Chapter 17 - Cardiovascular system

Question 1

What is the cardiovascular system?

Answer 1

A system of organs that carries materials around the body. Things carried include oxygen nutrients from digestive system, hormones, and waste materials.

Question 2

What is the heart?

Answer 2

An organ made of mostly cardiac tissue that pumps the blood.
The heart has 4 chambers:
1. right atrium
2. right ventricle
3. left atrium
4. left ventricle

Question 3

Anatomy of the heart

Answer 3

Aorta
Aortic valve
Pulmonary artery
Pulmonary valve
Right atrium
Left atrium
Right ventricle
Left ventricle
Mitral valve
Tricuspid valve

Question 4

What are blood vessels comparable to?

Answer 4

The blood vessels of the cardiovascular system are like a network of interconnected, one-way roads that range from superhighways to back alleys. Like a network of roads, the blood vessels have the job of allowing the transport of materials from one place to another. There are three major types of blood vessels: arteries, veins, and capillaries.

Question 5

What are arteries?

Answer 5

Arteries are blood vessels that carry blood away from the heart (except for the arteries that actually supply blood to the heart muscle). Most arteries carry oxygen-rich blood, and one of their main functions is distributing oxygen to tissues throughout the body. The smallest arteries are called arterioles.

Question 6

What are veins?

Answer 6

Veins are blood vessels that carry blood toward the heart. Most veins carry deoxygenated blood. The smallest veins are called venules.

Question 7

What are capillaries?

Answer 7

Capillaries are the smallest blood vessels. They connect arterioles and venules. As they pass through tissues, they exchange substances including oxygen with cells.

Question 8

What are the 2 blood circulations?

Answer 8

The pulmonary circulation involves only the heart and lungs and the major blood vessels that connect them. . .Blood moves through the pulmonary circulation from the heart, to the lungs, and back to the heart again, becoming oxygenated in the process.

Systemic Circulation: The oxygenated blood that enters the left atrium of the heart in the pulmonary circulation then passes into the systemic circulation. This is the part of the cardiovascular system that transports blood to and from all of the tissues of the body to provide oxygen and nutrients and pick up wastes.

Question 9

What is the body’s largest artery?

Answer 9

The Aorta

Question 10

Is blood a connective tissue? Y/N?

Answer 10

Yes!
Blood is a fluid connective tissue that circulates throughout the body in blood vessels by the pumping action of the heart. Blood carries oxygen and nutrients to all the body’s cells, and it carries carbon dioxide and other wastes away from the cells to be excreted. Blood also transports many other substances, defends the body against infection, repairs body tissues, and controls the body’s pH, among other functions.

Question 11

Functions of blood

Answer 11

-Carry oxygen + Nutrients + Carbon Dioxide
-Transports various substances
-Defends body against infection
-Repair body tissues
-Control pH

Question 12

How big is a normal adult human heart?

Answer 12

A normal adult heart is about the size of a fist.

Question 13

How many layers makeup the wall of the heart?

Answer 13

The wall of the heart is made up of three layers, called the endocardium, myocardium, and pericardium.

Question 14

What is the endocardium?

Answer 14

The endocardium is the innermost layer of the heart wall. It is made up primarily of simple epithelial cells. It covers the heart chambers and valves. A thin layer of connective tissue joins the endocardium to the myocardium.

Question 15

What is the myocardium?

Answer 15

The myocardium is the middle and thickest layer of the heart wall. It consists of cardiac muscle surrounded by a framework of collagen. There are two types of cardiac muscle cells in the myocardium: pacemaker cells, which have the ability to contract easily; and pacemaker cells, which conduct electrical impulses that cause the cardiomyocytes to contract. About 99 percent of cardiac muscle cells are cardiomyocytes, and the remaining 1 percent is pacemaker cells. The myocardium is supplied with blood vessels and nerve fibers via the pericardium.

Question 16

What is the epicardium?

Answer 16

The epicardium is the third layer which is a part of pericardium, a protective sac that encloses and protects the heart. The pericardium consists of two membranes (visceral pericardium called epicardium and parietal pericardium), between which there is a fluid-filled cavity. The fluid helps to cushion the heart and also lubricates its outer surface.

