledgment

We would like to acknowledge and express our gratitude for the gracious support provided by management staff and volunteers of the 2008 Manitoba Marathon.

References (24)

Cited by (0)

The work was supported by funding from the St. Boniface General Hospital and Research Foundation, Winnipeg, Manitoba, Canada.

View full text