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brain, etc. Nevertheless, thus far, only a few studies have described the potential role
of Nrf2 and its non-pharmacological induction in cardiac aging. This chapter
explores the effects of various modes of exercise on Nrf2 signaling along with its
responses and ramifications on the cascade of OS in the aging heart.
Keywords Cardiovascular dysfunction • Aging • Exercise
1 What Is Cardiac Aging?
Any abnormal change that occurs in cardiovascular structure and function below or
above the optimal clinical threshold with age is termed as “Cardiac Aging”.
2 What If Cardiac Aging Is Unattended?
Like systemic aging, myocardial aging also occurs ubiquitously and inevitably.
Interesting is the fact that each organ can age at different a pace and at times, cardiac
aging can be independent of systemic aging. While the aging that results out of
natural deterioration of (i) myocardial structure-function, (ii) cardioprotective, and
(iii) repair processes is termed as normal or physiological cardiac aging, the patho-
logical cardiac aging refers to the one that is a resultant of non-normative events
such as stress, disease and/or any toxic challenges. It is to be noted that the normal
myocardial aging does not itself culminate in heart failure. At the same time, the
effect of normal (healthy) aging need not always be recognized and differentiated
from the effect of pathology, a thought set forth by Sobel [ 1 ]. In other words, the
two need not be looked independently either where one can aggravate the other.
Notably, certain normal age-related changes besides increasing the risk of develop-
ing CVD and CHD produces clinical heart complications such as amyloid heart
disease, protein aggregation disease, hypertrophic cardiomyopathy, aortic stenosis
and several others [ 2 – 4 ].
If both the normal and pathological cardiac aging is overlooked, over time, theycan progress and cannot be effectively managed leading to irreversible and com-
plete damage. This can pose economic burden not only at the individual level but
also at the societal level as well as the whole nation level. In addition to a decline in
the integrity of the cardiovascular system, if unattended, the financial burdens and
psychological complications due to disruption in maintaining independence in the
daily living of the affected individuals will emerge. This will lead to the feeling of
helplessness and other series of emotional disturbances that could cause an indirect
aggravating source of the existing cardiac complication leading to irreversible dam-
age in the aged population. Further, the individuals’ physical limitation in the form
of heart disease can extend to impact mental health that in turn, can seep into society
and burdening the latter in many forms including but not limited to (i) direct health
M. Narasimhan and N.-S. Rajasekaran