Language of MED chapter 11 PDF

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Don Lehman...

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Language of Medicine

Chapter 11: Cardiovascular System Introduction: -

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Cardiovascular system o Delivers oxygen and nutrients to cells of the body o Heart o Blood Vessels Blood Vessels and the circulation of Blood o Arteries  Lead away from the heart  Thick walled  Small arteries are called Arterioles o Veins  Lead toward the heart  Thinner walled vessels  Small veins are called Venules o Capillaries  Smallest Vessels  Point of exchange for oxygen and nutrients into body cells and waste products coming from body cells Combining Forms and Terminology o o o o o o

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Angi/o Cardi/o Coron/o Phleb/o Rrhythm/o Thromb/o

= Vessel = Heart = Heart = Vein = rhythm = clot

Note: o Pulmonary artery carrying O2 – poor blood o Pulmonary vein carrying O2- rich blood Major Vessels o Pulse points  The pulse is the beat of the heart that can be felt through the walls of the arteries Major Valves of the Heart o Tricuspid Valve  Between right atrium and right ventricle o Pulmonary Valve:  Between right ventricle and pulmonary artery

Mitral Valve  Between left atrium and the left ventricle o Aortic Valve  Between left ventricle and aorta Anatomy of the Heart o Myocardium  Cardiac muscle  Middle muscular layer o Endocardium  Lines the interior of the heart o Pericardium  Membranous sac that surrounds the outside of the heart  Visceral Pericardium  Parietal Pericardium Heartbeat and Heart Sounds o Heart Rate (HR) the speed of the heartbeat o Two phases of the heartbeat  Diastole:  Relaxation  Tricuspid and mitral open  Pulmonary and aortic closed  Systole:  Contraction  Tricuspid and mitral closed  Pulmonary and aortic open o Systole:  Cardiac cycle 70-80 beats per minute (bpm)  The hearts pumps 3 ounces of blood with each contraction o Total blood volume is about 7 L  2000 gallons a day pumped o The heart pumps the equivalent of >1,000 total blood volumes each day Heart Sounds o Closure of valves associated with sounds “lubb-dubb, lubb-dubb” o Lubb (S1)  Closure of the Tricuspid and mitral valve at the beginning of the systole o Dubb (S2)  Closure of the aortic and pulmonary valves at the end of systole o Murmur;  Abnormal heart sound caused by improper valve closure o Auscultation: Conduction System of the Heart o Pacemaker of the heart o Excitation wave reaches a bundle of specialized fibers called the atrioventricular bundle (bundle of his) o

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Conduction myofibers that extend to ventricle walls and stimulate them to contract, beginning systole Electrocardiogram (EKG) o The record produced by electrocardiography o P wave:  Spread of excitation wave over the atria just before the contraction o QRS wave:  Spread of excitation wave over the ventricles as the ventricles contract o T wave:  Electrical recovery and relaxation of ventricles Blood Pressure o The force that blood exerts on arterial walls  Hypertension  Blood pressure greater than 140/90 mm Hg o Measured using sphygmomanometer  Sphygm/o = pulse  Man/o = pressure  -meter= measuring instrument o Expressed as a fraction:  Systolic pressure / Diastolic pressure  E.g., 120/80 mm Hg Pathology: The heart and blood vessels o Cardiovascular Disease  Coronary artery disease  Congenital Defects  Cardiac insufficiency  Heart attack  Heart valve problems  Ischemic stroke  Arrhythmia  Any condition (-ia) of deviation (dys-) from the normal rhythmic pattern of the heartbeat o Arrhythmias or dysrhythmias  Bradycardia  A slowing (brady-) of the heart’s (cardi/o) normal rate  Cardiac pacemaker  Tachycardia  An increase in the heart rate  Tachy- = fast  Flutter  A type of dysrhythmia characterized by rapid, but regular, contractions of the atria  May reach 300 bpm  Fibrillation 