Question 17

Another name for ventricles:

Answer 17

Discharging chambers.

The ventricles are also referred to as discharging chambers because blood leaving the heart passes out through these two chambers. The right ventricle discharges blood to the lungs through the pulmonary artery, and the left ventricle discharges blood to the rest of the body through the aorta.

Question 18

What separates the 4 chambers of the heart?

Answer 18

Dense connective tissue made mostly of collagen.

Question 19

How many valves does the heart have?

Answer 19

4

tricuspid valve, which allows blood to flow from the right atrium to the right ventricle.

mitral valve, which allows blood to flow from the left atrium to the left ventricle.

pulmonary valve, which allows blood to flow from the right ventricle to the pulmonary artery.

aortic valve, which allows blood to flow from the left ventricle to the aorta.

Question 20

What is another name for the tricuspid and mitral valves?

Answer 20

The tricuspid and mitral valves are also called atrioventricular (or AV) valves because they are found between the atrium and the ventricle.

Question 21

What is another name for the pulmonary and aortic valves?

Answer 21

The pulmonary and aortic valves are also called semilunar valves because they are shaped like half-moons.

Question 22

What do coronary arteries do?

Answer 22

Coronary arteries supply oxygen-rich blood to the heart muscle cells.

Question 23

What do coronary veins do?

Answer 23

Coronary veins remove deoxygenated blood from the heart muscles cells.

Question 24

What is the cardiac cycle?

Answer 24

The cardiac cycle refers to a single complete heartbeat, which includes one iteration of the lub and dub sounds heard through a stethoscope. During the cardiac cycle, the atria and ventricles work in a coordinated fashion so that blood is pumped efficiently through and out of the heart. The cardiac cycle includes two parts, called diastole and systole.

Question 25

What are the 2 parts of the Cardiac cycle?

Answer 25

Diastole and Systole

During diastole, the atria contract and pump blood into the ventricles, while the ventricles relax and fill with blood from the atria.

During systole, the atria relax and collect blood from the lungs and body, while the ventricles contract and pump blood out of the heart.

Question 26

What is the normal, rhythmic beating of the heart called?

Answer 26

The Sinus Rhythm.

Question 27

What makes the Sinus Rhythm?

Answer 27

The normal, rhythmic beating of the heart is called sinus rhythm. It is established by the heart’s pacemaker cells in the sinoatrial node. Electrical signals from the pacemaker cells travel to the atria and cause them to contract. Then the signals travel to the atrioventricular node and from there to the ventricles, causing them to contract. Electrical stimulation from the autonomic nervous system and hormones from the endocrine system can also influence heartbeat.

Question 28

Why are veins called capacitance blood vessels?

Answer 28

Veins are called capacitance blood vessels because the majority (about 60 percent) of the body’s total volume of blood is contained within veins.

Question 29

2 largest veins in body?

Answer 29

The two largest veins in the body are the superior vena cava, which carries blood from the upper body directly to the right atrium of the heart, and the inferior vena cava, which carries blood from the lower body directly to the right atrium.

Question 30

What are the smallest veins in the body called?

Answer 30

Venules

Question 31

What are the smallest blood vessels in the body?

Answer 31

Capillaries are the smallest blood vessels in the cardiovascular system. They are so small that only one red blood cell at a time can squeeze through a capillary, and then only if the red blood cell deforms. Capillaries connect arterioles and venules. . .Capillaries generally form a branching network of vessels, called a capillary bed, that provides a large surface area for the exchange of substances between the blood and surrounding tissues.

Question 32

What is a lumen?

Answer 32

Not a measurement of brightness in this case!

A lumen in the body is the internal space within a blood vessel through which blood flows.

Question 33

What are the 3 layers of the walls of arteries and veins?

Answer 33

The Tunica Intima
The Tunica Media
The Tunica Externa

Question 34

What is the tunica intima?
A. a tight greek tunic
B. the inner layer of arteries and veins.

Answer 34

B

Question 35

What is the Tunica Intima?

