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Heart, Blood and Circulation Glossary

Terms used to explain Heart, Blood and Circulation can sometimes be confusing. To help you fully understand the articles and features related to this very important health topic, we have compiled a glossary of terms that can help.

ACE Inhibitor

ACE inhibitor
Pronunciation: \ˈās-, ˌā-(ˌ)sē-ˈē-\

Function: noun
: any of a group of antihypertensive drugs (as captopril) that relax arteries and promote renal excretion of salt and water by inhibiting the activity of an angiotensin converting enzyme


Function: noun
: an abnormal person


Function: adjective

1: arising in response to the action of the environment on the organism (as in the use or disuse of an organ) <acquired characteristics> compare genetic 2 hereditary
2: developed after birth <acquired heart murmurs> compare congenital 2 familial hereditary


Pronunciation: \ə-ˈkyüt\

Function: adjective

1: sensing or perceiving accurately, clearly, effectively, or sensitively <acute vision>
2 a: characterized by sharpness or severity <acute pain> <an acute infection>
b (1): having a sudden onset, sharp rise, and short course <an acute disease> <an acute inflammation> compare chronic 2a
(2): see: acute care<an acute hospital>
c: lasting a short time <acute experiments>


Pronunciation: \al-ˈdäs-tə-ˌrōn; ˌal-dō-ˈsti(ə)r-ˌōn, -stə-ˈrōn\

Function: noun
: a steroid hormone C21H28O5 of the adrenal cortex that functions in the regulation of the salt and water balance of the body


Function: noun
: an abnormal blood-filled dilatation of a blood vessel and esp. an artery resulting from disease of the vessel wall


Pronunciation: \an-ˈjī-nə, ˈan-jə-\

Function: noun
: a disease marked by spasmodic attacks of intense suffocative pain: as
a: a severe inflammatory or ulcerated condition of the mouth or throat <diphtheritic angina> see ludwig's angina vincent's angina
b: see: angina pectoris


Pronunciation: \ˈan-jē-ə-ˌgram\

Function: noun

1: a radiograph made by angiography
2: see: angiography


Pronunciation: \ˈan-jē-ə-ˌplas-tē\

Function: noun
pl -ties
: surgical repair or recanalization of a blood vessel; esp: see: balloon angioplasty


Pronunciation: \ˌant-ē-ˈäk-səd-ənt, ˌan-ˌtī-\

Function: noun
: any of various substances (as beta-carotene, vitamin C, and alpha-tocopherol) that inhibit oxidation or reactions promoted by oxygen and peroxides and that include many held to protect the living body from the deleterious effects of free radicals

Aplastic Anemia

aplastic anemia
Function: noun
: anemia that is characterized by defective function of the blood-forming organs (as the bone marrow) and is caused by toxic agents (as chemicals or X-rays) or is idiopathic in origin —called also hypoplastic anemia


Pronunciation: \ā-ˈrith-mē-ə\

Function: noun
: an alteration in rhythm of the heartbeat either in time or force


Pronunciation: \är-ˌtir-ē-ō-sklə-ˈrō-səs\

Function: noun
pl -ro*ses
Pronunciation: \-ˌsēz\
: a chronic disease characterized by abnormal thickening and hardening of the arterial walls with resulting loss of elasticity compare atherosclerosis



Pronunciation: \ˈärt-ə-rē\

Function: noun

pl -ter*ies

1: any of the tubular branching muscular- and elastic-walled vessels that carry blood from the heart through the body


Pronunciation: \ˈas-p(ə-)rən\

Function: noun
pl aspirin
or aspirins

1: a white crystalline derivative C9H8O4 of salicylic acid used for relief of pain and fever
2: a tablet of aspirin



Pronunciation: \ˌath-ə-rō-sklə-ˈrō-səs\

Function: noun

pl -ro*ses

1: an arteriosclerosis characterized by atheromatous deposits in and fibrosis of the inner layer of the arteries