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A disturbance of the heart’s rhythm during which very rapid, disorganized, and ineffectual contractions of the atria or ventricles occur  >350 bpm Normal fetal circulation Circulatory changes at birth Congenital heart disease  Congenital refers to structural or functional abnormalities of the heart that are present from birth  Coarctation (narrowing) of the aorta  A type of congenital abnormality characterized by a narrowing of an artery  Patent ductus arteriosus  Oxygenated blood can flow from the aorta into the pulmonary artery through a small passageway or duct o Ductus arteriosus  Normally closes after birth  Fetal connection between pulmonary vein and aorta does not close  Septal defects:  Atrial septal defect  Ventricular septal defect Congestive Heart failure  Diagnosis of CHf:  Check kidney function  Test for brain natriuretic peptide (BNP), aka B-type natriuretic peptide  Treatment:  Life style changes  Diuretics and other medications  Left ventricular assist device in end-stage disease  Cardiac Arrest  Aka. Cardiopulmonary arrest or circulatory arrest o Sudden cessation of the heart’s activity  Causes o Coronary heart disease o Drugs  Treatment o Cardiopulmonary resuscitation Coronary artery disease  Atherosclerosis:  Cholesterol  Thrombotic occlusion o The blocking of a coronary artery by a blood clot  Ischemia o Blood flow is decreased  Necrosis 

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o Myocardial tissue death Acute coronary syndromes (ACSs)  Consequences caused by myocardial ischemia  Myocardial infarction  Unstable angina: chest pain at rest  Diagnosis aided by angiography Clinical Procedures: Treatment o Cardioversion (Defibrillation)  Drug therapies for CAD: aspirin, coumadin, Plavix, statins  Nitrates (nitroglycerin):  sublingual  Beta-blockers:  Inhibit β-adrenergic response  ACE inhibitors:  Inhibit angiotensin II activity  Calcium channel blockers:  Decrease heart muscle contraction o Surgical therapies for CAD  Coronary artery bypass grafting  Percutaneous coronary intervention  Transmyocardial laser revascularization o Coronary artery bypass graft surgery  Bypass veins can come from leg or chest o Percutaneous Coronary intervention  Includes:  Percutaneous transluminal coronary angioplasty  Stent placement  Laser angioplasty  Atherectomy o Transmyocardial laser revascularization o Endarterectomy Pathology: The Heart and Blood Vessel o Endocarditis  Emboli o Mitral valve prolapse  Mitral regurgitation o Murmur o Pericarditis  Inflammation of the pericardium o Rheumatic heart disease  Rheumatic fever o Blood vessels:  Aneurysm  Varicose veins 

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 Deep vein thrombosis  Traveler’s thrombosis  Raynaud disease Laboratory Tests o Tests of cardiac cell proteins:  B -type natriuretic protein (BNP)  Cardiac troponin (cTnI, cTnT)  Creatinekinase-MB (CK-MB) o Lipid test profile  Total cholesterol  Triglyceride  Ratio: TC/HDL or LDL/HDL o Lipoprotein analysis:  High density lipoprotein (HDL)  Low density lipoprotein (LDL)  Very low-density lipoprotein (VLDL Clinical procedures: Diagnostic o X-ray  Angiography or arteriography  Computerized tomography angiography o Ultrasound tests  Doppler ultrasound  Echocardiography o Nuclear cardiology  Positron emission tomography scan  Technetium ggm sestamibi scan  Thallium-201 scan o Magnetic resonance imaging (MRI)  Cardiac MRI o Electrocardiography  Normal sinus rhythm  Regularity of the P, QRS, and T waves  Atrial flutter  Rapid atrial rate  Atrial fibrillation  P waves are replaced by irregular and rapid fluctuations  Ventricular tachycardia  Rate may be as high as 250 beats per minutes o Other diagnostic procedures:  Cardiac catheterization  Holtermonitoring  Cardiac stress test...