NATIONAL REVIEW COURSE. Cardiovascular System

Transcription

1 NATIONAL REVIEW COURSE Cardiovascular System I. Functions of Blood A. Transports gases (e.g. oxygen, carbon dioxide), nutrients to the tissues, waste products from the tissues, and hormones. B. Regulates the ph of the body, the amount of fluids in the tissues (by maintaining a proper osmotic pressure), and body temperature. C. Protects against pathogens and blood loss. II. Blood Constituents A. Blood plasma the liquid portion of unclotted blood. 1. Plasma proteins proteins found in the plasma; include albumins (help regulate blood pressure), globulins (help with transport and immunity), and fibrinogen (assists in blood clotting). B. Blood serum the liquid portion of clotted blood; plasma that has had the fibrinogen and other clotting factors removed so that the blood-clotting function is minimized. C. Formed elements the blood cells and platelets carried by the plasma. 1. Erythrocytes (red blood cells) biconcave, disk-shaped cells that do not contain nuclei; constitute approximately 40 to 50% of whole blood, depending on gender; have a life span of approximately 120 days. a. Hemoglobin an oxygen-carrying molecule made from iron; found in the erythrocytes. 2. Leukocytes (white blood cells) cells responsible for the body s defenses; contain nuclei and have varied life spans. 3. Thrombocytes (platelets) cell fragments without nuclei that assist in blood clotting; have a life span of approximately 8 to 10 days. III. Blood Clotting A. Hemostasis a three-step process of blood clotting; starts with muscle contraction in response in injury, proceeds to formation of a platelet plug, and ends with formation of a blood clot. 1. Muscle contraction smooth muscle of the blood vessel constricts when damaged or cut. 2. Platelet plug formation platelets in the region of damage become sticky and bind together with other platelets, blood cells, and the walls of the vessel. 3. Blood clot formation prothrombin is converted to thrombin, fibrinogen is converted into fibrin (a threadlike protein), and the fibrin threads form the clot. B. Animation: Hemostasis. * IV. Blood Typing A. Antigen a protein bound to the surface of a cell; gives the cell identity; examples include A, B, Rh, M. *

2 1. Type A antigen A on RBC. 2. Type B antigen B on RBC. 3. Type AB both antigen A and antigen B on RBC; known as universal recipient. 4. Type O neither antigen A nor antigen B on RBC; known as universal donor. B. Antibody (immunoglobulin) a component of the immune system found in the plasma, that attaches to a specific antigen on a cell; binds cells with other similar cells which prepares the cells for phagocytosis; the body produces antibodies only for foreign antigens. C. Blood transfusion the infusion of red blood cells into a living body; requires blood typing to match the recipient with an appropriate donor. V. Cardiac Muscle Tissue A. Found only in the heart, forming the bulk of the wall of each chamber. B. Also known as striated involuntary muscle. C. Contracts rhythmically and continuously to provide the pumping action needed to maintain a constant blood flow. D. Cardiac muscle fibers form strong, electrically coupled junctions (intercalated disks) with other fibers; individual cells also exhibit branching. E. Cardiac muscle fibers form a continuous, contractile band around the heart chambers that conducts a single impulse across a virtually continuous sarcolemma. VI. Location of the Heart A. Lies in the mediastinum, behind the body of the sternum between the points of attachment of ribs 2 through 6; approximately two thirds of its mass is to the left of the midline of the body and one third to the right. B. Posteriorly the heart rests on the bodies of thoracic vertebrae 5 through 8. C. Apex lies on the diaphragm, pointing to the left. D. Base lies just below the second rib. E. Animation: Heart Formation. * *

3 VII. Tissues of the Heart A. Endocardium the inner layer of the heart; composed of epithelial and connective tissues. B. Myocardium the thick middle layer of the heart; composed of cardiac muscle tissue that contracts regularly. C. Epicardium the outer covering or membrane around the heart; composed mostly of connective tissue. D. Pericardium the loose-fitting sac around the heart; composed of serous membranes. VIII. Heart Chambers A. Right atrium the upper-right chamber; receives deoxygenated blood from the body. B. Right ventricle the lower-right chamber; pumps blood to the lungs. C. Left atrium the upper-left chamber; receives oxygenated blood from the lungs. D. Left ventricle the lower-left chamber; pumps blood to the body. IX. Heart Valves A. Atrioventricular (AV) valves the valves that separate the atria and ventricles. 1. Tricuspid valve separates the right atrium and the right ventricle. 2. Bicuspid (mitral) valve separates the left atrium and the left ventricle.