Pronunciation: \ˈā-trē-əm\

Function: noun
pl atria
Pronunciation: \-trē-ə\
also atri*ums
: an anatomical cavity or passage; esp: a chamber of the heart that receives blood from the veins and forces it into a ventricle or ventricles


Function: abbreviation
benign prostatic hyperplasia; benign prostatic hypertrophy

Balloon Angioplasty

balloon angioplasty
Function: noun
: dilation of an obstructed atherosclerotic artery by the passage of a balloon catheter through the vessel to the area of disease where inflation of the catheter's tip compresses the plaque against the vessel wall

Blood Count

blood count
Function: noun
: the determination of the blood cells in a definite volume of blood; also: the number of cells so determined see complete blood count differential blood count


Pronunciation: \ˈkab-ij\

Function: abbreviation
coronary artery bypass graft


Function: abbreviation
coronary artery disease


Function: abbreviation
complete blood count


Function: abbreviation
congestive heart failure


Function: abbreviation
cardiopulmonary resuscitation


Function: abbreviation
cardiovascular disease


Function: symbol


Pronunciation: \ˌkärd-ē-ˈäl-ə-jē\

Function: noun
pl -gies
: the study of the heart and its action and diseases


Pronunciation: \ˈkärd-ē-ō-(ˌ)mī-ˈäp-ə-thē\

Function: noun
pl -thies
: any structural or functional disease of heart muscle that is marked esp. by hypertrophy of cardiac muscle, by enlargement of the heart, by rigidity and loss of flexibility of the heart walls, or by narrowing of the ventricles but is not due to a congenital developmental defect, to coronary atherosclerosis, to valve dysfunction, or to hypertension


Pronunciation: \ˌkärd-ē-ō-ˈpul-mə-ˌner-ē, -ˈpəl-\

Function: adjective
: of or relating to the heart and lungs <the cardiopulmonary system> <a cardiopulmonary bypass that diverts blood from the entrance to the right atrium through an oxygenator directly to the aorta>


Pronunciation: \-ˈvas-kyə-lər\

Function: adjective

1: of, relating to, or involving the heart and blood vessels <cardiovascular[1] disease>
2: used, designed, or performed to cause a temporary increase in heart rate (as to improve heart function and reduce the risk of heart disease) <a cardiovascular[1] workout> <treadmills, stationary bicycles, and other cardiovascular[1] equipment>


Pronunciation: \kə-ˈles-tə-ˌrōl, -ˌrol\

Function: noun
1: a steroid alcohol C27H45OH present in animal cells and body fluids that regulates membrane fluidity, functions as a precursor molecule in various metabolic pathways, and as a constituent of LDL may cause arteriosclerosis


Pronunciation: \ˈkrän-ik\

Function: adjective

1 a: marked by long duration, by frequent recurrence over a long time, and often by slowly progressing seriousness : not acute <chronic[1] indigestion> <her hallucinations became chronic[1]>
b: suffering from a disease or ailment of long duration or frequent recurrence <a chronic[1] arthritic> <chronic[1] sufferers from asthma>
2 a: having a slow progressive course of indefinite duration used esp. of degenerative invasive diseases, some infections, psychoses, and inflammations <chronic[1] heart disease> <chronic[1] arthritis> <chronic[1] tuberculosis> compare acute 2b(1)
b: infected with a disease-causing agent (as a virus) and remaining infectious over a long period of time but not necessarily expressing symptoms <chronic[1] carriers may remain healthy but still transmit the virus causing hepatitis B>


Pronunciation: \ˌkī-lō-ˈmī-ˌkrän\

Function: noun
1: a lipoprotein rich in triglyceride and common in the blood during fat digestion and assimilation


Pronunciation: \ˈklät-ˌbəs-tər\

Function: noun
: a drug (as streptokinase or tissue plasminogen activator) used to dissolve blood clots

Coronary Artery

coronary artery
Function: noun
: either of two arteries that arise one from the left and one from the right side of the aorta immediately above the semilunar valves and supply the tissues of the heart itself

