yN HANDBOOK OF U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE a ea a — a mn DY &: ''pulmonary superior j vena cava atrial septum a - vein pulmonary § ; waive aortic inférior >) valve vena cava _ mitral valve ventricle ventricle ventricular septum a endocardium myocardium epicardium . pericardium ———— apex 4 os RIGHT SIDE OF HEART | LEFT SIDE OF HEART ''A HANDBOOK OF HEART TERM Y) brrders label > US PAS. he 4 DOCUMENTS DEPARTMENT U.S. DEPARTMEN A BINA) HEALTH, EDUCATION, ale hAange4 “af Lu S Public Haalth Servic PALS. peo 4073 National Ins itutes of He thy. CALIFORNIA ay +9 54 ''of 7th ort ve ue ruse HEALTH LIBRARY PREPARED By THE Heart INFORMATION CENTER National Heart Institute e Bethesda, Md. 20014 Public Health Service Publication No. 1073 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C., 20402 -— Price 30 cents ''~ A HANDBOOK OF HEART TERMS was written to give clear definitions in non-technical language. Its purpose is to make reading and writing about heart sub- jects easier, especially for people who communicate with the public on these matters. The Handbook contains a selection of words and phrases commonly used in the heart field. Frequency of use and the: possibility of general unfamiliarity were the only criteria for inclusion. Included are words from medicine, anatomy, physi- ology, instrumentation, pharmacology, and some special terms used by certain related professions dealing with the subject of heart disease. The terms are arranged alpha- betically, and each term is followed by a phonetic spelling to indicate its preferred pronunciation. [Illustrations are included where necessary for clarity. 724 soe mM '' '' ADRENALIN (ad-ren’al-in) One of the secretions of two small glands, called adrenal glands, located just above the kidneys. This secretion, also called epinephrine, and sometimes prepared syn- thetically, constricts the small blood vessels (arterioles), increases the rate of heart beat, and raises blood _pres- sure. It is called a vasoconstrictor or vasopressor substance. AGE-ADJUSTED DEATH RATE Also called age-adjusted mortality rate. Death rates which have been standardized for age for the purpose of making comparisons between different populations or within the same population at various intervals of time. AGE-SPECIFIC DEATH RATE Also called age-specific mortality rate. The ratio of deaths in a specific age group to the population of the same age group during a given period of time, such as a year. It is calculated by dividing the deaths that oc- curred among the specific age group during the year, by the mid-year population in the same group (estimated population in the age group on July 1) of the same year. AMINE (am’ in) An organic compound that may be derived from am- monia by the replacement of one or more of the hydro- gen atoms by hydrocarbon radicals. ''ANEURYSM (an’u-rizm) A spindle-shaped or sac-like bulging of the wall of a vein or artery, due to weakening of the wall by disease or an abnormality present at birth. ANGINA PECTORIS (an’jin-ah pek’to-ris) or (an-ji’nah pek’ to-ris) Literally means chest pain. A condition in which the heart muscle receives an insufficient blood supply, caus- ing pain in the chest, and often in the left arm and shoulder. Commonly results when the arteries supply- ing the heart muscle (coronaries) are narrowed by atherosclerosis. See Coronary Atherosclerosis. ANGIOCARDIOGRAPHY (an’ je-o-kar-de-og’ rah-fe) X-ray examination of the heart and great blood vessels that follows the course of an opaque fluid which has been injected into the blood stream. ANOREXIA (an-o-rek’se-ah) Lack or loss of appetite for food. ANOXIA (an-ok’ se-ah) Literally, no oxygen. This condition most frequently occurs when the blood supply to a part of the body is completely cut off. This results in the death of the affected tissue. For example, a specific area of the heart muscle may die when the blood supply (and hence the oxygen supply) has been blocked, as by a clot in the artery supplying that area. ANTICOAGULANT (an’te-ko-ag’u-lant) A drug which delays clotting of the blood. When given in cases of a blood vessel plugged up by a clot, it tends to prevent new clots from forming, or the existing clots from enlarging, but does not dissolve an existing clot. Examples are heparin and coumarin derivatives. ''“ANTIHYPERTENSIVE AGENTS (an’te-hi-per-ten’ siv) Drugs which are used to lower blood pressure such as rauwolfia, reserpine, veratrum, hydralazine, hexametho- nium chloride, and many others. ANXIETY (ang-zi’e-te) A feeling of apprehension, the source of which is un- recognized. AORTA (a-or’tah) The main trunk artery which receives blood from the lower left chamber of the heart. It originates from the base of the heart, arches up over the heart like a cane handle, and passes down through the chest and abdomen in front of the spine. It gives off many lesser arteries which conduct blood to all parts of the body except the lungs. aortic’aréh Vb \ AORTIC ARCH (a-or'’ tik) The part of the aorta or large artery leaving the heart, which curves up like the handle of a cane over the top of the heart. AORTIC INSUFFICIENCY (a-or’ tik) An improper closing of the valve between the aorta and the lower left chamber of the heart admitting a back flow of blood. 3 ''AORTIC STENOSIS (a-or’ tik ste-no’ sis) A narrowing of the valve opening between the lower left — chamber of the heart and the large artery called the aorta. The narrowing may occur at the valve itself or slightly above or below the valve. Aortic stenosis may be the result of scar tissue forming after a rheumatic fever infection, or may have other causes. AORTIC VALVE (a-or’ tik) Valve at the junction of the aorta, or large artery, and the lower left chamber of the heart. Formed by three cup- shaped membranes _ called semilunar valves, it allows the blood to flow from the heart into the artery and prevents a back flow. AORTOGRAPHY (a-or-tog’ rah-fe) X-ray examination of the aorta (main artery conduct- ing blood from the lower left chamber of the heart to the body) and its main branches. This is made possible by the injection of a dye which is opaque to X-rays. valve APEX (a’peks) The blunt rounded end of the heart, directed downward, forward, and to the left. apex APOPLEXY (ap’o-plek-se) Frequently called apoplectic stroke or simply a stroke. A sudden interruption of the blood supply to a part of the brain -caused by the obstruction or rupture of an artery. Initially may be manifested by a loss of con- sciousness, sensation, or voluntary motion, and may leave a part of the body (frequently one side) temporarily or permanently paralyzed. ''ARRHYTHMIA (ah-rith’me-ah) An abnormal rhythm of the heart beat. ARTERIAL BLOOD (ar-te’re’ al) Oxygenated blood. The blood is oxygenated in the lungs, passes from the lungs to the left side of the heart via the pulmonary veins. It is then pumped by the left side of the heart into the arteries which carry it to all parts of the body. See Venous Blood. ARTERIOLES (ar-te’re-ols) The smallest arterial vessels (about 0.2 mm. or 1/125 inch in diameter) resulting from repeated branching of the arteries. They-conduct the blood from the arteries to the capillaries. ARTERIOSCLEROSIS (ar-te’re-o-skle-ro’sis) Commonly called. hardening of the arteries. This is a generic term which includes a variety of conditions which cause the artery walls to become thick and hard and lose elasticity. See Atherosclerosis. ARTERY (ar’ter-e) Blood. vessels which carry blood away from the heart to the various parts of the body. They usually carry oxy- genated blood except for the pulmonary artery which carries unoxygenated blood from the heart to the lungs for oxygenation. See Vein. ASCHOFF BODIES (ash of) Spindle-shaped nodules, occurring most frequently in the tissue of the heart, often formed during an attack of rheu- matic fever. Named after Ludwig Aschoff (1866-1942) a German pathologist who described them. 714-731 O-64—2 5 ''— ATHEROMA (ath-er-o’ mah) A deposit of fatty (and other) substances in the inner lining of the artery wall, characteristic of atherosclerosis. Plural form of the word is atheromata (ath-er-o-mah’‘ta). See Atherosclerosis. ATHEROSCLEROSIS (ath’er-o-skle-ro’ sis) A kind of arteriosclerosis in which the inner layer of the artery wall is made thick and irregular by deposits of a fatty substance. These deposits (called atheromata) pro- ject above the surface of the inner layer of the artery, and thus decrease the diameter of the internal channel of the vessel. See Arteriosclerosis. atherosclerosis ATRIAL SEPTUM (a’tre-al sep’ tum) Sometimes called inter-atrial septum or inter-auricular septum. Muscular wall dividing left and right upper chambers of the heart which are called atria. See Septum. ATRIO-—VENTRICULAR BUNDLE (a’tre-o-ven-trik’ u-lar) Also called Bundle of His, auriculo-ventricular bundle, or A-V bundle. A bundle of specialized muscle fibers running from a small mass of muscular fibers (atrio- ventricular node) between the upper chambers of the heart, down to the lower chambers. It is the only known direct muscular connection between the upper and lower heart chambers, and