Table 1.
Prevalence and patterns of myocardial fibrosis in athletic populations using CMR.
| References | Country | Study population | Exercise exposure | Age (y), mean ± SD | Sex | Prevalence of MF | Pattern/location of MF |
|---|---|---|---|---|---|---|---|
| Breuckmann et al. (8) | German | Marathon runners (n = 102) Age-matched control (n = 102) |
5 full-distance marathons during the past 3 years No exceptional endurance sports activity |
57 ± 6 | 100% male | Athletes: 12/102 Controls: 4/102 |
Athletes: 5 CAD pattern (involving the subendocardial layer and partial transmural spreading); 7 non-CAD pattern Controls: 2 CAD pattern; 2 non-CAD pattern |
| Wilson et al. (9) | UK | Lifelong veteran endurance athletes (marathon/triathlons) (n = 12) Veteran sedentary controls (n = 20) |
Competitive exercise training for many years No exercise training |
57 ± 6 60 ± 5 |
100% male | Athletes: 6/12 Controls: 0/20 |
Athletes: 1 CAD pattern (septal and lateral wall); 5 non-CAD pattern (epicardial lateral wall; basal and mid insertion point; inferior insertion point mid and apical; insertion point inferior mid/apical; inferior insertion point) |
| Altaha et al. (10) | Canada | Sub-elite athletes (running/cycling/triathlons) (n = 32) Recreational fitness participants (n = 4) |
>10 years of exercise <3 h exercise/week |
55 ± 5.6 | 69.4% male | Athletes: 4/32 Controls: 1/4 |
All appeared as minor LV LGE at the inferior RV hinge-point; no significant ischemic or non-ischemic LV LGE |
| Bohm et al. (11) | German | Elite master endurance athletes (marathon/triathlons/rowing/cyclist) (n = 33) Age-, height-, and weight-matched individuals (n = 33) |
Training history of ≥10 years and ≥10 h per week No exercise training |
47 ± 8 46 ± 9 |
100% male | Athletes: 1/33 Controls: 0/33 |
Athletes: 1 non-ischemic LV LGE; subepicardially in the LV posteroinferior region on the short-axis view |
| Sanchis-Gomar et al. (12) | Spain | Sub-elite and elite athletes (cyclists, runners) (n = 10) Age-matched controls (n = 5) |
Experience in competition for many years Never participated regularly in strenuous endurance; exercise performing <3 structured weekly training sessions |
40–70 | 100% male | Athletes: 2/10 Controls: 0/5 |
Athletes: 2 non-coronary pattern by LGE; LV lateral wall and basal segment of the inferolateral LV wall |
| Abdullah et al. (13) | USA | Masters athletes (triathlons/runners) (n = 21) Age- and gender-matched non-athletic control(n = 71) |
>3 h training/week at least during the last 25 years and regular competitions <3 h training/week at least during the last 25 years |
69.2 | 73% male | Athletes: 0/21 Controls: 1/71 |
Controls:1 small focus of LGE seen in the intraventricular septum close to the inferior right ventricular insertion point |
| Merghani et al. (14) | UK | Master athletes (cyclists/runners) (n = 152) Controls with similar age, sex, low Framingham 10 year CAD risk score (n = 92) |
≥10 miles running or ≥ 30 miles cycling per week for at least 10 years, completed at least 10 competition Engaged in exercise in accordance with the physical activity recommendations for health |
54.4 ± 8.5 | 70% male | Athletes: 16/152 Controls: 0/92 |
Athletes: 7 male athletes showed sub-endocardial LGE (consistent with myocardial infarction); 5 had a midmyocardial distribution and 3 had an epicardial distribution; 1 female athlete showed sub-endocardial LGE |
| Zaidi et al. (15) | UK | Master endurance athletes (n = 170) Age- and gender-matched non-athletic control (n = 130) |
Details were unavailable for both groups | 54.4 ± 8.5 | 71.2% male | Athletes: 69/170 Controls: 8/130 |
Details were unavailable |
| Domenech Ximenos et al. (16) | Spain | Highly trained endurance athletes (n = 93) Age- and gender-matched controls (n = 72) |
>12 h training/week at least during the last 5 years Details were unavailable |
35 ± 5.1 | 52% male | Athletes: 33/93 Controls: 4/72 |
Always confined to the hinge point; more details were unavailable |
| Pujadas et al. (17) | Spain | Healthy endurance Runners (n = 34) Age and body surface area matched controls (n = 12) |
10 years of training and with marathon times below 3 h and 15 min No exercise training |
48.1 ± 7.4 | 100% male | Athletes: 3/34 Controls: 0/12 |
Athletes: non-ischemic LGE pattern was noted: mesocardial in septal-apical wall, subepicardial in the inferior apical wall and mesocardial in the lateral wall |
| Tahir et al. (18) | Germany | Triathletes (n = 83) Age- and sex-matched controls (n = 36) |
>10 training hours per week or regularly participated in triathlons in the previous 3 years <3 h exercise per week | 43 ± 10 | 65% male | Athletes: 9/83 Controls: 0/36 |
Athletes: 5 triathletes had predominantly subepicardial LGE locations with a thin pericardial gap; 2 athletes had LGE located at the posterior right ventricle insertion point; 1 had an almost transmural LGE, but the sub-endocardial area was spared |
| Małek et al. (19) | Poland | Healthy ultra-marathon runners (n = 30) Age- and sex-matched controls (n = 10) |
Median 9 years of running with frequent competitions Not engaged in any regular activities |
40.9 ± 6.6 | 100% male | Athletes: 8/30 Controls: 1/10 |
Athletes: no cases of ischemic (sub-endocardial) LGE; 5 with a spotty-shaped, focal, midwall lower insertion point fibrosis; 3 with mid-wall or subepicardial, linear, very limited LGE Controls: 1 with spotty-shaped, focal, midwall lower insertion point fibrosis; no cases of ischemic (sub-endocardial) LGE |
CMR, cardiac magnetic resonance imaging; CAD, coronary artery disease; LV, left ventricular; LGE, late gadolinium enhancement; RV, right ventricular.