CHAPTER 10 Cardiovascular System Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cardiovascular System Overview • Responsibilities of cardiovascular system – Pumping blood to the body tissues and cells – Supplying oxygen and nutrients to tissues and cells – Removing carbon dioxide and other waste products of metabolism from tissues and cells Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cardiovascular System • Heart – Center of the circulatory system – Enclosed by pericardium • Parietal pericardium • Visceral pericardium • Pericardial cavity Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cardiovascular System • Heart – Three layers of the heart • Epicardium • Myocardium • Endocardium Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Heart • Chambers – Right atrium and left atrium • Upper chambers • Receiving chambers – Right ventricle and left ventricle • Lower chambers • Pumping chambers Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Heart • Partitions – Interatrial septum • Separates right and left sides of atria – Interventricular septum • Separates right and left sides of ventricles Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question Which layer of the heart is required for muscle contraction? a. b. c. d. epicardium endocardium myocardium pericardium Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Circulation Through the Heart • Deoxygenated blood – Enters right atrium from superior vena cava • Brings blood from head, thorax, upper limbs, and abdominal viscera – Also enters right atrium from inferior vena cava • Brings blood from the trunk, lower limbs, and abdominal viscera Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Circulation Through the Heart • Deoxygenated blood travels: – From right atrium through tricuspid valve into right ventricle – From right ventricle through pulmonary valve into right and left pulmonary arteries Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Circulation Through the Heart • Deoxygenated blood travels: – From pulmonary arteries to lungs • Pulmonary arteries are the only arteries that carry deoxygenated blood • Exchange of gases takes place in the lungs Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Circulation Through the Heart • Oxygenated blood – Enters left atrium from lungs via pulmonary veins • Pulmonary veins are only veins in body that carry oxygenated blood – From left atrium through mitral valve into left ventricle – From left ventricle through aortic valve into aorta – From aorta to arteries to each body part and region Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Circulation Through the Heart • Pulmonary circulation – Circulation of blood from the heart to the lungs for oxygenation and back to the heart • Systemic circulation – Circulation of blood from the heart to all parts of the body and back to the heart Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Circulation Through the Heart • Coronary arteries – Arise from aorta near its origin at left ventricle – Supply blood to heart muscle – Heart muscle has a greater need for oxygen and nutrients • Heart uses approximately 3 times more oxygen than other body organs Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Circulation Through the Heart Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question True or False: Getting oxygenated blood to the lungs is vital to other body systems. Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Conduction System of the Heart • Sinoatrial node (SA node) sets rhythm for entire heart – SA node = pacemaker of the heart – Impulse from SA node causes atria to contract • Impulse travels from SA node to atrioventricular node (AV node) Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Conduction System of the Heart • Impulse from AV node travels to ventricles through bundle of His – Bundle of His divides into right and left bundle branches • Bundle branches terminate in Purkinje fibers – Purkinje fibers fan out into the muscles of the ventricles – Purkinje fibers cause ventricles to contract Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Conduction System of the Heart Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Supporting Blood Vessels • Arteries – Large, thick-walled vessels – Carry blood away from the heart • Arterioles – Thinner walls than arteries – Transport blood on to capillaries Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Supporting Blood Vessels • Capillaries – Extremely thin walls = single layer – Allow for exchange of materials between blood and tissue fluid surrounding body cells Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Supporting Blood Vessels • Venules – Smallest veins – Collect deoxygenated blood from cells for transport back to heart • Veins – Thinner walls than arteries – Thicker walls than capillaries – Transport blood from venules to heart Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question In looking at the diagram of the heart, what is unique about the pulmonary arteries and veins? a. Nothing else uses “pulmonary” in the name. b. The arteries carry deoxygenated blood and veins carry oxygenated blood. c. Each is connected to the opposite lung. d. There is nothing unique about them. Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cardiac Cycle • One cardiac cycle = one complete heartbeat • Diastole – Relaxation phase of heartbeat – Ventricles relax and fill with blood • Systole – Contraction phase of heartbeat – Ventricles contract and force blood out of heart Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Blood Pressure • Blood pressure – Pressure exerted by blood on walls of arteries • Systolic pressure – Maximum pressure reached within the ventricles Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Blood Pressure • Diastolic pressure – Minimum pressure reached within the ventricles • Sphygmomanometer = blood pressure cuff – Used to measure blood pressure Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Common Signs and Symptoms • Symptoms that may indicate cardiovascular problems Anorexia Anxiety Bradycardia Chest pain Cyanosis Dyspnea Edema Fatigue Fever Headache Nausea Pallor Palpitation Sweat Tachycardia Vomiting ---------- --------------- --------- Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Weakness PATHOLOGICAL CONDITIONS Cardiovascular System Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Angina Pectoris • Pronounced – (an-JYE-nah PECK-tor-is) – (AN-jin-nah PECK-tor-is) • Defined – Severe pain and constriction about the heart, usually radiating to left shoulder and down left arm • Creates feeling of pressure in anterior chest Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cardiac Tamponade • Pronounced – (KAR-dee-ak TAM-poh-nod) • Defined – Compression of the heart caused by accumulation of blood or other fluid within the pericardial sac • Accumulation of fluid in pericardial cavity prevents ventricles from adequately filling or pumping blood Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Cardiomyopathy • Pronounced – (kar-dee-oh-my-OP-ah-thee) • Defined – Disease of the heart muscle itself, primarily affecting pumping ability of the heart • Noninflammatory disease of the heart • Results in enlargement of the heart and dysfunction of the ventricles of the heart Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question True or False: If a patient has angina pectoris, the first concern is a heart attack. Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Congestive Heart Failure • Pronounced – (kon-JESS-tiv heart failure) • Defined – Condition in which pumping ability of heart is progressively impaired to the point that it no longer meets bodily needs Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Congestive Heart Failure • Left-sided cardiac failure – Left ventricle unable to pump blood that enters from the lungs Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Congestive Heart Failure • Left-sided cardiac failure – Characteristics: • • • • • • Dyspnea Moist sounding cough Fatigue Tachycardia Restlessness Anxiety Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Congestive Heart Failure • Right-sided cardiac failure – Right side of heart cannot empty blood received from venous circulation – Characteristics: • Edema of lower extremities (pitting edema) • Weight gain • Enlargement of liver (hepatomegaly) Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Congestive Heart Failure • Right-sided cardiac failure – Characteristics: • • • • • Distended neck veins Ascites Anorexia Nocturia Weakness Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Coronary Artery Disease • Pronounced – (KOR-oh-nah-ree AR-ter-ee dih-ZEEZ) • Defined – Narrowing of the coronary arteries to the extent that adequate blood supply to the myocardium is prevented Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Coronary Artery Disease • Treatments for occluded coronary arteries – – – – Medications Percutaneous transluminal coronary angioplasty (PTCA) Directional coronary atherectomy Coronary bypass surgery = Coronary artery bypass graft (CABG) Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Endocarditis • Pronounced – (en-doh-car-DYE-tis) • Defined – Inflammation of the membrane lining of the valves and chambers of the heart • Caused by direct invasion of bacteria or other organisms • Leads to deformity of valve cusps Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question In coronary artery bypass grafting, what large vessel is the main source of the new blood supply? a. b. c. d. vena cava pulmonary artery brachiocephalic artery aorta Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Hypertensive Heart Disease • Pronounced – (high-per-TEN-siv heart dih-ZEEZ) • Defined – Heart disease as a result of long-term hypertension • Heart must work against increased resistance due to increased pressure in the arteries Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Mitral Valve Prolapse • Pronounced – (MY-tral valve proh-LAPS) • Defined – Drooping of one or both cusps of the mitral valve back into the left atrium during ventricular systole • Results in incomplete closure of the valve and mitral insufficiency Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Myocardial Infarction • Pronounced – (my-oh-KAR-dee-al in-FARK-shun) • Defined – Condition caused by occlusion of one or more of the coronary arteries = destruction of myocardial tissue – Heart attack • Life-threatening condition Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Myocarditis • Pronounced – (my-oh-kar-DYE-tis) • Defined – Inflammation of the myocardium • May be viral or bacterial infection • May be result of systemic disease • May be caused by fungal infections, serum sickness, or chemical agent Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Pericarditis • Pronounced – (per-ih-kar-DYE-tis) • Defined – Inflammation of the pericardium (saclike membrane) that covers the heart muscle • May be acute or chronic Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Rheumatic Fever • Pronounced – (roo-MAT-ik fever) • Defined – Inflammatory disease that may develop as a delayed reaction to insufficiently treated Group A beta-hemolytic streptococcal infection of the upper respiratory tract Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question True or False: Another term for the backflow of blood into the left atrium is regurgitation. Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. PATHOLOGICAL CONDITIONS Blood Vessels Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Aneurysm • Pronounced – (AN-yoo-rizm) • Defined – Localized dilatation of an artery formed at a weak point in the vessel wall • Weakened area balloons out with each pulsation of artery Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Arteriosclerosis • Pronounced – (ar-tee-ree-oh-skleh-ROH-sis) • Defined – Arterial condition in which there is thickening, hardening, and loss of elasticity of the walls of arteries (hardening of the arteries) • Results in decreased blood supply, especially to lower extremities and cerebrum Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Hypertension • Pronounced – (high-per-TEN-shun) • Defined – Condition in which the patient has a higher blood pressure than judged to be normal • Blood pressure persistently exceeds 140/90 mmHg Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Hypertension • Essential hypertension – Accounts for 90 percent of all hypertension – No single known cause • Secondary hypertension – Due to underlying cause • Malignant hypertension – Severe and rapidly progressive – Diastolic pressure higher than 120 mmHg Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Peripheral Arterial Occlusive Disease • Pronounced – (per-IF-er-al ar-TEE-ree-al oh-KLOO-siv dih-ZEEZ) • Defined – Obstruction of the arteries in the extremities (predominantly the legs) • Leading cause = atherosclerosis • Classic symptom = intermittent claudication Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Raynaud’s Phenomenon • Pronounced – (ray-NOZ feh-NOM-eh-non) • Defined – Intermittent attacks of vasoconstriction of the arterioles • Causes pallor of the fingers or toes, followed by cyanosis, then redness before returning to normal color (white-blue-red) • Initiated by exposure to cold or emotional disturbance Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question What would be the term for surgical removal of an aneurysm? a. b. c. d. aneurysmectomy aneurysmoectomy aneurysmotomy aneurysmoplasty Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Thrombophlebitis • Pronounced – (throm-boh-fleh-BYE-tis) • Defined – Inflammation of a vein associated with the formation of a thrombus (clot) • Usually occurs in an extremity, most frequently a leg Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Thrombophlebitis • Superficial thrombophlebitis – Usually obvious – Accompanied by cordlike or thready appearance to the vessel • Deep vein thrombosis (DVT) – Occurs primarily in lower legs, thighs, and pelvic area – Characterized by aching or cramping pain in legs Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Varicose Veins • Pronounced – (VAIR-ih-kohs veins) • Defined – Enlarged, superficial veins – Twisted, dilated veins with incompetent valves Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Varicose Veins • Treatment – Rest and elevation of affected extremity – Use of elastic stockings – Sclerotherapy • Injection of a chemical irritant into the varicosed vein (sclerosing agent) – Vein stripping Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Varicose Veins Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Venous Insufficiency • Pronounced – (VEE-nuss in-soo-FISH-in-see) • Defined – An abnormal circulatory condition characterized by decreased return of venous blood from the legs to the trunk of the body Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question True or False: Venous insufficiency is not as severe as varicose veins. Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. PATHOLOGICAL CONDITIONS Congenital Heart Diseases Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Coarctation of the Aorta • Pronounced – (koh-ark-TAY-shun of the aorta) • Defined – Congenital heart defect characterized by a localized narrowing of the aorta • Results in increased blood pressure in upper extremities and decreased blood pressure in lower extremities Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Patent Ductus Arteriosus • Pronounced – (PAY-tent DUCK-tus ar-tee-ree-OH-sis) • Defined – Abnormal opening between the pulmonary artery and the aorta caused by failure of fetal ductus arteriosus to close after birth • Defect seen primarily in premature infants Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Tetralogy of Fallot • Pronounced – (teh-TRALL-oh-jee of fal-LOH) • Defined – Congenital heart anomaly that consists of four defects • • • • Pulmonary stenosis Interventricular septal defect Dextraposition of aorta (shifts to the right) Hypertrophy of right ventricle Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Transposition of the Great Vessels • Pronounced – (tranz-poh-ZIH-shun of the great vessels) • Defined – Condition in which the two major arteries of the heart are reversed in position • Results in two noncommunicating circulatory systems Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question Which of the congenital abnormalities mentioned require surgical correction? a. b. c. d. tetralogy of Fallot patent ductus arteriosus coarctation of the aorta all of them Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. PATHOLOGICAL CONDITIONS Arrhythmias Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Atrial Flutter • Pronounced – (AY-tree-al flutter) • Defined – Condition in which the contractions of the atria become extremely rapid, at the rate of between 250 to 350 beats per minute Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Fibrillation (Atrial Fibrillation) • Pronounced – (atrial fih-brill-AY-shun) • Defined – Extremely rapid, incomplete contractions of the atria resulting in disorganized and uncoordinated twitching of the atria • Rate of contractions may be as high as 350 to 600 beats