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

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In a group of 1309 athletes of different disciplines, 55% had an increased LV

end-diastolic diameter and 14% of endurance athletes show values more than

60 mm, that is compatible with DCM. However, the presence of a preserved LV

systolic function and a normal VO2 max during cardiopulmonary test may help to

exclude DCM [ 2 ].

In 947 elite athletes, maximal end diastolic septal wall thickness was ≤12 mm.

Only 1.7% had septal thickness ≥13 mm (range 13–16 mm). Septal thickness was

lower in women (mean value 9 mm; upper limits 12 mm). The black athletes show

often major LV wall thickness, with always a normal LV cavity, demonstrating that

the race is a predisposing factor to an increased wall thickness rather than to an

increased LV cavity [ 2 ]. LV hypertrophy with LV wall >12 mm is described in 13%

of black male athletes and in 3% of black female athletes. Anyway, a wall thick-

ness > 16 mm is very uncommon, irrespective of the race [ 3 ]. A recent interesting

review has proposed the upper limits of the LV dimension, stratified for age, sex and

race [ 48 ] (Table 2.1).

In athletes, the LV mass increase is always associated with a normal systolic

function. The ejection fraction is normal with an increased stroke volume at rest, as

a result of the increased pre-load (major end-diastolic diameters). By using TDI

method, also the systolic peak velocity of the lateral annulus of mitral valve (s’) is

demonstrated to be normal or supra-normal. It has been proposed a s’ cut- off

<9 cm/s in order to distinguish the pathological hypertrophy (HCM or Hypertensive

Cardiomiopathy) from the adaptation of the athlete’s heart [ 2 ].

The athletes LV diastolic function is normal or even super-normal at rest, in par-

ticular in endurance athletes. By using Pulsed-Doppler echocardiography, the trans-

mitral flow velocity expressed by the ratio E/A is >2 in athletes, because the large

LV volume of refill increases the contribution of early diastolic phase to during the

LV diastole. Instead, in pathological forms of LV hypertrophy the diastolic function

0

YACHTING

EQUESTRIAN

WRESTLING

WEIGHT-LIFTING

VOLLEYBALL

FENCING

ALPINE SKIING

HOCKEY

TENNIS

SOCCER

L.D. RUNNING

X-COUNTRY SKIING

SWIMMING

ROWING/CANOEING

CYCLING

10 20 30 40 50

Effect on LV

wall thickness

Effect on LV

cavity size

60 70

Impact of Type of Sport on LV Dimensions (%)

80 90 100

Fig. 2.4 Effect of different of 27 different sports on the LV cavity dimension and wall thickness
in elite athletes. LD long distance [ 3 ]

2 Acute and Chronic Response to Exercise in Athletes: The “Supernormal Heart”