Coronary Artery Disease

coronary artery disease
Function: noun
: a condition and esp. one caused by atherosclerosis that reduces the blood flow through the coronary arteries to the heart muscle and typically results in chest pain or heart damage —called also coronary disease, coronary heart disease


Pronunciation: \ˌsī-ə-ˈnō-səs\

Function: noun
pl -no*ses
Pronunciation: \-ˌsēz\
: a bluish or purplish discoloration (as of skin) due to deficient oxygenation of the blood


Pronunciation: \(ˌ)dē-ˌfib-rə-ˈlā-shən, -ˌfīb-\

Function: noun
: restoration (as by an electric shock) of the rhythm of a fibrillating heart


Pronunciation: \ˌdē-t(y)ü-ˈmes-ən(t)s\

Function: noun
: subsidence or diminution of swelling or erection


Pronunciation: \ˌdī-ə-ˈbēt-ēz, -ˈbēt-əs\

Function: noun
pl diabetes
: any of various abnormal conditions characterized by the secretion and excretion of excessive amounts of urine; esp: see: diabetes mellitus

Diastolic Blood Pressure

diastolic blood pressure
Function: noun
: the lowest arterial blood pressure of a cardiac cycle occurring during diastole of the heart —called also diastolic pressure, compare systolic blood pressure


Pronunciation: \ˌdī-(y)ə-ˈret-ik\

Function: adjective
: tending to increase the excretion of urine


Pronunciation: \dis-ˈrith-mē-ə\

Function: noun

1: an abnormal rhythm; esp: a disordered rhythm exhibited in a record of electrical activity of the brain or heart
2: see: jet lag


Function: abbreviation


Pronunciation: \ˌē-ˌkā-ˈjē\

Function: noun

1: see: electrocardiogram
2: see: electrocardiograph


Pronunciation: \-ˌkärd-ē-ˈäg-rə-fē\

Function: noun
pl -phies
: the use of ultrasound to examine and measure the structure and functioning of the heart and to diagnose abnormalities and disease


Function: noun
pl -mas
also -ma*ta
Pronunciation: \-mət-ə\

: an abnormal excess accumulation of serous fluid in connective tissue or in a serous cavity —called also dropsy


Pronunciation: \-ˈkärd-ē-ə-ˌgram\

Function: noun
: the tracing made by an electrocardiograph; also: the procedure for producing an electrocardiogram


Pronunciation: \ˈem-bə-ˌliz-əm\

Function: noun

1: the sudden obstruction of a blood vessel by an embolus
2: see: embolus


Pronunciation: \ˌem(p)-fə-ˈzē-mə, -ˈsē-\
Function: noun
1: a condition characterized by air-filled expansions in interstitial or subcutaneous tissues; specif: a condition of the lung that is marked by distension and eventual rupture of the alveoli with progressive loss of pulmonary elasticity, that is accompanied by shortness of breath with or without cough, and that may lead to impairment of heart action


Pronunciation: \ˌen-dō-ˌkär-ˈdīt-əs\

Function: noun
: inflammation of the lining of the heart and its valves


Function: noun
: a colorless crystalline feebly basic sympathomimetic hormone C9H13NO3 that is the principal blood-pressure-raising hormone secreted by the adrenal medulla, is prepared from adrenal extracts or made synthetically, and is used medicinally esp. as a heart stimulant, as a vasoconstrictor (as to treat open-angle glaucoma and life-threatening allergic reactions and to prolong the effects of local anesthetics), and as a bronchodilator —called also adrenaline


Pronunciation: \i-ˈrek-shən\

Function: noun

1: the state marked by firm turgid form and erect position of a previously flaccid bodily part containing cavernous tissue when that tissue becomes dilated with blood
2: an occurrence of erection in the penis or clitoris


Function: symbol


Pronunciation: \(ˌ)fər-ˈtil-ət-ē\

Function: noun
pl -ties

1: the quality or state of being fertile
2: the birthrate of a population compare mortality 2b