4 B. Semilunar valves the valves that separate the ventricles from the blood vessels that attach to them. 1. Pulmonary semilunar valve separates the right ventricle from the pulmonary trunk. 2. Aortic semilunar valve separates the left ventricle from the aorta. X. Heart Sounds A. Systolic sound first sound called lubb ; believed to be caused primarily by the contraction of the ventricles and by vibrations of the closing AV valves. B. Diastolic sound second, short, sharp sound called dubb ; thought to be caused by vibrations of the closing of SL valves. C. Heart sounds have clinical significance because they give information about the functioning of the valves of the heart XI. Contraction of the Heart A. Cardiac cycle the cycle involving periods of systole (contraction of the myocardium) and diastole (relaxation of the myocardium) to fill and empty the chambers of the heart. B. Conduction pathway of the heart specialized strands of cardiac muscle tissue that coordinate the rhythmic contractions of the heart. 1. Sinoatrial (SA) node acts as the pacemaker of the heart; situated in the posterior wall of the right atrium. 2. Atrioventricular (AV) node the relay point for impulses coming from the sinoatrial node and initiates the contraction of the atria; situated toward the bottom of the interatrial septum. 3. Atrioventricular bundle (bundle of His) the short bundle of fibers at the top of the interventricular septum that relay the nervous impulse from the AV node to the left and right ventricles. 4. Bundle branches two branches that extend from the AV bundle and bring the impulse down the interventricular septum. 5. Purkinje fibers small fibers at the ends of the bundle branches that connect to and stimulate the contraction of the myocardium of the ventricles. C. Animation: Cardiac Conduction System. * D. Cardiac output the volume of blood pumped out of the heart per minute; calculated by multiplying the stroke volume of the heart by the heart rate. 1. Stroke volume the volume of blood pumped out of the left ventricle every time it contracts. 2. Heart rate the number of times the ventricles contract per minute. XII. Blood Flow Through the Heart A. Systemic circulation blood flow from the heart to the body and back to the heart. 1. Left ventricle aortic semilunar valve aorta arteries arterioles capillaries venules veins caval veins right atrium. *

5 B. Pulmonary circulation blood flow from the heart to the lungs and back to the heart. 2. Right ventricle pulmonary semilunar valve pulmonary trunk pulmonary arteries pulmonary arterioles pulmonary capillaries pulmonary venules pulmonary veins left atrium. C. Animation: Blood Flow Through the Human Heart. * XIII. Blood Supply of the Heart A. Coronary arteries blood vessels that take blood to the heart tissue; first branches of the aorta. B. Cardiac veins blood vessels that drain the heart tissue. C. Coronary sinus collects blood from the cardiac veins and empties into the right atrium. XIV. Blood Vessels A. Arteries blood vessels that carry blood away from the heart. 1. Arterioles small arteries. B. Veins blood vessels that carry blood toward the heart. 1. Venules small veins. C. Capillaries small blood vessels that connect arterioles and venules; where exchange of gases, nutrients, wastes, and hormones takes place. XV. Histology of Blood Vessels A. Tunica externa external layer of connective tissue. B. Tunica media middle layer make up of smooth muscle tissue. C. Tunica intima layer of squamous epithelial tissue (endothelium) that lines the lumen; the only layer present in capillaries. D. Lumen cavity in the vessel through which the blood flows. *

6 Diseases of the Cardiovascular System XVI. General Terminology A. Hypoxia deficiency of oxygen. B. Anoxia absence of oxygen. C. Ischemia a lack of blood supply; results in decreased oxygen and nutrient supply. D. Necrosis cell or tissue death. E. Thrombus a blood clot attached to the wall of a blood vessel. F. Embolus a free-floating blood clot, clump of fat, mass of cholesterol, mass of tissue, or even a mass of bacteria. G. Cyanosis bluish discoloration of the skin caused by a deficiency of oxygen in the blood. XVII. Disorders A. Hypertension high blood pressure ( 140 mmhg for systolic pressure and 90 mmhg for diastolic pressure). 1. Cause: exact cause is unknown, but many factors contribute (e.g. old age, obesity, smoking, genetic factors, stress). 2. Indications/Contraindications: obtain advice and approval of client s doctor before performing bodywork; massage is contraindicated in extreme cases because thrombus formation is possible; avoid deep tissue work or painful massage in all cases; soothing massage may reduce high blood pressure and associated stress.

