Heart and arterial aging

Aging is the dominant risk factor for cardiovascular disease, and is linked to the age-associated changes to the structure and function of the heart and arteries. Age-associated changes occur in everyone but not necessarily at the same rate or to the same extent, and this may account for the difference noted in the development of cardiovascular disease between individuals of the same chronological age. Age-associated changes in cardiovascular physiology must be differentiated from the effects of pathology, such as coronary artery disease, which occur with increasing frequency as age increases to gain an understanding of normative aging. Prominent age-associated changes in the cardiovascular system include arterial remodeling, an increase in arterial stiffness, and an impaired endothelial vasoreactivity. This results in an increased afterload (including an increase in aortic and brachial pressures) on the left ventricle resulting in left ventricular wall thickening, and prolonged relaxation of the left ventricle in diastole. During stress there is also a decreased responsiveness to b-adrenergic receptor stimulation in the context of increased circulating catecholamines. These changes not only ultimately impair the ability of the cardiovascular system to respond to times of stress (exercise, illness, and mental stress) in older individuals, but also set the stage for the development of cardiovascular diseases in the elderly. Those individuals who maintain an physically active lifestyle, or who partake in exercise training later in life, however, can either ameliorate or delay some, but not all, of the cardiovascular alterations that accompany advancing age.