serves to conduct im- pulses for the rhythmic heart beat from the atrio- ventricular node to the heart muscle. ''ATRIO-VENTRICULAR NODE (a’ tre-o-ven-trik’ u-lar) A small mass of special muscular fibers at the base of the wall between the two upper chambers of the heart. It forms the beginning of the Bundle of His which is the only known direct muscular connection between the upper and the lower chambers of the heart. The elec- trical impulses controlling the rhythm of the heart are generated by the pacemaker, conducted through the muscle fibers of the right upper chamber of the heart to the atrio-ventricular node, and then conducted to the lower chambers of the heart by the Bundle of His. See Bundle of His. ATRIO-—VENTRICULAR VALVES (a’tre-o-ven-trik’u-lar) The two valves, one in each side of the heart, between the upper and lower chamber. The one in the right side of the heart is called the tricuspid valve, and the one in the left side is called the mitral valve. ATRIUM (a’tre-um) One of the two upper cham- fight \ atrium bers of the heart. line called ee a auricle, although this is now generally used to describe only the very tip of the atrium. Right atrium receives un-oxy- genated blood from body. Left atrium receives oxygen- ated blood from lungs. Ca- pacity in adult about 57 cc. AUENBRUGGER, LEOPOLD JOSEPH (1722-1809) Austrian physician who invented the technique of tap- ping the surface of the body to determine the condition of organs beneath. The technique is called percussion. AURICLE (aw’re-kl) The upper chamber in each side of the heart. “Atrium” is another term commonly used for this chamber. ''AURICULAR SEPTUM (aw-rik’u-lar sep’tum) Sometimes called inter-auricular septum or, more prop- erly, inter-atrial septum. Muscular wall dividing left and right upper chambers of the heart which are called atria. See Septum. AURICULO-VENTRIULAR BUNDLE (aw-rik’u-lo-ven-trik’ u-lar) See Bundle of His. AUSCULTATION (aws-kul-fa’shun) The act of listening to sounds within the body, usually with a stethoscope. AUTONOMIC NERVOUS SYSTEM (aw-to-nom’ ik) Sometimes called involuntary nervous system or vegeta- tive nervous system, it controls tissues not under volun- tary control, e.g., glands, heart, and smooth muscles. A-V BUNDLE See Bundle of His. BACTERIAL ENDOCARDITIS (bak-te’re-al en’do-kar-di'’ tis) An inflammation of the inner layer of the heart caused by bacteria. The lining of the heart valves is most fre- quently affected. It is most commonly a complication of an infectious disease, operation, or injury. ''BALLISTOCARDIOGRAM (bal-is’to-kar’de-o-gram) A tracing of the movements of the body caused by the beating of the heart. The instrument which records these movements is called a ballistocardiograph. BALLISTOCARDIOGRAPH (bal-is’ to-kar’de-o-graf) An apparatus for recording the movements of the body caused by the beating of the heart. BARBITURATE (bar-bit’u-rat) A. class of drugs which produce a calming effect. A sedative. BENZOTHIADIAZINE (ben-zo-thi-ah-di’ ah-zin) A drug used to increase the output of urine by the kidney. A diuretic. . BICUSPID VALVE (bi-kus’ pid) Usually called mitral valve. A valve of two cusps or triangular segments, located between the upper and lower chamber in the left side of the heart. BLOOD PRESSURE The pressure of the blood in the arteries. 1. Systolic blood pressure. Blood pressure when the heart muscle is contracted (systole). 2. Diastolic blood pressure. Blood pressure when the heart muscle is relaxed between beats (diastole). Blood pressure is generally expressed by two numbers, as 120/80, the first representing the systolic, and the second, the diastolic pressure. ''BLUE BABIES Babies having a blueness of skin (cyanosis) caused by insufficient oxygen in the arterial blood. This often in- dicates a heart defect, but may have other causes such as premature birth or impaired respiration. BRADYCARDIA (brad-e-kar’de-ah) Abnormally slow heart rate. Generally, anything below 60 beats per minute is considered bradycardia. BRIGHT, RICHARD (1789-1858) English physician who demonstrated the association of heart disease with kidney disease. BROMIDE (bro’ mid) Any one of several drugs which produce a calming effect. A sedative. BUNDLE OF HIS (hiss) Also called auriculo-ventricular bundle, atrio-ventricular bundle, or A-V bundle. A bundle of specialized muscle fibers running from a small mass of muscular fibers (atrio-ventricular node) between the upper chambers of the heart, down to the lower chambers. It is the only known direct muscular connection between the upper and lower heart chambers, and serves to conduct im- pulses for the rhythmic heart beat from the atrio- ventricular node to the heart muscle. Named after Wilhelm His, German anatomist. 10 ''ac CAESALPINUS, ANDREAS (1519?-1603) - First to use the term “circulation” in connection with the movement of the blood. However, he still believed in many of the classical theories taught by Galen. CALORIE (kal’o-re) Sometimes called large or kilo-calorie. Unit used to ex- press food energy. The amount of heat required to raise the temperature of 1 kilogram of water 1 degree Centi- grade. A high caloric diet has a prescribed caloric value above the total daily energy requirement. A low caloric diet has a prescribed caloric value below the total energy requirement. CAPILLARIES (kap’i-lar-ez) Extremely narrow tubes form- ing a network between the arterioles and the veins. The capillaries walls are composed of a single layer of cells through which oxygen and nutritive materials pass out to the tissues, and car- bon dioxide and waste prod- ucts are admitted from the tis- sues into the blood stream. ae CARDIAC (kar’de-ak) Pertaining to the heart. Sometimes refers to a person who has heart disease. 11 ''CARDIAC CYCLE (kar’de-ak) One total heart beat, i.e., one complete contraction and relaxation of the heart. In man, this normally occupies about 0.85 second. CARDIAC OUTPUT (kar’de-ak) The amount of blood pumped by the heart per minute. CARDIOVASCULAR (kar’de-o vas’ku-lar) Pertaining to the heart and blood vessels. CARDIOVASCULAR-RENAL DISEASE (kar’de-o-vas’ku-lar re’nal) Disease involving the heart, blood vessels, and kidneys. CARDITIS (kar-di’tis) Inflammation of the heart. CAROTID ARTERIES (kah-rot’id) The left and right common carotid arteries are the prin- cipal arteries supplying the head and neck. Each has two main branches, external carotid artery and internal carotid artery. CAROTID BODY (kah-rot’id) A small oval mass of cells and nerve endings about 5 mm. or % inch long located in the carotid sinus—that is, at the branching point in the arteries supplying blood to the head and neck. The cells respond to chemical changes in the blood by causing changes in the rate of breathing, and certain other body changes. When the oxygen content of the blood is reduced, the carotid body Causes an increase in respiration rate. 12 ''CAROTID SINUS (kah-rot’id si’nus) A slight dilation at the point where the internal carotid artery branches from the common carotid artery. The carotid arteries are those arteries which supply blood to the head and neck. The carotid sinus contains special nerve end organs which respond to a change in blood pressure by causing a change in the rate of heart beat. External pressure on the carotid sinus by stimulating some of the nerves in the sinus can also cause a drop in blood pressure and faintness. CATHETER (kath’e-ter) ne carneter A cardiac catheter is a diag- nostic device for taking samples of blood, or pressure readings within the heart chambers which might reveal defects in the heart. It is a thin tube of woven plastic or other mate- rial to which blood will not adhere, which is inserted in a vein or artery, usually in the arm, and threaded into the heart. The catheter is guided by the physician who watches its progress by means of X-rays falling on a fluo- rescent screen. Catheters are also used to enter other tubular organs. CATHETERIZATION (kath’e-ter-i-za’shun) In cardiology, the process of examining the heart by means of introducing a thin tube (catheter) into a vein or artery and passing it into the heart. CEREBRAL VASCULAR ACCIDENT (ser’e-bral vas’ku-lar) Sometimes called cerebrovascular accident, apoplectic stroke, or simply stroke. An impeded blood supply to 'some part of the brain, generally caused by one of the following four conditions: 13 714-731 O-64—3 ''1. a blood clot forming in the vessel (cerebral thrombosis) 2. a rupture of the blood vessel wall (cerebral hemor- rhage) 3. a piece of clot or other material from another part of the vascular system which flows to the brain and obstructs a cerebral vessel (cerebral embolism) 4. pressure on a blood vessel as by a tumor. CEREBROVASCULAR (ser’e-bro-vas’ku-lar) Pertaining to the blood vessels in the brain. CHAGAS HEART DISEASE (chah’gahs) A form of heart disease resulting from an infection by a microscopic parasite found in South America. CHEMOTHERAPY (ke-mo-ther’ah-pe) The treatment of disease by administering chemicals. Frequently used in the phrase “chemotherapy of hyper- tension”, i.e., the treatment of high blood pressure by the use of drugs. CHLORAL HYDRATE (klo’ral hi’drat) A drug, which has a calming action, used to induce sleep. A sedative. 