7 3. Animation: Hypertension overview. * B. Hypotension low blood pressure (<100 mmhg for systolic pressure). 1. Causes: overall good heath; blood loss. 2. Indications/Contraindications: consult with client s doctor; be careful when the client sits up or stands after massage is completed. C. Anemia a decrease in the oxygen-carrying capacity of the blood; accompanied by dizziness, fatigue, nausea, lightheadedness, and pale coloration of the skin. 1. Causes: see following definitions of specific types of anemia. 2. Indications/Contraindications: avoid deep massage because extreme fluid movement or pressure on surface vessels may be harmful; massage should be light and soothing. 3. Sickle cell anemia a genetic condition causing malformed hemoglobin molecules; produces fragile sickle or crescent-shaped red blood cells that are easily destroyed; causes thickening of the blood, which strains the heart and reduces blood flow. 4. Hemorrhagic anemia anemia resulting from a loss of blood volume. 5. Hemolytic anemia anemia resulting from excessive destruction of red blood cells. 6. Iron deficiency anemia anemia resulting from decreased hemoglobin production; caused by a lack of dietary iron. 7. Aplastic anemia anemia in which the number of functioning stem cells in the bone marrow is decreased; results from drugs, chemicals, radiation, or cancer. 8. Pernicious anemia anemia resulting from deficiency or malabsorption of vitamin B 12. D. Leukemia a disease in which many immature and ineffective white blood cells are produced; classified according to the type of predominant WBCs, the severity of symptoms, and the total WBC count. 1. Cause: disease in which malignant stem cells develop in the bone marrow. 2. Indications/Contraindications: obtain approval of client s doctor before performing bodywork; all massage should be light because of the tendency for bleeding and bruising; energy work could be beneficial. E. Hemophilia characterized by the inability to form a blood clot because of a deficiency of blood-clotting factors. 1. Cause: sex-linked genetic disorder. 2. Indications/Contraindications: obtain advice and approval of client s doctor before performing bodywork; massage should be very light so as not to cause tissue damage or bruising; use universal precautions in case of bleeding; energy work can be beneficial. *

8 F. Shock a condition in which there is inadequate delivery of oxygenated blood to the tissues, particularly to the central nervous system; signs and symptoms include pale or bluish skin, overall weakness, rapid and faint pulse, restless and anxious behavior, severe thirst, nausea, dilated pupils, sweating, and shallow and rapid breathing. 1. Causes: see following definitions of specific types of shock. 2. Indications/Contraindications: massage is contraindicated; refer to first aid procedures. 3. Hypovolemic shock shock caused by a decrease in blood volume because of hemorrhage or excessive fluid loss. 4. Cardiogenic shock shock caused by inadequate pumping action of the heart; usually the result of myocardial infarction; leads to decreased blood pressure. 5. Septic shock shock caused by bacterial infection; results in localized vasodilation and increased blood vessel permeability, and thus decreased blood pressure. 6. Anaphylactic shock shock caused by systemic release of a large amount of histamine during an allergic response; results in widespread vasodilation and increased blood vessel permeability, and thus decreased blood pressure. G. Arrhythmia an abnormal or irregular heartbeat; often benign. 1. Causes: impulse variations coming into the sinoatrial node from the vagus nerve; electrolyte imbalances. 2. Indications/Contraindications: consult with client s doctor; an massage should be light and soothing. 3. Animation: Arrhythmias. * H. Pericarditis inflammation of the pericardium. 1. Causes: bacterial infection; calcium and fibrous deposits around the heart. 2. Indications/Contraindications: obtain approval of client s doctor before performing bodywork; the presence of infection is a contraindication to massage. I. Phlebitis inflammation of a vein; quite common; not very serious in superficial veins; more serious in deep veins. 1. Cause: unknown (most cases); injury; predisposing factors include obesity and lack of activity. 2. Indications/Contraindications: avoid affected area. J. Hemorrhoids a condition characterized by varicose veins of the rectum and anus. 1. Causes: increased pressure on the veins of the anus; pregnancy. 2. Indications/Contraindications: do not massage the surrounding gluteal and coccygeal areas. K. Coarctation of the aorta localized narrowing of the aorta; impedes blood flow. 1. Cause: congenital defect. *