Pronunciation: \ˌfib-rə-ˈlā-shən, ˌfīb-\

Function: noun

1: an act or process of forming fibers or fibrils
2 a: a muscular twitching involving individual muscle fibers acting without coordination
b: very rapid irregular contractions of the muscle fibers of the heart resulting in a lack of synchronism between heartbeat and pulse see atrial fibrillation ventricular fibrillation


Pronunciation: \ˈflas-əd, ˈflak-səd\

Function: adjective
: not firm or stiff; also: lacking normal or youthful firmness <flaccid muscles>


Pronunciation: \ˈāch-ˈdē-ˈel\
Function: noun
1: a lipoprotein of blood plasma that is composed of a high proportion of protein with little triglyceride and cholesterol and that is associated with decreased probability of developing atherosclerosis —called also alpha-lipoprotein, good cholesterol, high-density lipoprotein

Heart Attack

heart attack
Function: noun
: an acute episode of heart disease marked by the death or damage of heart muscle due to insufficient blood supply to the heart muscle usu. as a result of a coronary thrombosis or a coronary occlusion and that is characterized esp. by chest pain —called also myocardial infarction, compare angina pectoris coronary insufficiency heart failure 1

Heart Disease

Function: noun
1: an abnormal organic condition of the heart or of the heart and circulation

Heart Rate

heart rate
Function: noun
: a measure of cardiac activity usu. expressed as number of beats per minute see maximum heart rate

High Blood Pressure

high blood pressure
Function: noun
: see: hypertension


Function: noun
1: the presence of excess fat or lipids in the blood


Pronunciation: \ˈhī-pər-ˌten-chən\

Function: noun

1: abnormally high arterial blood pressure that is usu. indicated by an adult systolic blood pressure of 140 mm Hg or greater or a diastolic blood pressure of 90 mm Hg or greater, is chiefly of unknown cause but may be attributable to a preexisting condition (as a renal or endocrine disorder), that typically results in a thickening and inelasticity of arterial walls and hypertrophy of the left heart ventricle, and that is a risk factor for various pathological conditions or events (as heart attack, heart failure, stroke, end-stage renal disease, or retinal hemorrhage) see essential hypertension secondary hypertension white coat hypertension
2: a systemic condition resulting from hypertension that is either symptomless or is accompanied esp. by dizziness, palpitations, fainting, or headache


Function: abbreviation
International Classification of Diseases usu. used with a number indicating the revision<ICD-9>


Pronunciation: \ˌī-byu-ˈprō-fən\

Function: noun
: a nonsteroidal anti-inflammatory drug C13H18O2 used in over-the-counter preparations to relieve pain and fever and in prescription strength esp. to relieve the symptoms of rheumatoid arthritis and degenerative arthritis see advil motrin


Pronunciation: \ˈim-pət-ən(t)s\

Function: noun

1: the quality or state of not being potent <drug-resistant bacteria are a virulent indicator of the growing impotence of antibiotics>
2: an abnormal physical or psychological state of a male characterized by inability to copulate because of failure to have or maintain an erection —called also erectile dysfunction

Iron-deficiency Anemia

iron–deficiency anemia
Function: noun
: anemia that is caused by a deficiency of iron and characterized by hypochromic microcytic red blood cells


Function: noun
: deficient supply of blood to a body part (as the heart or brain) that is due to obstruction of the inflow of arterial blood (as by the narrowing of arteries by spasm or disease)


Pronunciation: \ˈel-ˈdē-ˈel\

Function: noun
1: a lipoprotein of blood plasma that is composed of a moderate proportion of protein with little triglyceride and a high proportion of cholesterol and that is associated with increased probability of developing atherosclerosis —called also bad cholesterol, beta-lipoprotein, low-density lipoprotein, compare hdl vldl