14 ''CHLOROTHIAZIDE (klo-ro-thi’ah-zid) A chemical compound which increases the output of urine. One of the diuretics sometimes used in the treatment of edema, or water-logged tissues. CHOLESTEROL (ko-les’ter-ol) A fat-like substance found in animal tissue. In blood tests the normal level for Americans is assumed to be be- tween 180 and 230 milligrams per 100 cc. A higher level is often associated with high risk of coronary atherosclerosis. CHORDAE TENDINEAE (kor’di ten-din’e-i) Fibrous chords which serve as guy ropes to hold the valves between the upper and lower chambers of the heart secure when forced closed by pressure of blood in the lower chambers. They stretch from the cusps of the valves to muscles called papillary muscles in the walls of the lower heart chambers. CHOREA (ko-re’ah) Involuntary, irregular twitching of the muscles sometimes associated with rheumatic fever. Also called St. Vitus Dance, or Sydenham’s Chorea. CIRCULATORY (ser’ku-lah-to-re) Pertaining to the heart, blood vessels, and the circulation of the blood. CLAUDICATION (klaw-de-ka’shun) Pain and lameness or limping caused by defective circu- lation of the blood in the vessels of the limbs. 15 ''CLUBBED FINGERS (klubd) Fingers with a short broad tip and overhanging nail, somewhat resembling a drumstick. This condition is sometimes seen in children born with certain kinds of heart defects. COAGULATION (ko-ag-u-la’shun) Process of changing from a liquid to a thickened or solid state. The formation of a clot. COARCTATION OF THE AORTA (ko-ark-ta’shun of the a-or’ta) Literally a pressing together, coarctation or a narrowing of the aorta "A of the which is the main trunk artery which conducts blood from the heart to the body. One of several types of congenital heart defects. aorta COLLATERAL CIRCULATION (ko-lat’er-al ser-ku-la’shun) Circulation of the blood through nearby smaller vessels when a main vessel has been blocked up. COMMISSUROTOMY (kom’e-sur-ot’o-me) An operation to widen the opening in a heart valve which has become narrowed by scar tissue. The indi- vidual flaps of the valve are cut or spread apart along ‘the natural line of their closure. This operation often performed in cases of rheumatic heart disease. See Mitral Valvulotomy. 16 ''COMPENSATION (kom-pen-sa’shun) A change in the circulatory system made to compensate for some abnormality. An adjustment of size of heart or rate of heart beat made to counterbalance a defect in structure or function. Often used specifically to describe the maintenance of adequate circulation in spite of the presence of heart disease. CONGENITAL ANOMALY (kon-jen’i-tal ah-nom’ah-le) An abnormality present at birth. CONGESTIVE HEART FAILURE (kon-jes’tiv) When the heart is unable adequately to pump out all the blood that. returns to it, there is a backing up of blood in the veins leading to the heart. A congestion or accumulation of fluid in various parts of the body (lungs, legs, abdomen, etc.) may result from the heart’s failure to maintain a satisfactory circulation. See Myocardial Insufficiency. CONSTRICTION (kon-strik’shun) Narrowing, as in the phrase “vaso-constriction”, which is a narrowing of the internal diameter of the blood vessels, caused by a contraction of the muscular coat of the vessels. CONSTRICTIVE PERICARDITIS (kon-strik’tiv per’e-kar-di’tis) A shrinking and thickening of the outer sac of the heart which prevents the heart muscle from expanding and contracting normally. CONTRACTILE PROTEINS (kon-trak’til pro’te-ins) The protein substance within the heart muscle fibers re- sponsible for heart contraction by shortening the muscle fibers. 17 ''CORONARY ARTERIES (kor’o-na-re) Two arteries, arising from the aorta, arching down over the top of the heart, and conduct- ing blood to the heart muscle. CORONARY ATHEROSCLEROSIS (kor’o-na-re ath’er-o-skle-ro’ sis) Commonly called coronary heart disease. An irregular thickening of the inner layer of the walls of the arteries which conduct blood to the heart muscle. The internal channel of these arteries (the coronaries) becomes nar- rowed and the blood supply to the heart muscle is reduced. See Atherosclerosis. CORONARY OCCLUSION (kor’o-na-re ok-klu’zhun) An obstruction (generally a blood clot) in a branch of one of the coronary arteries which hinders the flow of blood to some part of the heart muscle. This part of the heart muscle then dies because of lack of blood supply. Sometimes called a coronary heart attack, or simply a heart attack. coronary occlusion CORONARY THROMBOSIS (kor’o-na-re throm-bo’sis) Formation of a clot in a branch of one of the arteries which conduct blood to the heart muscle (coronary arter- ies). A form of coronary occlusion. See Coronary Occlusion. 18 ''COR PULMONALE (kor’ pul-mo-nal’e) Heart disease resulting from disease of the lungs or the blood vessels in the lungs. This is due to resistance to the passage of blood through the lungs. CORVISART, JEAN NICOLAS (1755-1821) One of earliest of the modern cardiologists, and the first man to call himself a “heart specialist”. Favorite physi-. cian to Napoleon. COUMARIN (koo’mah-rin) A class of chemical substances which delay clotting of the blood. An anti-coagulant. CRUDE DEATH RATE (krood) Also called crude mortality rate. The ratio of total deaths to total population during a given period of time, such as a year. It is calculated by dividing the total number of deaths during the year by the mid-year popu- lation (estimated population on July 1) of the same year. CYANOSIS (si-ah-no’sis) Blueness of skin caused by insufficient oxygen in the blood. Oxygen is carried in the blood by hemoglobin, which is bright red when saturated with oxygen. When hemoglobin is not carrying oxygen, it is purple and is called reduced hemoglobin. The blueness of the skin oc- curs when the amount of reduced hemoglobin exceeds 5 grams per 100 cc. of blood. CYTOLOGIC (si-to-loj’ik) Pertaining to cells, their anatomy, physiology, pathology, and chemistry. 19 '' DECOMPENSATION (de-kom-pen-sa’shun) Inability of the heart to maintain adequate circulation, usually resulting in a waterlogging of tissues. A person whose heart is failing to maintain normal circulation is said to be “decompensated”. DEFIBRILLATOR (de-fi’bre-la-tor) Any agent or measure, such as an electric shock, which stops an incoordinate contraction of the heart muscle and restores a normal heart beat. DEPRESSANT (de-pres’ant) Any drug which decreases functional activity. DESCARTES, RENE (1596-1650) Author of the first physiology textbook which accepted the theory of the circulation of the blood as described by William Harvey. DEXIOCARDIA (dek’se-o-kar’de-ah) Same as dextrocardia. DEXTROCARDIA (deks-tro-kar’de-ah) Two different types of congenital phenomena are often described as dextrocardia. The first is a condition in 20 ''which the heart is slightly rotated and lies almost en- tirely in the right (instead of the left) side of the chest. The second is a condition in which there is a complete transposition, the left chambers of the heart being on the right side, and the right chambers on the left side, so that the heart presents a mirror image of the normal heart. DIASTOLE (di-as’to-le) In each heart beat, the period of the relaxation of the heart. Auricular diastole is the period of relaxation of the atria, or upper heart chambers. Ventricular diastole is the period of relaxation of the ventricles, or lower heart chambers. DIET (di’et) Daily allowance or intake of food and drink. DIETETICS (di-e-tet’iks) The science and art dealing with the application of principles of nutrition to the feeding of individuals or groups under different economic or health conditions. DIETITIAN (di-e-tish’an) One skilled in the scientific use of diet in health and disease. DIGITALIS (dig-e-tal’is, dig-e-ta’lis) A drug prepared from leaves of foxglove plant which strengthens the contraction of the heart muscle, slows the rate of contraction of the heart, and by improving the efficiency of the heart, may promote the elimination of fluid from body tissues. 714-731 O-64—4 21 ''DILATION (di-la’shun) A stretching or enlargement of the heart or blood vessels beyond the norm. : DIURESIS (di-u-re’sis) Increased excretion of urine. DIURETIC (di-u-ret’ik) A medicine which promotes the excretion of urine. Sev- eral types of drugs may be used, such as mercurials, chlorothiazide, xanthine, and benzothiadiazine derivatives. DUCTUS ARTERIOSUS (duk’tus ar-te’re-o’sis) A small duct in the heart of the fetus between the artery leaving the left side of the heart (aorta) and the artery leaving the right side of the heart (pulmonary artery). Normally this duct closes soon after birth. If it does not close, the condition is known as patent or open ductus arteriosus. See Patent Ductus Arteriosus. DYSPNEA (disp-ne’ah) Difficult or labored breathing. eee 7 ECG See Electrocardiogram. 