9 2. Indications/Contraindications: consult with client s doctor. L. Aneurysm a localized bulge in the wall of an artery. 1. Cause: weakening in the arterial wall. 2. Indications/Contraindications: avoid the area where the aneurysm is located; avoid abdominal massage. M. Murmur sound heard when blood escapes through a valve of the heart. 1. Causes: leaky heart valve (congenital condition); previous infection of heart tissue. 2. Indications/Contraindications: many heart murmurs are benign, but consult with client s doctor to be sure. N. Myocardial infarction sudden insufficient blood supply to a segment of heart muscle; results in an area of necrotic cardiac muscle tissue; symptoms include angina, shortness of breath, and radiating pain. 1. Cause: usually atherosclerosis of the coronary arteries. 2. Indications/Contraindications: if client has symptoms of infarction, refer to doctor immediately. O. Angina pectoris pain in the chest and arm that may be described as dull, sharp, burning, or aching. 1. Cause: myocardial ischemia. 2. Indications/Contraindications: massage can overwork the heart, so obtain approval of client s doctor before performing bodywork; massage should be light and soothing; avoid endangerment areas and abdominal massage (which may cause increased pressure on the heart); client is best positioned supine with a cushion under the right hip to avoid pressure on the inferior vena cava. P. Varicose vein a vein that swells with accumulating blood; condition is usually permanent. 1. Cause: excessive pressure on the veins causing failure of the oneway valves. 2. Indications/Contraindications: avoid massage to directly on or distal to affected areas because clots that may form could be broken off into the general circulation; work done proximal to the area can be beneficial. Q. Arteriosclerosis a group of pathologic conditions characterized by thickening and hardening of the arteries; decreased blood flow to the brain and extremities may cause dizziness and headaches. 1. Atherosclerosis hardening and thickening of the arteries resulting from buildup of plaque made of cholesterol and lipids; decrease in elasticity causes narrowing of lumen, leading to decreased blood flow through the artery; eventually alters the function of the tissues. a. Causes: diabetes; obesity; steroid use; some hereditary metabolic disorders. b. Indications/Contraindications: obtain approval of client s doctor before performing bodywork; avoid localized

10 massage around the carotid artery; avoid deep tissue work; avoid head and neck region. c. Animation: Atherosclerosis. * R. Raynaud disease a condition characterized by peripheral vasoconstriction, most commonly in the digits; most common in women; symptoms include extreme cold, numbness, and pain in the digits; differential diagnoses include scleroderma, thoracic outlet syndrome, stress, and exposure to vibrating machinery. 1. Cause: unknown. 2. Indications/Contraindications: massage may increase circulation, reduce associated stress, and relax affected muscles. Sample Questions Which of the following is not a purpose of the blood? A. Transportation. B. Digestion. C. Protection. D. Regulation. Type O Rh-positive blood has: A. the A antigen, B antibody, and Rh antigen. B. the A and B antigens and the Rh antibody. C. the A and B antibodies and the Rh antigen. D. no antigens and the A, B, and Rh antibodies. Which valves in the heart produce the strong lubb sound? A. Atrioventricular valves. B. Semilunar valves. C. Atrioventricular and semilunar valves closing together. D. Atrioventricular and semilunar valves opening together. What substance in the blood carries oxygen to other cells of the body? A. Hemoglobin. B. Leukocytes. C. Plasma. D. Albumin. Which is the proper sequence of blood flow through the heart? A. Right ventricle, pulmonary semilunar valve, pulmonary trunk, pulmonary arteries. B. Superior vena cava, left atrium, tricuspid valve, left ventricle. C. Bicuspid valve, aorta, lungs, pulmonary veins. D. Right atrium, pulmonary semilunar valve, aorta, body. Which of the following is considered the pacemaker of the heart? A. Sinoatrial node. B. Atrioventricular node. C. Bundle of His. D. Purkinje fibers. *

11 Hardening of the arteries due to a buildup of plaque made of cholesterol and lipids is: A. heart block. B. atherosclerosis. C. heart murmur. D. varicosity. Which of the following conditions is characterized by pain in the chest that radiates down the left arm? A. Arrhythmia. B. Heart murmur. C. Phlebitis. D. Angina pectoris. When blood leaves the heart it goes through these vessels in order: A. arterioles, venules, capillaries, veins, arteries. B. arteries, arterioles, capillaries, venules, veins. C. arteries, capillaries, venules, veins, arterioles. D. arterioles, arteries, capillaries, veins. Once blood exits the right ventricle it goes to the: A. aorta. B. lungs. C. right atrium. D. muscles of the body. The deoxygenated blood from the body enters what part of the heart first? A. The left atrium. B. The left ventricle. C. The right atrium. D. The right ventricle. The vessel that takes blood from the heart to the lungs is called the: A. pulmonary vein. B. aorta. C. pulmonary artery. D. capillaries. A clot traveling through a blood vessel is called a/an: A. thrombus. B. embolus. C. infarction. D. phlebitis. When the heart is contracted, this correlates to which number in the blood pressure? A. The diastolic. B. The systolic. C. The bottom number. D. Both A and C are correct.

12 Another name for the sac around the heart is: A. periosteum. B. pleural fascia. C. myocardium. D. pericardium. The valve that separates the left atrium from the left ventricle is the: A. mitral. B. tricuspid. C. semilunar. D. Purkinje. Destruction of blood cells is called: A. hemoglobin. B. hemorrhage. C. hyperacusis. D. hemolysis. Which of the following are mechanisms for blood clotting? A. Platelet plug. B. Coagulation. C. Vascular spasm. D. All of the above are correct. When the diameter of the vascular lumen enlarges, it is called: A. vasoconstriction. B. vasodialation. C. myocardial infarction. D. endocardial fibrosis.