Age is a major risk factor for cardiovascular disease including heart disease. After menopause, the incidence of heart disease in women rises and eventually virtually mirrors heart disease rates in men. Though heart disease once was regarded as a "man's disease," it is the leading cause of death in both men and women.
Effect of Age on heart
It is known that certain changes to the heart even in the absence of disease are common as people age. 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.
This includes:
a thickening and stiffening of the heart walls (particularly, the left ventricle) which leads to a reduced ability of the heart (left ventricle) to relax and fill adequately between beats (diastolic dysfunction). This reduced or slowed filling of the heart can further lead to inefficient pumping during periods of increased exertion, contributing to fatigue and exercise intolerance.
Another age-related change includes enlargement of the left atrium, the upper chamber of the heart, which can lead to atrial fibrillation (unorganized heart rhythm originating from the upper heart chambers). Slowing of the pacemaker cells of the atria, another consequence of normal aging, can also lead to rhythm problems.
Arteries also change with age. They become stiffer, with thicker walls and a subsequent reduced ability to expand properly as blood pumps through them. Because arteries and arterioles become less elastic as people age, they cannot relax as quickly during the rhythmic pumping of the heart. As a result, blood pressure increases more when the heart contracts (during systole)—sometimes above normal—than it does in younger people. Abnormally high blood pressure during systole with normal blood pressure during diastole is very common among older people; this disorder is called isolated systolic hypertension.
As the heart ages, it becomes less able to respond rapidly to chemical messages from the brain. Researchers do not know exactly why the heart does not respond as fast to messages to speed up and adjust to increased activity. The result is the body cannot exercise as long or as intensely as before. This shows up as shortness of breath -- a sign that oxygen-rich blood is not moving fast enough through the body because the lungs are trying to breath in more oxygen.
The heart rate of an older person while sitting is slower than a younger person (but the same when lying down). It is thought that this slower rate is from a decline in the heart-brain communication because fibrous tissue and fatty deposits have built up on the on nerves connecting the heart and brain. To compensate, the heart increases the volume of blood in circulation by raising the diastolic blood pressure.
The Heart Can't Squeeze as Tightly: Because of the increase in diastolic blood pressure, the heart also stretches larger each beat, giving a stronger pump in order to have a stronger contraction to pump the excess blood volume (called the Frank-Starling mechanism). But because of the greater diastolic pressure, the heart can't squeeze as tightly.
The heart of a healthy 70-year-old has 30 percent fewer cells than a 20-year-old's heart. When heart cells die, the other cells must stretch and grow to stay connected. An older person's heart cells may be up to 40 percent larger than a younger persons.
While there is a great deal known about age-related changes that occur in the arteries and the subsequent changes in cardiac function, new research is underway that will likely enable us to learn how to slow down or even reverse some of these changes. What research has revealed and continues to show is that many of the changes within the heart have as much to do with lifestyle as age, underscoring the importance of adopting and maintaining a healthy lifestyle.
Effect of Age on heart
It is known that certain changes to the heart even in the absence of disease are common as people age. 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.
This includes:
a thickening and stiffening of the heart walls (particularly, the left ventricle) which leads to a reduced ability of the heart (left ventricle) to relax and fill adequately between beats (diastolic dysfunction). This reduced or slowed filling of the heart can further lead to inefficient pumping during periods of increased exertion, contributing to fatigue and exercise intolerance.
Another age-related change includes enlargement of the left atrium, the upper chamber of the heart, which can lead to atrial fibrillation (unorganized heart rhythm originating from the upper heart chambers). Slowing of the pacemaker cells of the atria, another consequence of normal aging, can also lead to rhythm problems.
Arteries also change with age. They become stiffer, with thicker walls and a subsequent reduced ability to expand properly as blood pumps through them. Because arteries and arterioles become less elastic as people age, they cannot relax as quickly during the rhythmic pumping of the heart. As a result, blood pressure increases more when the heart contracts (during systole)—sometimes above normal—than it does in younger people. Abnormally high blood pressure during systole with normal blood pressure during diastole is very common among older people; this disorder is called isolated systolic hypertension.
As the heart ages, it becomes less able to respond rapidly to chemical messages from the brain. Researchers do not know exactly why the heart does not respond as fast to messages to speed up and adjust to increased activity. The result is the body cannot exercise as long or as intensely as before. This shows up as shortness of breath -- a sign that oxygen-rich blood is not moving fast enough through the body because the lungs are trying to breath in more oxygen.
The heart rate of an older person while sitting is slower than a younger person (but the same when lying down). It is thought that this slower rate is from a decline in the heart-brain communication because fibrous tissue and fatty deposits have built up on the on nerves connecting the heart and brain. To compensate, the heart increases the volume of blood in circulation by raising the diastolic blood pressure.
The Heart Can't Squeeze as Tightly: Because of the increase in diastolic blood pressure, the heart also stretches larger each beat, giving a stronger pump in order to have a stronger contraction to pump the excess blood volume (called the Frank-Starling mechanism). But because of the greater diastolic pressure, the heart can't squeeze as tightly.
The heart of a healthy 70-year-old has 30 percent fewer cells than a 20-year-old's heart. When heart cells die, the other cells must stretch and grow to stay connected. An older person's heart cells may be up to 40 percent larger than a younger persons.
While there is a great deal known about age-related changes that occur in the arteries and the subsequent changes in cardiac function, new research is underway that will likely enable us to learn how to slow down or even reverse some of these changes. What research has revealed and continues to show is that many of the changes within the heart have as much to do with lifestyle as age, underscoring the importance of adopting and maintaining a healthy lifestyle.
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