22 ''ECTOMORPH (ek’-to-morf) Wiry body type. EDEMA (e-de’mah) Swelling due to abnormally large amounts of fluid in the tissues of the body. EFFORT SYNDROME (sin’drom) A group of symptoms (quick fatigue, rapid heart beat, sighing breaths, dizziness) that do not result from disease of organs or tissues and that are out of proportion to the amount of exertion required. EKG See Electrocardiogram. ELECTRIC CARDIAC PACEMAKER (kar’de-ak pas’mak-er) An electric device that can control the beating of the heart by a rhythmic discharge of electrical impulses. ELECTROCARDIOGRAM (e-lek’tro-kar’de-o-gram) Often referred to as EKG or ECG. A graphic record of the electric currents produced by the heart. 23 ''ELECTROCARDIOGRAPH (e-lek’tro-kar’ de-o-graf) An instrument which records electric currents produced by the heart. ELECTROLYTE (e-lek’tro-lit) Any substance which, in solution, is capable of conduct- ing electricity by means of its atoms or groups of atoms, and in the process is broken down into positively and negatively charged particles. Examples, sodium or potassium. EMBOLISM (em’bo-lizm) The blocking of a blood vessel by a clot or other sub- stance carried in the blood stream. EMBOLUS (em’bo-lus) A blood clot (or other substance such as air, fat, tumor) inside a blood vessel which is carried in the blood stream to a smaller vessel where it becomes an obstruction to - circulation. See Thrombus. ENDARTERIUM (end-ar-te’re-um) Also called intima. The innermost layer of an artery. ENDOCARDITIS (en’do-kar-di’ tis) Inflammation of the inner layer of the heart (endo- cardium) usually associated with acute rheumatic fever or some infectious agents. 24 ''ENDOCARDIUM (en-do-kar’de-um) A thin smooth membrane forming the inner surface of the heart. ENDOMORPH (en’do-morf) Short and thickset body type. ENDOTHELIUM (en-do-the’le-um) The thin lining of the blood vessels. ENZYME (en’zim) A complex organic substance which is capable of speed- ing up specific biochemical processes in the body. En- zymes are universally present in living organisms. EPICARDIUM (ep-e-kar’de-um) The outer layer of the heart wall. Also called the visceral pericardium. epicardium EPIDEMIOLOGY (ep’e-de-me-ol’o-je) The science dealing with the factors which determine the frequency and distribution of a disease in a human community. EPINEPHRINE (ep-e-nef’rin) One of the secretions of two small glands, called adrenal glands, located just above the kidneys. This secretion, 25 ''also called adrenalin, and sometimes prepared syntheti- cally, constricts the small blood vessels (arterioles), in- creases the rate of heart beat, and raises blood pressure. It is called a vasoconstrictor or vasopressor substance. ERYTHROCYTE (e-rith’ro-sit) Red blood cell. ESSENTIAL HYPERTENSION (hi-per-ten’shun) Sometime called primary hypertension, and commonly known as high blood pressure. An elevated blood pres- sure not caused by kidney or other evident disease. ETIOLOGY (e-te-ol’o-je) The sum of knowledge about the causes of a disease. EXTRACORPOREAL CIRCULATION (eks’trah-kor-po’re-al) The circulation of the blood outside the body as by a mechanical pump-oxygenator. This is often done while surgery is being performed inside the heart. EXTRASY STOLE (eks-trah-sis’ to-le) A contraction of the heart which occurs prematurely and interrupts the normal rhythm. EYEGROUND (i’ground) The inside of the back part of the eye seen by looking through the pupil. Examining the eyeground is one means of assessing changes in the blood vessels. Also called the fundus of the eye. 26 ''or 7 FABRICIUS AB AQUAPENDENTE, HIERONYMUS (1560-1634) Italian anatomist, a teacher of William Harvey at Padua. He studied the valves of the veins and Harvey is reported to have credited the work of Fabricius with leading to his own concept of the circulation of the blood. FALLOT, ETIENNE LOUIS ARTHUR (1850-1911) (fal-d) French physician who gave an important description of a congenital heart defect known as the tetralogy of Fallot. See Tetralogy of Fallot. FEMORAL ARTERY (fem/’or-al ar’ter-e) Main blood vessel supplying blood to the leg. FIBRILLATION (fi-bre-la’shun) Uncoordinated contractions of the heart muscle occurring when the individual muscle fibers take up independent irregular contractions. FIBRIN (fi’brin) An elastic protein which forms the essential portion of a blood clot. FIBRINOGEN (fi-brin’o-jen) A soluble protein in the blood which, by the action of certain enzymes, is converted into the insoluble protein of a blood clot. 27 ''FIBRINOLYSIN (fi-bre-nol'is-in) An enzyme which can cause coagulated blood to return to a liquid state. FIBRINOLYTIC (fi’brin-o-lit’ik) Having the ability to dissolve a blood clot. FLUORESCENT ANTIBODY TEST (flu-o-res’ent an’te-bod-e) A rapid and sensitive test for certain disease organisms and substances. _Its value in the field of heart disease is that it speeds the recognition of harmful streptococci in a throat smear, so that immediate treatment might avert an attack of rheumatic fever. The test consists of “tagging” with a fluorescent dye the antibodies, i.e., sub- stances in blood serum that have been built up against certain bacteria. This dyed antibody is then mixed with a smear taken from the throat of the patient. If strep- tococci are present in the smear, the glowing antibodies will attach to them, and they can be clearly seen in the microscope. FLUOROSCOPE (floo-o’ro-skop) An instrument for observing structures deep inside the body. X-rays are passed through the body onto a fluo- rescent screen where the shadow of deep lying organs can be seen. FLUOROSCOPY (floo-or-os’ko-pe) The examination of a structure deep in the body by means of observing the fluorescence of a screen caused by X-rays transmitted through the body. 28 ''~ FORAMEN OVALE (fo-ra’men o-va‘le) An oval hole between the left and right upper chambers of the heart which normally closes shortly after birth. Its failure to close is one of the congenital defects of the heart, called a patent foramen ovale. FUNDUS OF THE EYE (fun’dus) The inside of the back part of the eye seen by look- ing through the pupil. Examining the fundus of the eye is used as a means of assessing changes in the blood vessels. Also called the eyeground. ace GALEN (CLAUDIUS GALENUS) (c. 130-200 A.D.) Renowned Greek physician whose theory that life and health depended upon the balance of four “humors” in the body, dominated medical practice for 1500 years. His concept of the ebb and flow of the blood which transported the humors to various parts of the body, was not refuted until William Harvey’s discovery of the cir- - culation of the blood in 1628. GALLOP RHYTHM An extra, clearly heard heart sound which, when the heart rate is fast, resembles a horse’s gallop. It may or may not be significant. GANGLION (gang’gle-on) A mass of nerve cells, which serves as a center of nervous influence. 714-731 O-64—5 29 ''GANGLIONIC BLOCKING AGENTS (gang-gle-on’ik) A drug that blocks the transmission of a nerve impulse at the nerve centers (ganglia). Some of these drugs, such as hexamethonium and mecamylamine hydrochloride, may be used in the treatment of high blood pressure. GENETICS (je-net’iks) - The study of heredity. or a HARVEY, WILLIAM (1578-1657) English physician who discovered the circulation of the blood and described his theory in 1628 in his classic work De Motu Cordis. HEART BLOCK Interference with the conduction of the electrical impulses of the heart which can be either partial or complete. This can result in dissociation of the rhythms of the upper and lower heart chambers. HEART-LUNG MACHINE A machine through which the blood stream is diverted for pumping and oxygenation while the heart is opened for surgery. See Extracorporeal Circulation. 30 ''HEMIPLEGIA (hem-e-ple’je-ah) Paralysis of one side of the body caused by damage to the opposite side of the brain. The paralyzed arm and leg are opposite to the side of the brain damage because the nerves cross in the brain, and one side of the brain con- trols the opposite side of the body. Such paralysis is sometimes caused by a blood clot or hemorrhage in a blood vessel in the brain. See Stroke. HEMODYNAMICS (he’mo-di-nam’iks) The study of the flow of blood and the forces involved. HEMOGLOBIN (he-mo-glo’bin) The oxygen-carrying red pigment of the red blood cor- puscles. When it has absorbed oxygen in the lungs, it is bright red and called oxy-hemoglobin. After it has given up its oxygen load in the tissues, it is purple in color, and is called reduced hemoglobin. HEMORRHAGE (hem/’or-ij) Loss of blood from a blood vessel. In external hemor- rhage blood escapes from the body. In internal hemor- rhage blood passes into tissues surrounding the ruptured blood vessel. HEPARIN (hep’ah-rin) A chemical substance which tends to prevent blood from clotting. Sometimes used in cases of an existing clot in an artery or vein to prevent enlargement of the clot or the formation of new clots. An anticoagulant. HEXAMETHONIUM CHLORIDE (hek’sah-meth-own’e-um klo’ride) A drug which lowers blood pressure and increases blood flow by interfering with the transmission of nerve impulses 31 ''which constrict the blood vessels. One of the ganglionic blocking agents, it is one of the drugs used in the treatment — of high blood pressure. / HIS, WILHELM (1831-1904) German anatomist who discovered bundle of muscle fibers running from the upper to lower chambers of heart. These fibers are known as “Bundle of His”. HISTOLOGY (his-tol’o-je) The study of the anatomy of the cells and minute struc- tures of the tissues and organs. HYDRALAZINE HYDROCHLORIDE (hi-drahl’a-zin hi-dro-klo’ride) A drug which lowers blood pressure. One of the anti- | hypertensive agents. HYPERCHOLESTEREMIA (hi’per-ko-les’ter-e’me-ah) An excess of a fatty substance called cholesterol in the# blood. Sometimes called hypercholesterolemia or hyper-— cholesterinemia. See Cholesterol. HYPERLIPEMIA (hi-per-li-pe’me-ah) An excess of fat or lipids in the blood. HYPERTENSION (hi-per-ten’shun) Commonly called high blood pressure. An unstable or persistent elevation of blood pressure above the normal range, which may eventually lead to increased heart size and kidney damage. See Primary Hypertension and Sec- ondary Hypertensvon. 