Myocardial fibrosis in athletes-Current perspective

Abstract

Several previous studies suggested that prolonged and extensive physical activity might lead to increased prevalence of myocardial fibrosis in athletes. The review summarizes these studies focusing on common patterns of myocardial fibrosis observed in athletes, their potential causes and significance. It also presents recent research on parametric imaging shedding new light on diffuse myocardial fibrosis in athletes. Finally, it reviews how these traditional and novel cardiac magnetic resonance (CMR) techniques can be incorporated in the diagnostic work up to differentiate athlete's heart from cardiomyopathies.

Keywords: T1-mapping; cardiac magnetic resonance; exercise; late gadolinium enhancement; physical activity; training.

Figure 1

Most common patterns of late gadolinium enhancement (LGE) observed in athletes. A,Short axis view, mid‐myocardial (nonischemic) LGE in the inferior insertion point in an asymptomatic 41‐year‐old ultramarathon runner without prior medical history (own data), B, three‐chamber view, mid‐myocardial (nonischemic) LGE in the basal inferolateral segment in an asymptomatic 41‐year‐old ultramarathon runner without prior medical history (own data), C, short axis view, subendocardial (ischemic) LGE in the mid inferolateral segment in an asymptomatic 52‐year‐old recreational runner without prior medical history (own data)

Figure 2

Most common patterns of late gadolinium enhancement (LGE) observed in athletes with different training history and in sedentary controls in relation to age. All drawings of the left ventricle are in short axis. Three groups are presented: on the left—lifelong athletes who start early in life mainly during adolescence (<20 years of age) and eventually become active or sedentary veteran athletes; in the middle—athletes who start later in life (>20‐30 years of age) and continue to become veteran athletes; on the right—sedentary controls. Patterns of fibrosis are described in text and presented in Figure 1. Studies demonstrate that most common patterns of fibrosis in athletes are insertion point fibrosis and myocarditis‐type fibrosis.16, 18, 19, 21, 22, 24 However, both of those patterns were also found in sedentary individuals.22, 29, 30, 36 Insertion point fibrosis seems both age and training related and therefore may occur earlier in athletes.5, 22, 24 Ischemic fibrosis was occasionally found with similar frequency in veteran athletes9 and sedentary individuals36