Introduction
The benefit of exercise post-acute myocardial infarction (AMI) has been
investigated for several years and the vast majority of publications
have demonstrated a better prognosis related to this
practice.1-7. Physical activity post-AMI is associated
with better clinical evolution, with increased functional capacity and
less progression to heart failure, preventing malefic cardiac
remodeling.4, 8-10
This benefit has been mainly demonstrated in cases of AMI that result in
greater contractile involvement of the LV causing moderate to severe
systolic dysfunction (LVEF < 40%).11-18However, with greater dissemination of information regarding the
recognition of AMI “alarm symptoms”, greater promptness of care,
evolution of the therapies employed, less impairment of cardiac
contraction after AMI has become more frequent. So, observation of
ischemic cardiomyopathy with preserved LV systolic function or mild
dysfunction (LVEF 45% to 55%) is very common nowadays in the general
population. Regarding to all this, little is known about the real
benefit of exercise on LV remodeling and objective effect on LV
mechanics of contraction in this population.
Echocardiogram with speckle tracking technique can perform a
comprehensive study of LV contraction mechanics, which is characterized
by longitudinal apex-to-base shortening in association to segmental
rotations and ventricular torsion. This analysis adds numerous data over
a simple determination of LV ejection fraction.19-25
The present study aims to test the hypothesis that cardiovascular
rehabilitation under a supervised exercise program, in an uncomplicated
post-infarction population, would have a positive impact on the
mechanics of LV contraction.