Pronunciation: \lə-ˈbēd-(ˌ)ō also ˈlib-ə-ˌdō or lə-ˈbī-(ˌ)dō\

Function: noun
pl -dos

1: instinctual psychic energy that in psychoanalytic theory is derived from primitive biological urges (as for sexual pleasure or self-preservation) and that is expressed in conscious activity
2: sexual drive


Pronunciation: \ˈlip-əd\

Function: noun
1: any of various substances that are soluble in nonpolar organic solvents (as chloroform and ether), that with proteins and carbohydrates constitute the principal structural components of living cells, and that include fats, waxes, phospholipids, cerebrosides, and related and derived compounds


Pronunciation: \-ˈprō-ˌtēn, -ˈprōt-ē-ən\

Function: noun
1: any of a large class of conjugated proteins composed of a complex of protein and lipid see hdl ldl vldl

Malignant Hypertension

malignant hypertension
Function: noun
: essential hypertension characterized by acute onset, severe symptoms, rapidly progressive course, and poor prognosis

Metabolic Syndrome

Function: noun
1: a syndrome marked by the presence of usu. three or more of a group of factors (as high blood pressure, abdominal obesity, high triglyceride levels, low HDL levels, and high fasting levels of blood sugar) that are linked to an increased risk of cardiovascular disease and type 2 diabetes —called also insulin resistance syndrome, syndrome X

Mitral Valve

mitral valve
Function: noun
: a valve in the heart that guards the opening between the left atrium and the left ventricle, prevents the blood in the ventricle from returning to the atrium, and consists of two triangular flaps attached at their bases to the fibrous ring which surrounds the opening and connected at their margins with the ventricular walls by the chordae tendineae and papillary muscles —called also bicuspid valve, left atrioventricular valve

Myocardial Infarction

myocardial infarction
Function: noun
: see: heart attack


Pronunciation: \ˈnī-ə-sən\

Function: noun
1: a crystalline acid C6H5NO2 that is a member of the vitamin B complex occurring usu. in the form of a complex of niacinamide in various animal and plant parts (as blood, liver, yeast, bran, and legumes) and is effective in preventing and treating human pellagra and blacktongue of dogs —called also nicotinic acid

Nitric Oxide

nitric oxide
Function: noun
: a poisonous colorless gas NO that occurs as a common air pollutant formed by the oxidation of atmospheric nitrogen and that is also formed by the oxidation of arginine in the mammalian body where it acts as a mediator of intracellular and intercellular communication regulating numerous biological processes (as vasodilation and neurotransmission)


Pronunciation: \ō-ˈbē-sət-ē\

Function: noun
pl -ties
: a condition that is characterized by excessive accumulation and storage of fat in the body and that in an adult is typically indicated by a body mass index of 30 or greater


Pronunciation: \-ˈthrē\

Function: adjective
1: being or composed of polyunsaturated fatty acids in which the first double bond in the hydrocarbon chain occurs between the third and fourth carbon atoms from the end of the molecule most distant from the carboxylic acid group and which are found esp. in fish (as tuna and salmon), fish oils, green leafy vegetables, and some vegetable oils


Pronunciation: \ˈor-ˌgaz-əm\

Function: noun
: the climax of sexual excitement that is usu. accompanied by ejaculation of semen in the male and by vaginal contractions in the female


Pronunciation: \ˌäk-sə-ˈdā-shən\

Function: noun

1: the act or process of oxidizing
2: the state or result of being oxidized


Pronunciation: \ˌpal-pə-ˈtā-shən\

Function: noun
: a rapid pulsation; esp: an abnormally rapid beating of the heart when excited by violent exertion, strong emotion, or disease


Pronunciation: \ˌpaŋ-krē-ə-ˈtīt-əs, ˌpan-\

Function: noun
1: inflammation of the pancreas


Pronunciation: \-ˌkär-ˈdīt-əs\

Function: noun
pl -dit*i*des
Pronunciation: \-ˈdit-ə-ˌdēz\
: inflammation of the pericardium see adhesive pericarditis


