Age-Related Changes that Occur in the Cardiovascular System
ITT Technical Institute
As the heart ages it goes through changes such as thickening of the walls, slowing heart rate, decrease in maximum heart rate, loss of efficiency in pumping. The layers of the heart include the pericardium, epicardium, myocardium, and endocardium. The pericardium is the membrane that protects; it is a sac that the heart sits in and has a layer of fluid between for shock and absorption. The epicardium is the first layer of the heart. The myocardium is the second layer of the heart where the walls are not in contact with blood and are also the parts that contract. The endocardium is where the blood makes direct contact and is the last layer of the heart.
There are four chambers in the heart, two atria and two ventricles. The atria are the upper receiving chambers and the ventricles are the lower pumping chambers. The right side of the heart contains deoxygenated blood and the left carries oxygenated blood. The right atrium receives blood from three veins, superior vena cava, inferior vena cava, and coronary sinus. The right ventricle forms the most outer surface of the heart. The left atrium receives blood from the lungs through four pulmonary veins. The left ventricle is the thickest chamber in the whole heart and forms the apex (bottom) of the heart.
The flow of blood begins in the right atrium where it is deoxygenated. From there it goes to the tricuspid valve, right ventricle, pulmonary valve, pulmonary trunk and arteries, pulmonary capillaries (where the blood loses carbon dioxide and gains oxygen), pulmonary veins, left atrium, bicuspid valve, left ventricle, aortic valve, aorta and systemic arteries, systemic capillaries (where the blood loses oxygen and gains carbon dioxide), super vena cava, inferior vena cava, and coronary sinus, back to the right atrium.
Regulation of the heart rate is controlled by several things....