CARDIOVASCULAR SYSTEM

cardiovascular system

consists of the pump and vessels that distribute blood to all areas of the body. This system allows for the delivery of needed substances to the cells of the body as well as for the removal of wastes.

blood vessels and heart

The primary structures that comprise the cardiovascular system:

arteries, capillaries, veins

3 components of blood vessels

heart

Pumps blood through blood vessels

artery

Carries blood away from the heart

vein

Carries blood toward the heart

capillary

Exchange site between blood and tissues

arteries

carries blood with oxygen

arteries

carries oxygenated blood

circulatory system

maintains the distribution of blood throughout the body and is composed of the heart and the blood vessels—arteries, capillaries, and veins.

pulmonary and systemic circulation

circulatory system is composed of two parts: the

pulmonary circulation

between the heart and lungs, transports deoxygenated blood to the lungs to get oxygen, and then back to the heart.

systemic circulation

carries oxygenated blood away from the heart to the tissues and cells, and then back to the heart

oxygen

distributing —— and other nutrients, such as glucose and amino acids, the cardiovascular system also collects the waste products from the body’s cells.

carbon dioxide

and other waste products produced by metabolic reaction are transported by the cardiovascular system to the lungs, liver, and kidneys, where they are eliminated from the body.

heart

a muscular pump made up of cardiac muscle fibers, could be consid- ered a muscle rather than an organ.

60–100 beats per minute

average beats oh heart per minute

mediastinum

The heart is located in the ———in the center of the chest cavity; however, it is not exactly centered

endocardium

is the inner layer of the heart lining the heart chambers. It is a very smooth, thin layer that serves to reduce friction as the blood passes through the heart chambers.

myocardium

is the thick, muscular middle layer of the heart. Contrac- tion of this muscle layer develops the pressure required to pump blood through the blood vessels.

epicardium

the outer layer of the heart. The heart is enclosed within a double-layered pleural sac, called the pericardium. The epicardium is the visceral pericardium, or inner layer of the sac. The outer layer of the sac is the parietal pericardium. Fluid between the two layers of the sac reduces friction as the heart beats.

pulmonary,aortic,mitral,tricuspid valve

4 chambers or cavities of the heart

interatial septum

heart chambers are divided into right and left sides by walls called the

four valves

act as restraining gates to control the direction of blood flow. They are situated at the entrances and exits to the ventricles

little belly

The term ventricle comes from the Latin term venter, which means ——

tricuspid valve

an atrioventricular valve (AV), meaning that it controls the opening between the right atrium and the right ventricle. Once the blood enters the right ventricle, it cannot go back up into the atrium again. The prefix tri-, meaning three, indicates that this valve has three leaflets or cusps.

pulmonary valve

a semilunar valve, with the prefix semi- meaning half and the term lunar meaning moon, indicate that this valve looks like a half moon. Located between the right ventricle and the pulmonary artery, this valve prevents blood that has been ejected into the pulmonary artery from returning to the right ventricle as it relaxes.

mitral valve

also called the bicuspid valve, indicating that it has two cusps. Blood flows through this atrioventricular valve to the left ventricle and cannot go back up into the left atrium.

aortic valve

a semilunar valve located between the left ventricle and the aorta. Blood leaves the left ventricle through this valve and cannot return to the left ventricle.

superior vena cava and inferior vena cava.

Deoxygenated blood from all the tissues in the body enters a relaxed right atrium via two large veins called the

right atrium

contracts and blood flows through the tricuspid valve into the relaxed right ventricle.

pulmonary artery

The right ventricle then contracts and blood is pumped through the pul- monary valve into the ———, which carries it to the lungs for oxygenation.

pulmonary veins

The left atrium receives blood returning to the heart after being oxygen- ated by the lungs. This blood enters the relaxed left atrium from the four ———

left atrium

contracts and blood flows through the mitral valve into the relaxed left ventricle.

aorta

When the left ventricle contracts, the blood is pumped through the aortic valve and into the —-, the largest artery in the body. The aorta carries blood to all parts of the body.

diastole, systole

It can be seen that the heart chambers alternate between relaxing, in order to fill, and contracting to push blood forward. The period of time a chamber is relaxed is ——. The contraction phase is ——.

autonomic nervous system

heart rate is regulated by the ————therefore, there is no voluntary control over the beating of the heart.

sinoatrial (SA, S-A) node or pacemaker

where the electrical impulses begin. From the sinoatrial node, a wave of electricity travels through the atria, causing them to contract, or go into systole.

apex

The tip of the heart at the lower edge is called the

atrioventricular bundle

node transfers the stimulation wave to the—-

bundle branches

The electrical signal next travels down the ——-within the interventricular septum.

purkinje fibers

The ——- out in the ventricular myocardium are stimulated,

blood vessels

pipes that circulate blood throughout the body

lumen

is the channel within these vessels through which blood flows.

arteries

are the large, thick-walled vessels that carry the blood away from the heart.

coronary arteries

The ——- then branch from the aorta and provide blood to the myocardium

capillary bed

Capillaries are a network of tiny blood vessels referred to as a ——

veins

carry blood back to the heart

small venules

Blood leaving capillaries first enters ——, which then merge into larger veins.

veins

have much thinner walls than arteries, causing them to collapse easily

blood pressure

is a measurement of the force exerted by blood against the wall of a blood vessel.

