Which physiological changes in the cardiovascular system are related to the aging process?
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As people age, the heart tends to enlarge slightly, developing thicker walls and slightly larger chambers. The increase in size is mainly due to an increase in the size of individual heart muscle cells. Thicker walls also become stiffer, which does not allow the chambers to fill with as much blood before each ventricle pumps. The
age-related stiffening of the heart walls causes the left ventricle to not fill as well and can sometimes lead to heart failure
Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more
During rest, the older
heart functions in almost the same way as a younger heart, except the heart rate (number of times the heart beats within a minute) is slightly lower. Also, during exercise, older people's heart rate does not increase as much as in younger people. The walls of the arteries and arterioles become thicker, and the space within the arteries expands slightly. Elastic tissue within the walls of the arteries and arterioles is lost. Together, these changes make the vessels stiffer and less
resilient (see figure
.
Since the arteries and arterioles are less elastic, blood pressure cannot adjust quickly when people stand, and older people are at risk for dizziness or in some cases fainting when they stand up suddenly. CLICK HERE FOR THE PROFESSIONAL VERSION Copyright © 2022 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved. Abstract and IntroductionWith aging there are changes in the cardiovascular system, which result in alterations in cardiovascular physiology. The changes in cardiovascular physiology must be differentiated from the effects of pathology, such as coronary artery disease, that occur with increasing frequency as age increases. The changes with age occur in everyone but not necessarily at the same rate, therefore accounting for the difference seen in some people between chronologic age and physiologic age. The changes in the cardiovascular system associated with aging are a decrease in elasticity and an increase in stiffness of the arterial system. This results in increased afterload on the left ventricle, an increase in systolic blood pressure, and left ventricular hypertrophy, as well as other changes in the left ventricular wall that prolong relaxation of the left ventricle in diastole. There is a dropout of atrial pacemaker cells resulting in a decrease in intrinsic heart rate. With fibrosis of the cardiac skeleton there is calcification at the base of the aortic valve and damage to the His bundle as it perforates the right fibrous trigone. Finally there is decreased responsiveness to The process of aging is a continuum progressing throughout the individual's life. Unlike pathologic conditions, the aging process affects all individuals. It is a process that is genetically programmed but modified by environmental influences, so the rate of aging can vary widely among people. Therefore, physiologic aging in any given individual may occur more rapidly or more slowly than the chronologic age, giving rise to people who are "old" at age 60 and others who are "young" at age 75. The status of physical conditioning of the individual can radically affect the measurements of cardiovascular function in the elderly and changes in physical activity can profoundly change cardiovascular function.[1] Physiologic aging is characterized by gradual loss in function in many organ systems. With aging there is also an increasing incidence of diseases such as coronary artery disease (CAD), cerebrovascular disease, renal, and pulmonary disease that can accelerate the loss of function. A major problem in human beings in measuring the effect of aging on cardiovascular physiology is that of eliminating the effects of latent disease in the population studied. This is illustrated by the prevalence of CAD in autopsy studies where over 60% of the patients dying at age 60 or older had at least one coronary artery that had a 75% or greater occlusion.[2] Since other studies find that about 20% of patients older than 80 years of age have clinically manifest CAD, the majority of older people with significant obstructive CAD are asymptomatic.[3] Therefore when evaluating the effect of age on cardiovascular physiology in a population of apparently healthy elderly people, those with latent CAD must be eliminated. In many studies reported in "healthy" elderly populations this has not been done and may account for discrepancies among studies reported on the effects of aging on cardiovascular function. Which is a physiological change of the cardiovascular system associated with aging?The changes in the cardiovascular system associated with aging are a decrease in elasticity and an increase in stiffness of the arterial system.
Which physiological changes in the cardiovascular system are related to the aging process quizlet?Age-related changes associated with the cardiovascular system include decreased cardiac output, increased blood pressure, decreased compliance of the heart muscle, and thickening of the heart valves.
Which physiological changes is are associated with aging?Abstract. Physiological changes occur with aging in all organ systems. The cardiac output decreases, blood pressure increases and arteriosclerosis develops. The lungs show impaired gas exchange, a decrease in vital capacity and slower expiratory flow rates.
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