Function: noun
pl -nea
also -naea
Pronunciation: \-ˈnē-ə\

: an area of tissue that marks externally the approximate boundary of the pelvic outlet and gives passage to the urogenital ducts and rectum; also: the area between the anus and the posterior part of the external genitalia esp. in the female

Peyronie's Disease

Pey*ro*nie's disease
Pronunciation: \ˌpā-rə-ˈnēz-, pā-ˈrō-(ˌ)nēz-\

Function: noun
: the formation of fibrous plaques in one or both corpora cavernosa of the penis resulting in distortion or deflection of the erect organ


Pronunciation: \ˈplur-ə-sē\

Function: noun
pl -sies
: inflammation of the pleura that is typically characterized by sudden onset, painful and difficult respiration, and exudation of fluid or fibrinous material into the pleural cavity —called also pleuritis, see dry pleurisy wet pleurisy


Pronunciation: \ˌn(y)ü-mə-ˈthō(ə)r-ˌaks, -ˈtho(ə)r-\

Function: noun
pl -tho*rax*es
or -tho*ra*ces
Pronunciation: \-ˈthōr-ə-ˌsēz\
: a condition in which air or other gas is present in the pleural cavity and which occurs spontaneously as a result of disease or injury of lung tissue, rupture of air-filled pulmonary cysts, or puncture of the chest wall or is induced as a therapeutic measure to collapse the lung see tension pneumothorax compare oleothorax


Pronunciation: \ˌpäl-ē-ˌən-ˈsach-ə-ˌrāt-əd\

Function: adjective
of an oil, fat, or fatty acid
: having in each molecule many chemical bonds in which two or three pairs of electrons are shared by two atoms compare monounsaturated


Pronunciation: \ˈprī-ə-ˌpiz-əm\

Function: noun
: an abnormal, more or less persistent, and often painful erection of the penis; esp: one caused by disease rather than sexual desire


Function: adjective
: of, relating to, or being the prostate gland


Pronunciation: \ˈpul-mə-ˌner-ē, ˈpəl-\

Function: adjective
: relating to, functioning like, associated with, or carried on by the lungs

Pulmonary Artery

pulmonary artery
Function: noun
: an arterial trunk or either of its two main branches that carry oxygen-deficient blood to the lungs:
a: a large arterial trunk that arises from the conus arteriosus of the right ventricle, ascends in front of the aorta, and branches into the right and left pulmonary arteries —called also pulmonary trunk
b: a branch of the pulmonary trunk that passes under the arch of the aorta to the right lung where it divides into branches —called also right pulmonary artery
c: a branch of the pulmonary trunk that passes to the left in front of the descending part of the aorta, gives off the ductus arteriosus in the fetus which regresses to the ligamentum arteriosum in the adult, and passes to the left lung where it divides into branches —called also left pulmonary artery

Pulse Pressure

pulse pressure
Function: noun
: the pressure that is characteristic of the arterial pulse and represents the difference between diastolic and systolic blood pressures of the heart cycle


Pronunciation: \ˈrē-nən also ˈren-ən\

Function: noun
: a proteolytic enzyme of the blood that is produced and secreted by the juxtaglomerular cells of the kidney and hydrolyzes angiotensinogen to angiotensin I


Pronunciation: \ri-ˌsəs-ə-ˈtā-shən, rē-\

Function: noun
: an act of resuscitating or the state of being resuscitated <resuscitation by means of artificial respiration or cardiac massage> see cardiopulmonary resuscitation

S-A Node

S–A node
Pronunciation: \ˌes-ˈā-\

Function: noun
: see: sinoatrial node


Pronunciation: \ˈskrōt-əm\

Function: noun
pl scro*ta
Pronunciation: \-ə\>
or scrotums
: the external sac that in most mammals contains the testes

Secondary Hypertension

secondary hypertension
Function: noun
: hypertension that results from an underlying identifiable cause (as aldosteronism, thyroid dysfunction, or coarctation of the aorta)