3 32 '' HYPERTHYROIDISM (hi-per-thi’roid-izm) A condition in which the thyroid gland is overly active. This may eventually result in a speeded up rate of heart beat. HYPERTROPHY (hi-per’tro-fe) The enlargement of a tissue or organ due to increase in the size of its constituent cells. This may result from a demand for increased work. HYPOTENSION (hi-po-ten’shun) Commonly called low blood pressure. Blood pressure below the normal range. Most commonly used to de- scribe an acute fall in blood pressure, as occurs in shock. HYPOTHALAMUS (hi-po-thal’ah-mus) A part of the brain which exerts control over activity of the abdominal organs, water balance, temperature, etc. Damage to the hypothalamus may cause abnormal gain in weight, among other things. HYPOTHERMIA (hi-po-ther’me-ah) Also called hypothermy. The lowering of the body tem- perature (usually to 86°-88° F.),in order to slow the metabolic processes during heart surgery. In this cooled state, body tissues require less oxygen. HYPOTHYROIDISM (hi-po-thi’roid-izm) A condition in which the thyroid gland is underactive, resulting in the slowing down of many of the body proc- esses including the heart rate. 33 ''HYPOXIA (hi-pok’se-ah) Less than normal content of oxygen in the organs and tissues of the body. At very high altitudes a healthy person suffers from hypoxia because of insufficient oxygen in the air that is breathed. IATROGENIC HEART DISEASE (i’at-ro -jen’ik) Literally means “caused by the doctor”. A patient’s be- lief that he has heart disease implied from the actions, manner, or discussions of the physician or some member of the medical team. ILIAC ARTERY (il’e-ak ar’ter-e) A large artery which conducts blood to the pelvis and the legs. INCIDENCE (in’si-dens) ‘The number of new cases of a disease developing in a - given population during a specified period of time, such aS a year. INCOMPETENT VALVE Any valve which does not close tight and leaks blood back in the wrong direction. Also called valvular insufficiency. 34 ''INFARCT (in’farkt) An area of a tissue which is damaged or dies as a result of not receiving a sufficient blood supply. Frequently used in the phrase “myocardial in- farct” referring to an area of the heart muscle damaged or killed by an insufficient flow of blood through the coronary arteries which normally supply it. infarct INNOMINATE ARTERY (in-om’i-nat) One of the largest branches of the aorta. It arises from the arch of the aorta and divides to form the right com- mon carotid artery and the right subclavian artery. INSUFFICIENCY (in-suh-fish’en-se) Incompetency. In the term “valvular insufficiency,” an improper closing of the valves which admits a back flow of blood in the wrong direction. In the term “myo- cardial insufficiency,” inability of the heart muscle to do a normal pumping job. INTER-ATRIAL SEPTUM (in-ter-a’tre-al sep’tum) Sometimes called auricular septum or interauricular sep- tum or atrial septum. Muscular wall dividing left and right upper chambers of the heart which are called atria. INTER-VENTRICULAR SEPTUM (in-ter-ven-trik’u-lar sep’ tum) Sometimes called ventricular septum. Muscular wall, thinner at the top, dividing the left and right lower chambers of the heart which are called ventricles. 35 ''INTIMA (in’te-mah) The innermost layer of a blood vessel. IN VITRO (in vee’tro) Literally means “‘in glass”, hence in a laboratory vessel. Describes a phenomenon studied outside a living body under laboratory conditions. See In Vivo. IN VIVO (in vee’vo) In a living organism. Describes a phenomenon studied in a living body. See In Vitro. ISCHEMIA (is-ke’me-ah) A local, usually temporary, deficiency of blood in some part of the body, often caused by a constriction or an obstruction in the blood vessel supplying that part. ISOTOPE (i’so-tdp) A term applied to one of two elements, chemically iden- tical, but differing in some other characteristic, such as radioactivity. Radioactive isotopes are often used in medicine to trace the fate of substances in the body. JUGULAR VEINS (jug’v-lar) Veins which return blood from the head and neck to the heart. 36 '' LAENNEC, RENE THEOPHILE HYACINTHE (1781-1826) French physician who invented the stethoscope. LEEUWENHOEK, ANTONJ VAN (1632-1723) Dutch microscopist who, among other scientific contri- butions, discovered the interwoven structure of the mus- cle fibers of the heart. LEVARTERENOL (lev-ar-te-ren’ol) _ One of the normal secretions of the adrenal glands, and also a drug. It raises blood pressure and is used to treat acute low blood pressure and shock. LINOLEIC ACID (lin-o-lay’ik) An important component of many of the unsaturated fats. It is found widely in oils from plants. A diet with a high linoleic acid content tends to lower the amount of cholesterol in the blood. LIPID (lip’id) Fat. LIPOPROTEIN (lip-o-pro’te-in) A complex of fat and protein molecules. 37 ''LUMEN (lu’men) ‘The passageway inside a tubular organ. Vascular lumen is the passageway inside a blood vessel. oom Vs | MALIGNANT HYPERTENSION (mah-lig’nant hi-per-ten’shun) Severe high blood pressure that runs a rapid course and causes damage to the blood vessel walls in the kidney, eye, etc. MALPIGHI, MARCELLO (1628-1694) Italian anatomist who, among other discoveries, demon- strated the existence of capillary connections between the arteries and veins in the lungs. MECAMYLAMINE HYDROCHLORIDE (mek-a-mil'a-min hi-dro-klor’id) A drug which blocks the transmission of nerve impulses at the nerve centers. One of the ganglionic blocking agents, it may be used in the treatment of high blood pressure. MERCURIAL DIURETIC (mer-ku’re-al di-u-ret’ik) Various organic compounds of mercury commonly used to promote the elimination of water and sodium from the body through increased excretion of urine. Some- times used in congestive heart failure when tissues are water-logged. Mercury in several different organic forms is used as a diuretic. 38 ''MESOMORPH (mes’o-morf) Muscular body type. METABOLISM (me-tab’o-lizm) A general term to designate all chemical changes which occur to substances within the body. MITRAL INSUFFICIENCY (mi’tral) An improper closing of the mitral valve between the upper and lower chamber in the left side of the heart which admits a back flow of blood in the wrong direc- tion. Sometimes the result of scar tissue forming after a rheumatic fever infection. MITRAL STENOSIS (mitral ste-no’sis) A narrowing of the valve (called bicuspid or mitral valve) opening between the upper and the lower cham- ber in the left side of the heart. Sometimes the result of scar tissue forming after a rheumatic fever infection. MITRAL VALVE (mi’tral) Sometimes called bicuspid valve. A valve of two cusps or triangular segments, located between the upper and lower chamber in the left side of the heart. MITRAL VALVULOTOMY (mitral val-vu-lot’o-me) An operation to widen the opening in the valve between the upper and lower chambers in the left side of the heart (mitral valve). Usually performed when the valve open- ing is so narrowed as to obstruct blood flow, which some- times happens as a result of rheumatic fever. 