Aging is a process characterized by a decreasing anabolic metabolism and regeneration capacity of the body, leading to irreversible changes in structure and functions. As the older population increases globally, recent studies have focused on a better understanding of the aging changes in the cardiac structure causing mortality and morbidity. It was proven that physiological changes with aging are the leading risk factor for cardiovascular diseases. This review aims to examine cellular mechanisms and investigate changes in the cardiac structure and physiology with the aging process in light of current information. Many theories explain cellular and molecular changes that play a significant role in aging. Decreased autophagy, increased mitochondrial oxidative stress, telomere length changes, mitochondrial dysfunction, changes in mTOR signals, errors in RNA coding, increase in cardiac fibrosis, altered Insulin Like-Growth Factor is fundamental accepted cellular theories currently. As a result of these processes at the cellular level, the effects of aging are seen as structural-functional differentiations in the myocardium, cardiovascular and nervous systems. Changes in the vascular system begin in endothelial cells, and the loss of vascular elasticity over time paves the way for basic functional changes. In addition, hypertrophy of the myocardium and blockages resulting from autonomic nervous system dysfunction are the most notable changes. Cardiovascular diseases such as cardiac hypertrophy, arrhythmia, and heart failure are the major problems as a result of these changes. Studies have also proven that the incidence of the diseases increases in parallel with age. It is thought that a better understanding of the consequences of the cardiac aging process will contribute to both promoting the healthy aging process and presenting more effective methods in the treatment of cardiovascular diseases for older individuals.