Pronunciation: \ˈsē-mən\

Function: noun
: a viscid whitish fluid of the male reproductive tract consisting of spermatozoa suspended in secretions of accessory glands (as of the prostate and Cowper's glands)

Sinus Node

sinus node
Function: noun
: see: sinoatrial node


Pronunciation: \ˈstat-ən\

Function: noun
1: any of a group of drugs (as lovastatin and simvastatin) that inhibit the synthesis of cholesterol and promote the production of LDL-binding receptors in the liver resulting in a usu. marked decrease in the level of LDL and a modest increase in the level of HDL circulating in blood plasma


Pronunciation: \stə-ˈnō-səs\

Function: noun
pl -no*ses
Pronunciation: \-ˌsēz\
: a narrowing or constriction of the diameter of a bodily passage or orifice <esophageal stenosis> see aortic stenosis mitral stenosis pulmonary stenosis spinal stenosis subaortic stenosis


Pronunciation: \ˈstrōk\

Function: noun
1: sudden diminution or loss of consciousness, sensation, and voluntary motion caused by rupture or obstruction (as by a clot) of a blood vessel of the brain —called also apoplexy, brain attack, cerebral accident, cerebrovascular accident

Systolic Blood Pressure

systolic blood pressure
Function: noun
: the highest arterial blood pressure of a cardiac cycle occurring immediately after systole of the left ventricle of the heart —called also systolic pressure, compare diastolic blood pressure


Pronunciation: \te-ˈstäs-tə-ˌrōn\

Function: noun
: a male hormone that is a crystalline hydroxy steroid ketone C19H28O2 produced primarily by the testes or made synthetically and that is the main androgen responsible for inducing and maintaining male secondary sex characteristics


Pronunciation: \thräm-ˈbō-səs, thrəm-\

Function: noun
pl -bo*ses
Pronunciation: \-ˌsēz\
: the formation or presence of a blood clot within a blood vessel see coronary thrombosis deep vein thrombosis

Trans Fat

trans fat
Function: noun
: a fat containing trans-fatty acids

Tricuspid Valve

tricuspid valve
Function: noun
: a valve that is situated at the opening of the right atrium of the heart into the right ventricle and that resembles the mitral valve in structure but consists of three triangular membranous flaps —called also right atrioventricular valve


Pronunciation: \(ˈ)trī-ˈglis-ə-ˌrīd\

Function: noun
: any of a group of lipids that are esters formed from one molecule of glycerol and three molecules of one or more fatty acids, are widespread in adipose tissue, and commonly circulate in the blood in the form of lipoproteins —called also neutral fat


Pronunciation: \ˈəl-trə-ˌsaund\

Function: noun

1: vibrations of the same physical nature as sound but with frequencies above the range of human hearing compare infrasound
2: the diagnostic or therapeutic use of ultrasound and esp. a noninvasive technique involving the formation of a two-dimensional image used for the examination and measurement of internal body structures and the detection of bodily abnormalities —called also echography, sonography, ultrasonography
3: a diagnostic examination using ultrasound


Pronunciation: \yu-ˈrē-thrə\
Function: noun
1: the canal that in most mammals carries off the urine from the bladder and in the male serves also as a passageway for semen


Pronunciation: \ˌvā-zō-ˈdī-ˌlāt-ər\

Function: noun
: an agent (as a parasympathetic nerve fiber or a drug) that induces or initiates vasodilation

Ventricular Assist Device

ventricular as*sist device
Pronunciation: \-ə-ˈsist-\

Function: noun
: see: vad

Ventricular Tachycardia

ventricular tachycardia
Function: noun
: tachycardia that is associated with the generation of electrical impulses within the ventricles and is characterized by an electrocardiogram having a broad QRS complex abbr. VT,V-tach


Pronunciation: \zan-ˈthō-mə\

Function: noun
1: a fatty irregular yellow patch or nodule containing lipid-filled foam cells that occurs on the skin (as of the eyelids, neck, or back) or in internal tissue and is associated esp. with disturbances of lipid metabolism

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