systolic pressure

During ventricular systole, blood is under a lot of pressure from the ventricular contraction, giving the highest blood pressure reading—the

pulse

felt at the wrist or throat is the surge of blood caused by the heart contraction

diastolic pressure

blood is not being pushed by the heart at all and the blood pressure reading drops to its lowest point—the

cardiology

Branch of medicine involving diagnosis and (kar-dee-ALL-oh-jee) -logy = study of treatment of conditions and diseases of cardio-vascular system; physician is a cardiologist

cardiovascular technologist/technician

Healthcare professional trained to perform variety of diagnostic and therapeutic procedures including electrocardiography, echocardiography, and exercise stress tests

angiitis

Inflammation of a vessel

angiostenosis

Narrowing of a vessel

embolus

Obstruction of blood vessel by blood clot that has broken off from thrombus somewhere else in body and traveled to point of obstruction; if it occurs in coronary artery, may result in myocar- dial infarction

regurgitation

To flow backward; in cardiovascular system this refers to backflow of blood through a valve

thrombus

Blood clot forming within blood vessel; may partially or completely occlude blood vessel

angina pectoris

Condition in which there is severe pain with sensation of constriction around heart; caused by deficiency of oxygen to heart muscle; commonly called chest pain (CP)

cardiac arrest

Complete stopping of heart activity

infarct

Area of tissue within organ or part that under goes necrosis (death) following loss of its blood supply

ischemia

Localized and temporary deficiency of blood supply due to obstruction to circulation

murmur

A sound, in addition to normal heart sounds arising from blood flowing through heart; extrasound may or may not indicate a heart abnormality

orthostatic hypotension

Sudden drop in blood pressure a person experiences when standing straight up suddenly

palpitations

Pounding, racing heartbeats

cardiac tamponade

Pressure on heart as a result of fluid buildup pertaining to around heart inside pericardial sac; heart becomes unable to pump blood effectively

cardiomegaly

enlarged heart

cardiomyopathy

General term for disease of myocardium; can be caused by alcohol abuse, parasites, viral infection, and congestive heart failure; one of most common reasons a patient may require heart transplant

congenital septal defect

Hole, present at birth, in septum between two heart chambers; results in mixture of oxygenated and deoxygenated blood; can be an atrial septal defect (ASD) and a ventricular septal defect (VSD)

congestive heart failure (CHF)

Pathological condition of heart in which there is reduced outflow of blood from left side of heart because left ventricle myocardium has become too weak to efficiently pump blood; results in weakness, breathlessness, and edema

coronary artery disease

Insufficient blood supply to heart muscle dueto obstruction of one or more coronary arteries; may be caused by atherosclerosis and may cause angina pectoris and myocardial infarction

endocarditis

Inflammation of lining membranes of heart; may be due to bacteria or to abnormal immu- nological response; in bacterial endocarditis, mass of bacteria that forms is referred to as vegetation

heart valve prolapse

Condition in which cusps or flaps of heart valve are too loose and fail to shut tightly, allowing blood to flow backward through valve when heart chamber contracts; most commonly occurs in mitral valve, but may affect any of heart valves; also called heart valve incompetence or heart valve insufficiency

heart valve stenosis

Condition in which cusps or flaps of heart valve are too stiff and are unable to open fully (making it difficult for blood to flow through) or shut tightly (allowing blood to flow backward); condition may affect any of heart valves

myocardial infarction

Condition caused by partial or complete occlusion or closing of one or more of coronary arteries; symptoms include squeezing pain or heavy pressure in middle of chest (angina pectoris); delay in treatment could result in death; also referred to as a heart attack;

myocarditis

Inflammation of muscle layer of heart wall

pericarditis

Inflammation of pericardial sac around heart

tetralogy of fallot

Combination of four congenital anomalies: pulmonary stenosis, interventricular septaldefect, improper placement of aorta, and hypertrophy of right ventricle; needs immediate surgery to correct

valvulitis

Inflammation of a heart valve

arrythmia

Irregularity in heartbeat or action; comes in many different forms; may be too fast, too slow,or irregular pattern; some are not serious, while others are life-threatening

bundle branch block

Occurs when electrical impulse is blocked from traveling down bundle of His or bundle branches; results in ventricles beating at different rate than atria; also called a heart block

bradycardia

Condition of having a slow heart rate, typical less than 60 beats/minute; highly trained aerobic persons may normally have a slow heart rate

fibrillation

Extremely serious arrhythmia characterized by abnormal quivering or contraction of heart fibers; when this occurs in ventricles, cardiac arrest and death can occur; emergency equip- ment to defibrillate, or convert heart to normal beat, is necessary

flutter

Arrhythmia in which atria beat too rapidly, but in regular pattern

premature atrial contraction

Arrhythmia in which atria contract earlier than they should

premature ventricular contraction

Arrhythmia in which ventricles contract earlier than they should

tachycardia

Condition of having a fast heart rate, typically more than 100 beats/minute while at rest

aneurysm

Weakness in wall of artery resulting in localized widening of artery; although aneurysm may develop in any artery, common sites include aorta in abdomen and cerebral arteries in brain

arteriorrhexis

Ruptured artery; may occur if aneurysm ruptures arterial wall

arteriosclerosis

Thickening, hardening, and loss of elasticity hardening of walls of arteries; most often due to atherosclerosis

atheroma

Deposit of fatty substance in wall of artery that bulges into and narrows lumen of artery; characteristic of atherosclerosis; also called a plaque

atherosclerosis

caused by formation of yellowish plaques of cholesterol on inner walls of arteries

coarctation of the aorta

Severe congenital narrowing of aorta

deep vein thrombosis

Formation of blood clot in a vein deep in the body, most commonly the legs; embolus breaking off from this thrombosis would travel to lungs and block blood flow through lungs

hemorrhoid

Varicose veins in anal region

hypertension

Blood pressure (BP) above normal range; essential or primary hypertension occurs directly from cardiovascular disease; secondary hypertension refers to high blood pressure resulting from another disease such as kidney disease

hypotension

Decrease in blood pressure (BP); can occur in shock, infection, cancer, anemia, or as death approaches