Exercise for Cardiovascular Disease Prevention and Treatment From Molecular to Clinical, Part 1

38

in 6 athletes (1%) an aneurism of aortic root was observed. A multiple linear regres-

sion analysis was made and it was demonstrated that BSA, type and duration of

competitive training were the only independent determinants of AoR dimension.

A large meta-analysis of 23 observational study [ 63 , 64 ] found that athletes have

larger aortic root diameters compared to sedentary subjects, especially at the sinuses

of Valsalva, that is statistically significant but not clinically significant. In this

research, the 95% confidence limit was only 33 mm for men and 27.3 for women,

respectively. Moreover, the physical exercise do not favour the enlargement of the

aortic root also in patient with a risk factor such as the bicuspid aortic valve (BAV)

but with normal aortic dimension [ 64 ]. It has been demonstrated that in 88 athletes

with BAV the increase was 0.98 mm/year, the same rate observed in non-athletes

with BAV (0.2–1.9 mm/year) [ 65 ]. These results demonstrate that the physical exer-

cise determine a small enlargement of the aortic root, as a consequence of physical

adaptation to the exercise, but it is never pathological and a marked enlargement

(>40  mm) suggests a pathologic process, that could be exacerbated by physical

exercise. Thus, it should be emphasized that subjects with aortic dilatation or pre-

disposition to rupture (for example Marphan’s syndrome) should be discouraged

from practicing intense physical exercise (both endurance than strength).

6 Conclusions

Exercise practice, both for recreational and competitive purpose, is spreading

worldwide. In fact, there are growing numbers of sports event (i.e., community-

based road running races) and in the last years there is a greater awareness of docu-

mented health benefits.

Then, an increase in the number of subjects with features of exercise-induced

cardiac remodeling could be expected. It is necessary for the cardiologist and sports

medicine practitioners to possess at least a basic knowledge of this subject. With

respect to the contemplated potential existence of an “exercise-induced cardiomy-

opathy” or of any potential excess of arrhythmias in athletes, it is critical to maintain

some balance. There is a multitude of positive effects from exercise and these are

very unlikely to be outweighed by any small risk of cardiac enlargement or arrhyth-

mias. However, there is lack of knowledge on the potential negative effects on

healthy of the “extreme” exercise. Data collection and new information should be

taken in order to identify the threshold beyond which the exercise becomes no lon-

ger beneficial to health.

References

1. Shiroma EJ, Lee IM (2010) Physical activity and cardiovascular health: lessons learned from
   epidemiological studies across age, gender, and race/ethnicity. Circulation 122(7):743–752

A. D’Andrea et al.