Myocardial Fibrosis in Competitive Triathletes Detected by Contrast-Enhanced CMR Correlates With Exercise-Induced Hypertension and Competition History.
JACC Cardiovasc Imaging
; 11(9): 1260-1270, 2018 09.
Article
em En
| MEDLINE
| ID: mdl-29248656
ABSTRACT
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.Palavras-chave
Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Tipo de estudo:
Diagnostic_studies
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Etiology_studies
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Observational_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adolescent
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Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article