39 ''MONO-UNSATURATED FAT (mon-o-un-sat’u-rat-ed) A fat so constituted chemically that it is capable of ab- sorbing additional hydrogen but not as much hydrogen as a poly-unsaturated fat. These fats in the diet have little effect on the amount of cholesterol in the blood. One example is olive oil. See Poly-unsaturated Fat. MORBIDITY RATE (mor-bid’ i-te) The ratio of the number of cases of a disease to the num- ber of well people in a given population during a speci- fied period of time, such as a year. The term “morbidity” involves two separate concepts. a. Incidence is the number of new cases of a disease de- veloping in a given population during a specified period of time, such as a year. ; b. Prevalence is the number of cases of a given disease existing in a given population at a specified moment of time. MORTALITY RATE—AGE-ADJUSTED (mor-tal’ i-te) Also called age-adjusted death rate. Death rates which have been standardized for age for the purpose of mak- ing comparisons between different populations or within the same population at various intervals of time. The age-specific death rates of the populations being compared are applied to a population that is arbitrarily selected as standard, to determine what would be the crude death rate in the standard population if it were exposed first to the rates of the one population and then to the rates of the other. MORTALITY RATE—AGE-SPECIFIC (mor-tal’i-te) 40 Also called age-specific death rate. The ratio of deaths in a specific age group to the population of the same age group during a given period of time, such as a year. It is calculated by dividing the deaths that occurred among the specific age group during the year by the mid-year population in the same group (estimated popu- lation in the age group on July 1) of the same year. ''MORTALITY RATE—CAUSE-SPECIFIC (mor-tal’i-te) The ratio of deaths from a specific cause to total popu- lation during a given period of time, such as a year. MORTALITY RATE—CRUDE (mor-tal’i-te) The ratio of total deaths to total population during a given period of time, such as a year. Sometimes called crude death rate. It is calculated by dividing the total number of deaths during the year by the mid-year popula- tion (estimated population of July 1) of the same. year. MORTALITY RATE (SPECIFIC-CAUSE-OF-DEATH) (mor-tal'i-te) The number of deaths from a specific cause that occurred in a unit of population (such as per 100,000 or per 10,000 or per 1,000) in a specified time, such as a year. MURMUR (mur’ mur) An abnormal heart sound, sounding like fluid passing an obstruction, heard between the normal lub-dub heart sounds. MYOCARDIAL INFARCTION (mi-o-kar’de-al in-fark’ shun) The damaging or death of an area of the heart muscle (myocardium) resulting from a reduction in the blood supply reaching that area. MYOCARDIAL INSUFFICIENCY (mi-o-kar’de-al) An inability of the heart muscle (myocardium) to main- tain normal circulation. See Congestive Heart Failure. 41 ''~ MYOCARDITIS (mi’o-kar-di’tis) Inflammation of the heart muscle (myocardium). MYOCARDIUM (mi-o-kar’ de-um) The muscular wall of the heart. The thickest of the three layers of the heart wall, it lies between the inner layer (endocardium) and the outer layer (epicardium). NEUROCIRCULATORY ASTHENIA (nu-ro-cir’ cu-lah-to’ re as-the’ne-ah) Sometimes called soldier’s heart or effort syndrome. A complex of nervous and circulatory symptoms, often in- volving a sense of fatigue, dizziness, shortness of breath, rapid heart beat, and nervousness. See Effort Syndrome. NEUROGENIC (nu-ro-jen’ ik) Originating in the nervous system. NEUROSIS (nu-ro’sis) A functional nervous disease in which the personality remains more or less intact. 42 ''NITRITES (ni’trits) A group of chemical compounds, many of which cause dilation of the small blood vessels, and thus lower blood pressure. They are vasodilators. Examples are amyl nitrite, sodium nitrite, etc. NITROGLYCERIN (ni-tro-glis’ er-in) A drug (one of the nitrates) which relaxes the muscles in the blood vessels. Often used to relieve attacks of angina pectoris and spasm of coronary arteries. It is one of the vasodilators. NORADRENALIN (nor-ad-ren’ ah-lin) An organic compound which produces a rise in blood pressure by constricting the small blood vessels. Some- times used in the treatment of shock. Also called nor- epinephrine and levarterenol. NOREPINEPHRINE (nor’ ep-e-nef’ rin) An organic compound which produces a rise in blood pressure by constricting the small blood vessels. Some- times used in the treatment of shock. Also called nor- ~ adrenalin and levarterenol. NORMOTENSIVE (nor-mo-ten’ siv) Characterized by normal blood pressure. NUTRITION (nu-trish’ un) The combination of processes by which a living organism receives and utilizes the materials necessary for the main- tenance of its functions and for the growth and renewal of its components. 43 ''NUTRITIONIST (nu-trish’ un-ist) One professionally engaged in investigating and solving problems of nutrition. OPEN HEART SURGERY Surgery performed on the opened heart while the blood stream is diverted through a heart-lung machine. This machine pumps and oxygenates the blood in lieu of the action of the heart and lungs during the operation. ORGANIC HEART DISEASE Heart disease caused by some structural abnormality in the heart or circulatory system. OSCILLOMETER (os-i-lom’e-ter) An instrument which: measures the. changes in magnitude of the pulsations in the arteries. Especially useful in studying circulation in the periphery of the body. OTITIS MEDIA (0-ti’tis me’ de-ah) An infection of the middle ear, frequently caused by a spreading of a bacterial infection from the throat. '' PACEMAKER (pas’ mak-er) A small mass of specialized cells in the right upper chamber of the heart which give rise to the electrical impulses that initiate contractions of the heart. Also called sino-atrial node or S-A node of Keith-Flack. The term “pacemaker”, or more exactly, “electric cardiac pacemaker”, or “electrical pacemaker” is applied to an electrical device which can substitute for a defective nat- ural pacemaker and control the beating of the heart by a series of rhythmic electrical discharges. If the elec- trodes which deliver the discharges to the heart are placed on the outside of the chest, it is called an “ex- ternal pacemaker”. If the electrodes are placed within the chest wall, it is called an “internal pacemaker”. PALPITATION (pal-pi-ta’ shun) A fluttering of the heart or abnormal rate or rhythm of the heart experienced by the person himself. PANCARDITIS (pan-kar-di'’ tis) Inflammation of the whole heart including inner layer (endocardium), heart muscle (myocardium), and outer sac (pericardium). PAPILLARY MUSCLES (pap’i-ler-e) Small bundles of muscles in the wall of the lower cham- bers of the heart to which the cords leading to the cusps of the valves (chordae tendineae) are attached. When the valves are closed, these muscles contract and tighten the cords which hold the valve firmly shut. 45 ''PARAPLEGIA (par-ah-ple’ je-ah) Loss of both motion and sensation in the legs and lower part of the body. This most commonly is due to dam- age to the spinal cord, but sometimes results from a blood clot or hemorrhage in an artery conducting blood to the spinal cord. PARASYMPATHETIC NERVOUS SYSTEM (par’ ah-sim-pah-thet’ ik) A part of the autonomic or involuntary nervous system. Stimulation of various parasympathetic nerves causes the pupils of the eyes to contract, the heart to beat more slowly, and produces other non-voluntary reactions. PARIETAL PERICARDIUM (pah-ri’e-tal per-e-kar’de-um) A thin membrane sac which surrounds the heart and roots of the great vessels. It is the outer layer of the pericardium. PAROXYSMAL TACHYCARDIA (par-ok-siz’ mal tak-e-kar’ de-ah) A period of rapid heart beats which begins and ends suddenly. PATENT DUCTUS ARTERIOSUS (pa’tent duk’ tus ar-te’re-o’ sis) A congenital heart defect in which a small duct between the artery leaving the left side of the heart (aorta) and the artery leaving the right side of the heart (pulmonary artery), which normally closes soon after birth, remains open. As a result of this duct’s failure to close, blood from both sides of the heart is pumped into the pulmonary artery and into the lungs. This defect is some- times called simply patent ductus. Patent means open. 46 ''PATENT FORAMEN OVALE (pa’ tent fo-ra’men o-va’ le) One type of congenital heart defect. An oval hole be- tween the left and right upper chambers of the heart, which normally closes shortly after birth, remains open. PATHOGENESIS (path-o-jen’e-sis) The chain of events leading to the development of disease. PATHOLOGY (pah-thol’o-je) The study of the essential nature of disease and the structural and functional changes it causes. PERCUSSION (per-kush’ un) Tapping the body as an aid in diagnosing the condition of parts beneath by the sound obtained, much as one taps on a barrel to detect: its fullness. PERICARDITIS (per’e-kar-di’tis) Inflammation of the thin membrane sac (pericardium) which surrounds the heart. PERICARDIUM (per-e-kar’ de-um) A thin membrane sac which surrounds the heart and roots of the great vessels. pericardium 47 ''PERIPHERAL RESISTANCE (peh-rif’er-al) The resistance offered by the arterioles and capillaries to the flow of blood from the arteries to the veins. An in- crease in peripheral resistance causes a rise in blood pressure. PHARMACOLOGY (fahr-mah-kol’o-je) The science which deals with the study of drugs in all its aspects. PHLEBITIS (fle-bi’ tis) Inflammation of a vein, often in the leg. Sometimes a blood clot is formed in the inflamed vein. PHYSICAL THERAPY (ther’ah-pe) The treatment of disease by physical means. Includes the use of heat, cold, water, light, electricity, manipula- tion, massage, exercise, and mechanical devices. Also called physiotherapy. PLASMA (plaz’mah) The cell-free liquid portion of uncoagulated blood. It is different from serum which is the fluid portion of the blood obtained after coagulation. POLYCYTHEMIA (pol’e-si-the’ me-ah) An abnormal condition of the blood characterized by an excessive number of red blood cells. POLYGRAPH (pol’e-graf) An instrument for taking synchronous records of several different pulsations. 