per minute Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Fibrillation (Ventricular Fibrillation) • Pronounced – (ven-TRIK-yoo-lar fih-brill-AY-shun) Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Fibrillation (Ventricular Fibrillation) • Defined – Rapid, tremulous (quivering like a bowl of Jell-O) and ineffectual contractions of the ventricles • • • • • No audible heartbeat No palpable pulse No respiration No blood circulation If prolonged, will lead to cardiac arrest Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Heart Block (AV) • Pronounced – (Heart Block) • Defined – An interference with the normal conduction of electric impulses that control activity of the heart muscle Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Ventricular Tachycardia • Pronounced – (ven-TRIK-yoo-lar tak-ee-KAR-dee-ah) • Defined – Condition in which the ventricles of the heart beat at a rate greater than 100 beats per minute – Characterized by 3 or more consecutive premature ventricular contractions (PVCs) – Also known as V-tach Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question True or False: Ventricular fibrillation must be corrected within 3 to 4 minutes, or the result is death. Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. DIAGNOSTIC TECHNIQUES, TREATMENTS, AND PROCEDURES Cardiovascular System Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Angiography – X-ray visualization of internal anatomy of heart and blood vessels after introducing a radiopaque substance (contrast medium) – Promotes imaging of internal structures that are otherwise difficult to see on X-ray film • Substance is injected into an artery or a vein Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Cardiac catheterization – Diagnostic procedure in which a catheter is introduced into a large vein or artery, usually of an arm or a leg, and is then threaded through the circulatory system to the heart • Used to obtain detailed information about the structure and function of the heart chambers, valves, and the great vessels Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Cardiac enzymes test – Tests performed on samples of blood obtained by venipuncture to determine the presence of damage to the myocardial muscle • (CAT) Computed axial tomography – Diagnostic X-ray technique that uses ionizing radiation to produce a cross-sectional image of the body • Often used to detect aneurysms of the aorta Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Echocardiography – Diagnostic procedure for studying the structure and motion of the heart • Useful in evaluating structural and functional changes in a variety of heart disorders • Electrocardiogram (EKG, ECG) – Graphic record of the electrical action of the heart as reflected from various angles to the surface of the skin Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Exercise stress testing – Means of assessing cardiac function by subjecting the patient to carefully controlled amounts of physical stress, for example, using the treadmill Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Holter monitoring – Small, portable monitoring device that makes prolonged electrocardiograph recordings on a portable tape recorder • Continuous EKG (ambulatory EKG) is recorded on a magnetic tape recording while the patient conducts normal daily activities Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question A patient with angina pectoris has an abnormal EKG and elevated cardiac enzymes. __________________ is then performed to determine the extent of cardiovascular disease. a. b. c. d. Exercise stress testing Cardiac catheterization Holter monitoring Computed axial tomography Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Event monitor – Similar to the Holter monitor in that it also records the electrical activity of the heart while patient goes about usual daily activities – Can be used for a longer period of time than a Holter monitor • Usually a month Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Implantable cardioverter defibrillator (ICD) – Small, lightweight, electronic device placed under the skin or muscle in either the chest or abdomen to monitor the heart’s rhythm – If abnormal rhythm occurs, the ICD helps return the heart to its normal rhythm Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Magnetic resonance imaging (MRI) – Use of strong magnetic field and radiofrequency waves to produce imaging that is valuable in providing images of the heart, large blood vessels, brain, and soft tissue • Used to examine the aorta, to detect masses or possible tumors, and pericardial disease • Can also show the flowing of blood and the beating of the heart Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Positron emission tomography (PET) – Computerized X-ray technique that uses radioactive substances to examine the blood flow and the metabolic activity of various body structures, such as the heart and blood vessels • Patient is given doses of strong radioactive tracers by injection or inhalation • Radiation emitted is measured by the PET camera Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Diagnostic Techniques, Treatments, and Procedures • Serum lipid – Test that measures the amount of fatty substances (cholesterol, triglycerides, and lipoproteins) in a sample of blood obtained by venipuncture • Thallium stress – Combination of exercise stress testing with thallium imaging to assess changes in coronary blood flow during exercise Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Question True or False: The PET scanner is helpful in detecting coronary artery disease, which is less invasive than cardiac catheterization. Copyright © 2011 Delmar, Cengage Learning. ALL RIGHTS RESERVED.