Author + information
- Received July 31, 2017
- Revision received September 6, 2017
- Accepted September 14, 2017
- Published online September 3, 2018.
- Enver Tahir, MDa,
- Jitka Starekova, MDa,
- Kai Muellerleile, MDb,
- Alexandra von Stritzky, MDb,
- Julia Münch, MDb,
- Maxim Avanesov, MDa,
- Julius M. Weinrich, MDa,
- Christian Stehning, PhDc,
- Sebastian Bohnen, MDb,
- Ulf K. Radunski, MDb,
- Eric Freiwald, MScd,
- Stefan Blankenberg, MDb,
- Gerhard Adam, MDa,
- Axel Pressler, MDe,
- Monica Patten, MDb and
- Gunnar K. Lund, MDa,∗ ()
- aDepartment of Diagnostic and Interventional Radiology and Nuclear Medicine, University Hospital Hamburg Eppendorf, Hamburg, Germany
- bDepartment of General and Interventional Cardiology, University Heart Center, Hamburg, Germany
- cPhilips Research, Hamburg, Germany
- dInstitute for Medical Biometry and Epidemiology, University Hospital Hamburg Eppendorf, Hamburg, Germany
- eDepartment of Prevention, Rehabilitation, and Sports Medicine, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
- ↵∗Address for correspondence:
Dr. Gunnar K. Lund, Department of Diagnostic and Interventional Radiology, University Hospital Hamburg Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
Objectives This study analyzed the presence of myocardial fibrosis detected by late gadolinium-enhancement (LGE) cardiac magnetic resonance (CMR) in correlation with the performance of competitive triathletes objectified by an exercise test and individual competition history.
Background Myocardial fibrosis detected by LGE CMR has been reported to occur in 0% to 50% of asymptomatic athletes. However, the cause and mechanisms of myocardial fibrosis are unclear.
Methods Eighty-three asymptomatic triathletes undergoing >10 training h per week (43 ± 10 years of age; 65% male) and 36 sedentary controls were studied by using LGE and extracellular volume (ECV) CMR. Parameters of physical fitness were measured by spiroergometry. Triathletes reported their lifetime competition results.
Results LGE CMR revealed focal nonischemic myocardial fibrosis in 9 of 54 (17%) male triathletes (LGE+) but in none of the female triathletes (p < 0.05). LGE+ triathletes had higher peak exercise systolic blood pressure (213 ± 24 mm Hg) than LGE− triathletes (194 ± 26 mm Hg; p < 0.05). Furthermore, left ventricular mass index was higher in LGE+ triathletes (93 ± 7 g/m2) than in LGE− triathletes (84 ± 11 g/m2; p < 0.05). ECV in LGE− myocardium was higher in LGE+ triathletes (26.3 ± 1.8%) than in LGE− triathletes (24.4 ± 2.2%; p < 0.05). LGE+ triathletes completed longer cumulative distances in swimming and cycling races and participated more often in middle and Iron Man distances than LGE− triathletes. A cycling race distance of >1,880 km completed during competition had the highest accuracy to predict LGE, with an area under the curve value of 0.876 (p < 0.0001), resulting in high sensitivity (89%) and specificity (79%). Multivariate analysis identified peak exercise systolic blood pressure (p < 0.05) and the swimming race distance (p < 0.01) as independent predictors of LGE presence.
Conclusions Myocardial fibrosis in asymptomatic triathletes seems to be associated with exercise-induced hypertension and the race distances. There appears to be a safe upper limit, beyond which exercise may result in myocardial fibrosis.
- athletes heart
- cardiac MR
- extracellular volume
- late gadolinium enhancement
- LV hypertrophy
- myocardial fibrosis
- T1 and T2 mapping
Dr. Stehning is an employee of Philips Research. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received July 31, 2017.
- Revision received September 6, 2017.
- Accepted September 14, 2017.
- 2018 American College of Cardiology Foundation
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