Myocardial Infarction and Exercise Training: Evidence from Basic Science

In 2016, cardiovascular disease remains the first cause of mortality worldwide [1]. Coronary artery disease, which is the most important precursor of myocardial infarction (MI), is the main component of total cardiovascular mortality, being responsible for approximately seven million of deaths [1]. In approximately 20% of infarcted patients, MI is recurrent in the first year after the event [2]. Moreover, among cardiovascular disease, coronary artery disease accounts for the most increased index of life years lost due to morbidity and/or mortality [1]. Sedentarism highly contributes to cardiovascular disease burden, especially for coronary artery disease, and is also one of the MI risk factors [3]. For many years, it was recommended to avoid physical activity after a cardiovascular event; nowadays, it is a consensus that exercise training (ET) should be part of cardiac rehabilitation programs. There is increasing evidence confirming that, when adequately prescribed and supervised, ET after MI can prevent future complications and increase the quality of life and longevity of infarcted patients [4, 5]. ET after MI follows international specialized guidelines; however, there are different protocols adopted by several societies worldwide in cardiac rehabilitation [6], and there is still lack of information on which type and regimen of exercise may be the ideal after MI, as well as how these exercises act to promote beneficial effects to cardiovascular and other organic systems. Thus, experimental studies are important contributors to elicit mechanisms behind clinical results, and to test and compare different ET protocols. Therefore, exercise prescription can be optimized, individualized, and safely practiced by patients. In this chapter, we present a brief review of MI pathophysiology followed by an updated discussion of the most relevant discoveries regarding ET and MI in basic science.