48 ''POLY-UNSATURATED FAT (pol-e-un-sat’u-rat-ed) A fat so constituted chemically that it is capable of ab- sorbing additional hydrogen. These fats are usually liquid oils of vegetable origin, such as corn oil or saf- flower oil. A diet with a high poly-unsaturated fat con- tent tends to lower the amount of cholesterol in the blood. These fats are sometimes substituted for saturated fat in a diet in an effort to lessen the hazard of fatty deposits in the blood vessels. See Mono-unsaturated Fat. PRESSOR (pres’or) A substance which raises the blood pressure and acceler- ates the heart beat. Also denotes certain nerve fibers which produce a rise in blood pressure when stimulated. PREVALENCE (prev’ ah-lens) The number of cases of a given disease existing in a given population at a specified moment of time. PRIMARY HYPERTENSION (hi-per-ten’ shun) Sometimes called essential hypertension, and commonly known as high blood pressure. An elevated blood pres- sure not caused by kidney or other evident disease. PROCAINE AMIDE (pro’kan am’ id) A drug sometimes used to treat abnormal rhythms of the heart beat. PROPHYLAXIS (pro-fi-lak’ sis) Preventive treatment. PSYCHOSIS (si-ko’ sis) A severe, specific mental disorder that has a character- istic origin, course, and symptoms. 49 ''PSYCHOSOMATIC (si’ko-so-mat’ ik) Pertaining to the influence of the mind, emotions, fears, etc. upon the functions of the body, especially in relation to disease. PSYCHOTHERAPY (si-ko-ther’ ah-pe) The treatment of disorders by the use of such means as persuasion, suggestion, educational techniques, lay or reli- _gious counseling, or psychoanalysis. ~ PULMONARY ARTERY (pul’mo-na-re) The large artery which con- veys unoxygenated (venous) blood from the lower right chamber of the heart to the lungs. This is the only artery in the body which carries un- oxygenated blood, all others carrying oxygenated blood to the body. pulmonary artery 7 PULMONARY CIRCULATION (pul’mo-na-re) The circulation of the blood through the lungs, the flow being from the right lower chamber of the heart (right ventricle) through the lungs, back to the left upper chamber of the heart (left atrium). See Systemic Crrcula- tion. PULMONARY VALVE (pul’mo-na-re) 50 Valve, formed by three cup- shaped membranes at the junc- tion of the pulmonary artery and the right lower chamber of the heart (right ventricle). When the right lower chamber contracts, the pulmonary valve opens and the blood is forced into the artery leading to the lungs. When the chamber re- laxes, the valve is closed and prevents a back-flow of the blood. ''PULMONARY VEINS (pul’ mo-na-re) Four veins (two from each ee which conduct oxygen- ated blood from the lungs into the left upper chamber of the heart (left atrium). PULSE (puls) The expansion and contraction of an artery which may be felt with the finger. PULSE PRESSURE (puls) The difference between the blood pressure in the arteries when the heart is in contraction (systole) and when it is in relaxation (diastole). PULSUS ALTERNANS (pul’sus aw!l-ter’nans) A pulse in which there is regular alternation of weak and strong beats. PURKINJE FIBERS (pur-kin’ je) Specialized muscular fibers forming a network in the walls of the lower chambers of the heart and believed to be involved in conducting electrical impulses to the mus- cular walls of the two lower chambers (ventricles). These electrical impulses are responsible for the contractions of the heart. 51 '' QUINIDINE (kwin’i-deen) A drug sometimes used to treat abnormal rhythms of the heart beat. RAUWOLFFIA (raw-wol’ fe-ah) A drug consisting of powdered whole root of a plant (Rauwolfia serpentina) which lowers blood pressure and slows the heart rate. Sometimes used in treatment of high blood pressure. An antihypertensive agent. See Reserpine. REGURGITATION (re-gur-ji-ta’ shun) The backward flow of blood through a defective valve. REHABILITATION (re-hah-bil-i-ta’ shun) The return of a person disabled by accident or disease to the maximum attainable physical, mental, emotional, social and economic usefulness, and, if employable, an opportunity for gainful employment. RENAL (re’nal) Pertaining to the kidney. 52 ''RENAL CIRCULATION (re’nal) The circulation of the blood through the kidneys. Im- portant in heart disease because of its function in the elimination of water, certain chemical elements, and waste products from the body. RENAL HYPERTENSION (re’nal hi-per-ten’ shun) High blood pressure caused by damage to or disease of the kidneys. RESERPINE (res’er-peen) One of the organic substances found in the root of the . plant, Rauwolfia serpentina, which lowers blood pressure, slows the heart rate, and has a sedative effect. One of the antihypertensive agents. See Rauwolfia. RHEUMATIC FEVER (ru-mat’ ik) A disease, usually occurring in childhood, which may ~ follow a few weeks after a streptococcal infection. It is sometimes characterized by one or more of the following: fever, sore swollen joints, a skin rash, occasionally by in- voluntary twitching of the muscles (called chorea or St. Vitus Dance) and small nodes under the skin. In some cases the infection affects the heart and may result in scarring the valves, weakening the heart muscle, or damaging the sac enclosing the heart. See Rheumatic Heart Disease. RHEUMATIC HEART DISEASE (ru-mat’ ik) The damage done to the heart, particularly the heart valves, by one or more attacks of rheumatic fever. The valves are sometimes scarred so they do not open and close normally. See Rheumatic Fever. 53 ''RIOLAN, JEAN (1577-1657) Dean of Faculty of Medicine at Paris, a staunch adherent to the old classical (Galen) theory of anatomy, he was one of the most active opponents of William Harvey who discovered the circulation of the blood. HE S-A NODE (nod) A small mass of specialized cells in the right upper chamber of the heart which gives rise to the electrical im- pulses that initiate contractions of the heart. Also called sino-atrial node or pacemaker. SATURATED FAT (sat/u-rat-ed) A fat so constituted chemically that it is not capable of absorbing any more hydrogen. These are usually the solid fats of animal origin such as the fats in milk, butter, meat, etc. A diet high in saturated fat content tends to increase the amount of cholesterol in the blood. Some- times these fats are restricted in the diet in an effort to lessen the hazard of fatty deposits in the blood vessels. SCLEROSIS (skle-ro’sis) Hardening, usually due to an accumulation of fibrous tissue. SECONDARY HYPERTENSION (hi-per-ten’shun) An elevated blood pressure caused by (i.e., secondary to) certain specific. diseases or infections. 54 ''SEDATIVE (sed’ah-tiv) A drug which depresses the activity of the central ner- vous system, thus having a calming effect. Examples are barbiturates, chloral hydrate, and bromides. SEMILUNAR VALVES (sem-e-lu’nar) Cup-shaped valves. The aortic valve at the entrance to the aorta, and the pulmonary valve at the entrance to the pulmonary artery are semilunar valves. They consist of three cup-shaped flaps which prevent the back flow of blood. SEPTUM (sep’tum) A dividing wall. 1. Atrial or inter-atrial septum. Muscular wall dividing left and right upper chambers (called atria) of the heart. 2. Ventricular or inter-ventric- _ ular septum. Muscular wall, thinner at the top, dividing the left and right lower chambers (called ventricles) of the heart. SEROTONIN (ser-o-to’nin) A naturally occurring compound found mainly in the gastrointestinal tract and in lesser amounts in the blood, which has a stimulating effect on the circulatory system. SERUM (se’rum) The fluid portion of blood which remains after the cel- lular elements have been removed by coagulation. It is different from plasma which is the cell-free liquid portion of uncoagulated blood. 55 ''SERVETUS, MICHAEL (1509-1553) Spanish physician who discovered the circulation of the blood through the lungs. Burned at the stake in Geneva for his religious doctrines. SHUNT (shunt) A passage between two blood vessels or between the two sides of the heart, as in cases where an opening exists in the wall which normally separates them. In surgery, the operation of forming a passage between blood vessels to divert blood from one part of the body to another. SIGN Any objective evidence of a disease. See Symptom. SINO-ATRIAL NODE (si-no-a’tre-al) A small mass of specialized cells in the right upper cham- ber of the heart which give rise to the electrical impulses that initiate contractions of the heart. Also called S-A node or pacemaker. SINUSES OF VALSALVA (si’nus-sez of val-sal’vah) Three pouches in the wall of the aorta (main artery lead- ing from left lower chamber of the heart) behind the three cup-shaped membranes of the aortic valve. SODIUM (so’de-um) -A mineral essential to life, found in nearly all plant and animal tissue. ‘Table salt (sodium chloride) is nearly half sodium. In some types of heart disease the body retains an excess of sodium and water, and therefore sodium intake is restricted. 