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

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• Pharmacological preconditioning: volatile anesthetics used for analgesia during

surgeries have been found to improve tolerance to myocardial ischemia and post-

ischemic recovery [ 56 ]. Since then, these agents have been extensively used in

patients undergoing surgery, especially when ischemia and reperfusion periods

are planned [ 56 ].

• Exercise preconditioning: previous studies indicate that aerobic exercise prior to

ischemia reperfusion improves myocardial tolerance to IRI [ 62 ] (Fig. 10.2C).

Repetitive exposure of the myocardium to ischemia eventually leads to cardiac

dysfunction, while prolonged pharmacotherapy leads to tissue desensitization [ 63 ].

Aerobic exercise therapy, by contrast, is pragmatic in that it is cost effective and

sustainable for extended treatment. Therefore, exercise preconditioning is consid-

ered the only viable therapy that may provide long-term protection against IRI from

a scientific perspective [ 64 ]. Several studies have demonstrated that exercise not

only reduces cardiovascular risk factors, such as hypertension and obesity, but also

promotes a direct effect on the myocardium protecting against IRI-induced arrhyth-

mias [ 9 , 65 , 66 ], myocardial stunning [ 67 – 69 ], and myocardial infarction [ 10 , 12 , 70 ].

4 Exercise-Induced Cardioprotection Against Ischemia/

Reperfusion Injury

Cardioprotection afforded by exercise represents an increasing field of research.

As seen in Fig. 10.3, the number of citations found on pubmed using the terms

“exercise” AND “cardioprotection” has risen significantly since 1987.

Fig. 10.2 Representative diagrams of strategies developed to counteract ischemia reperfusion
injury. (a) Ischemic preconditioning: repeated short episodes of ischemia followed by a subsequent
prolonged ischemic insult. (b) Ischemic post-conditioning: intermittent reperfusion interspaced
with brief periods of myocardial ischemia after a prolonged ischemic insult. (c) Exercise precon-
ditioning: aerobic exercise performed before ischemia reperfusion protects myocardium

J.P. Borges and K. da Silva Verdoorn