56 ''SPHYGMOMANOMETER (sfig’mo-mah-nom’e-ter) An instrument for measuring blood pressure in the arteries. STASIS (sta’sis) A stoppage or slackening of the blood flow. STENOSIS (ste-no’sis) A narrowing or stricture of an opening. Mitral stenosis, aortic stenosis, etc. means that the valve indicated has become narrowed so that it does not function normally. STETHOSCOPE (steth’o-skdp) An instrument for listening to sounds within the body. STOKES-ADAMS SYNDROME (sin’drom) Sudden attacks of unconsciousness, sometimes with con- vulsions, which may accompany heart block. STROKE (strok) Also called apoplectic stroke, cerebrovascular accident, or cerebral vascular accident. An impeded blood supply to some part of the brain, generally caused by: 57 ''1. a blood clot forming in the vessel (cerebral thrombosis) 2. a rupture of the blood vessel wall (cerebral hemorrhage) 3..a piece of clot or other material from another part of the vascular system which flows to the brain and ob- structs a cerebral vessel (cerebral embolism) 4. pressure on a blood vessel, as by a tumor. STROKE VOLUME (strok) The amount of blood which is pumped out of the heart at each contraction of the heart. SYMPATHECTOMY (sim-pah-thek’to-me) An operation which interrupts some part of the sympa- thetic nervous system. ‘The sympathetic nervous system is a part of the autonomic or involuntary nervous system and normally regulates tissues not under voluntary con- trol, e.g., glands, heart, and smooth muscles. Sometimes the interruption is accomplished by drugs, in which case it is called a chemical sympathectomy. SYMPATHETIC NERVOUS SYSTEM (sim-pah-thet/ik) A part of the autonomic nervous system or involuntary nervous system, it regulates tissues not under voluntary control, e.g., glands, heart, and smooth muscle. See Parasympathetic Nervous System. SYMPTOM (simp’tum) Any subjective evidence of a patient’s condition. See Sign. SYNCOPE (sin’ko-pe) A faint. One cause for syncope can be an insufficient blood supply to the brain. 58 ''SYNDROME (sin’drom) A set of symptoms which occur together and are there- fore given a name to indicate that particular combination. SYSTEMIC CIRCULATION (sis-tem’ik) The circulation of the blood through all parts of the body except the lungs, the flow being from the left lower chamber of the heart (left ventricle) through the body, back to the right upper chamber of the heart (right atrium). See Pulmonary Circulation. SYSTOLE (sis’to-le) In each heart beat, the period of contraction of the heart. Atrial systole is the period of the contraction of the upper chambers of the heart, called the atria. Ventricular systole is the period of the contraction of the lower chambers of the heart, called the ventricles. at TACHYCARDIA (tak-e-kar’de-ah) Abnormally fast heart rate. Generally, anything over 100 beats per minute is considered a tachycardia. TETRALOGY OF FALLOT (te-tral’o-ji of fal-d) A congenital malformation of the heart involving four distinct defects (hence tetralogy). Named for Etienne Fallot, French physician who described the condition in 1888. The four defects are: 59 ''1. an abnormal opening in the wall between the lower chambers of the heart 2. misplacement of the aorta, “over-riding” the abnormal opening, so that it receives blood from both the right and left lower chambers instead of only the left 3. narrowing of the pulmonary artery 4. enlargement of the right lower chamber of the heart. THERAPIST (ther’ah-pist) - A person skilled in the treatment of disease. THIOCYANATE (thi-o-si’ah-nat) ‘A chemical which causes dilation of the small blood ves- sels, thus lowering blood pressure. It is a vasodilator. - THROMBECTOMY (throm-bek’to-me) . An operation to remove a blood clot from a blood vessel. -THROMBOLYTIC AGENTS (throm-bo-lit’ik) .Substance which dissolve blood clots. THROMBOPHLEBITIS (throm’bo-fle-bi’tis) Inflammation and blood clotting in a vein. ~. THROMBOSIS (throm-bo’sis) The formation or..presence of a blood clot (thrombus) inside a blood vessel or cavity of the heart. 60 ''THROMBUS (throm’bus) A blood clot which forms inside a blood vessel or cavity of the heart. See Embolus. THYROTOXIC (thi-ro-tok’ sik) Pertaining to overactivity or abnormal activity of the thyroid gland. TOXEMIA (toks-e’me-ah) The condition caused by poisonous substances in the blood. TOXIC (tok’sik) Pertaining to poison. TRICUSPID VALVE (tri-kus’ pid) A valve consisting of three cusps or triangular segments located between the upper and lower chamber in the right side of the heart. Its position corre- sponds to the bicuspid or mi- tral valve in the left side of the heart. UREMIA (u-re’me-ah) An excess in the blood of certain waste substances nor- mally excreted by the kidneys. 61 '' VAGUS NERVES (va’gus) Two of the nerves of the parasympathetic nervous system which extend from the brain, through the neck and thorax into the abdomen. Known as the inhibitory nerves of the heart, they slow the heart rate when stimulated. VALVULAR INSUFFICIENCY (val’vu-lar) Valves which close improperly and admit a back flow of blood in the wrong direction. See Incompetent Valve. VASOCONSTRICTOR (vas’o-kon-strik’tor) The vasoconstrictor nerves are one part of the involun- tary nervous system. When these nerves are stimulated they cause the muscles of the arterioles to contract, thus narrowing the arteriole passage, increasing the resistance to the flow of blood, and raising the blood pressure. Chemical substances which stimulate the muscles of the arterioles to contract are called vasoconstrictor agents or vasopressors. An example is adrenalin or epinephrine. VASODILATOR (vas’o-di-lat’or) 62 Vasodilator nerves are certain nerve fibers of the involun- tary nervous system which cause the muscles of the arterioles to relax, thus enlarging the arteriole passage, reducing resistance to the flow of blood, and lowering blood pressure. Vasodilator agents are chemical compounds which cause a relaxation of the muscles of the arterioles. Examples of this type of drug are nitroglycerine, nitrites, thiocya- nate, and many others.. ''VASO-INHIBITOR (vas’o-in-hib’i-tor) An agent or drug which inhibits the action of the vaso- motor nerves. When these involuntary nerves are in- hibited, the muscles of the arterioles relax, and the pas- sage inside the arteriole is enlarged, and the blood pressure is lowered. Examples of this type of drug are compounds of nitrite. VASOPRESSOR (vas-o-pres’or) A chemical substance which causes the muscles of the arterioles to contract, narrowing the arteriole passage, and thus raises the blood pressure. Such substances are also called vasoconstrictors. An example is adrenalin or epinephrine. VECTORCARDIOGRAPHY (vek’tor-kar’de-og’rah-fe) Determination of the direction and magnitude of the electrical forces of the heart. VEIN (vain) Any one of a series of vessels of the vascular system which carries blood from various parts of the body back to the heart. All veins in the body conduct unoxygenated blood .except the pulmonary veins which conduct freshly oxy- genated blood from the lungs back to the heart. VENA CAVA (ve’nah ka’vah) Superior vena cava is a large vein conducting blood from the upper part of the body (head, neck, and thorax) to the right upper chamber of the heart. Inferior vena cava is a large vein conducting blood from the lower part of the body to the right upper chamber of the heart. 63 ''VENOUS BLOOD (ve’nus) Unoxygenated blood. The blood, with hemoglobin in the reduced state, is carried by the veins from all parts of the body back to the heart and then pumped by the right side of the heart to the lungs where it is oxygenated. VENTRICLE (ven’tre-kl) One of the two lower chambers of the heart. Left ven- tricle pumps oxygenated blood through arteries to the body. Right ventricle pumps un-oxygenated blood through pulmonary artery to lungs. Capacity about 85 cc. VENTRICULAR SEPTUM (ven-trik’u-lar sep’tum) Sometimes called inter-ventricular septum. Muscular wall, thinner at the top, dividing the left and right lower chambers of the heart which are called ventricles. See Septum. VENULE (ven’ul) A very small vein. VERATRUM (ve-ra’trum) A drug which lowers blood pressure and decreases the heart rate. One of the anti-hypertensive agents. ''VESALIUS, ANDREAS (1514-1564) Belgian anatomist who questioned many of the then cur- rent theories of the circulatory system as taught by Galen, chiefly the existence of openings in the wall divid- ing the left from the right side of the heart through which blood was believed to pass. VISCERAL PERICARDIUM (vis’er-al per-e-kar’de-um) The outer layer of the heart wall. Also called the “epicardium.” AV, WITHERING, WILLIAM (1741-1799) Eminent English clinician who discovered the use and proper dosage of digitalis in the treatment of heart dis- ease. By analyzing the effective herbal mixture used by an old woman in Shropshire, he identified foxglove leaves as the active ingredient which influenced the function of the heart and kidneys. WORK CLASSIFICATION UNIT A community facility involving a team approach to as- sessing the ability of the cardiac patient to work in terms of the energy requirements of the job. 65 '' XANTHINE (zan’thin) A class of drugs used to increase the excretion of urine. A diuretic. U.S. GOVERNMENT PRINTING OFFICE : 1964 OF—714-731 66 '''''' vitae a sh ''Public Health Service Publication No. 1073 ''vIn ''