Answer 35

The tunica intima is the inner layer of arteries and veins. It is also the thinnest layer, consisting of a single layer of endothelial cells surrounded by a thin layer of connective tissues. It reduces friction between the blood and the inside of the blood vessel walls.

Question 36

What is the Tunica Media?

Answer 36

The tunica media is the middle layer of arteries and veins. In arteries, this is the thickest layer. It consists mainly of elastic fibers and connective tissues. In arteries, this is the thickest layer because it also contains smooth muscle tissues, which control the diameter of the vessels.

Question 37

What is the Tunica Externa?

Answer 37

The tunica externa (also called tunica adventitia) is the outer layer of arteries and veins. It consists of connective tissue and also contains nerves. In veins, this is the thickest layer. In general, the tunica externa protects and strengthens vessels and attaches them to surrounding structures.

Question 38

What is the thickest layer of an artery wall?

Answer 38

Tunica Media

Question 39

What is the thickest layer of a vein wall?

Answer 39

Tunica Externa

Question 40

Capillary walls

Answer 40

The walls of capillaries consist of little more than a single layer of epithelial cells. Being just one cell thick, the walls are well suited for the exchange of substances between the blood inside them and the cells of surrounding tissues. Substances including water, oxygen, glucose, and other nutrients as well as waste products such as carbon dioxide can pass quickly and easily through the extremely thin walls of capillaries.

Question 41

Blood Pressure!!!

Answer 41

Blood pressure is a measure of the force that blood exerts on the walls of arteries. It is generally measured in millimeters of mercury (mm Hg) and expressed as a double number: a higher number for systolic pressure when the ventricles contract; and a lower number for diastolic pressure when the ventricles relax. Normal blood pressure is generally defined as less than 120 mm Hg (systolic)/80 mm Hg (diastolic) when measured in the arm at the level of the heart. It decreases as blood flows farther away from the heart and into smaller arteries.

Question 42

What would happen if blood pressure DID NOT reduce as it traveled into veins and capillaries?

Answer 42

As arteries grow smaller, there is increasing resistance to blood flow through them because of friction of the blood against the arterial walls. This resistance restricts blood flow so less blood reaches smaller, downstream vessels, thus reducing blood pressure before the blood flows into the tiniest vessels, the capillaries. Without this reduction in blood pressure, capillaries would not be able to withstand the pressure of the blood without bursting.

Question 43

Pressure of blood in veins
(See context in textbook)

Answer 43

The pressure of blood against the walls of veins is always about the same and normally no more than 10 mm Hg.

Question 44

Vasoconstriction and Vasodilation

Answer 44

Smooth muscles in the walls of arteries can contract or relax to cause vasoconstriction (narrowing of the lumen of blood vessels) or vasodilation (widening of the lumen of blood vessels). This allows the arteries — especially the arterioles — to contract or relax as needed to help regulate blood pressure

Question 45

Blood is quite literally, the ____ of ____

Answer 45

elixir, life

Question 46

Functions of blood

Answer 46

Blood performs many important functions in the body. Major functions of blood include:

supplying tissues with oxygen, which is needed by all cells for aerobic cellular respiration.
supplying cells with nutrients, including glucose, amino acids, and fatty acids.
removing metabolic wastes from cells, including carbon dioxide, urea, and lactic acid.
helping to defend the body from pathogens and other foreign substances.
forming clots to seal broken blood vessels and stop bleeding.
transporting hormones and other messenger molecules.
regulating the pH of the body, which must be kept within a narrow range (7.35 to 7.45).
helping to regulate body temperature (through vasoconstriction and vasodilation).

Question 47

What are the 3 formed elements of blood?

Answer 47

Red blood cells, white blood cells, platelets

Question 48

The cytoplasm of a mature ____ is almost ____ filled with ____

Answer 48

RBC, completely, Hemoglobin

Question 49

Categories and Types of WBC’s:

Answer 49

There are two categories of WBCs, granulocytes (contain visible granules in cytoplasm) and agranulocytes (do not contain granules). The Granulocytes include neutrophils, eosinophils, and basophils. The agranulocytes include lymphocytes and monocytes. The five types differ in their specific immune functions. The relative percent and functions of WBCs are summarized in the following table:

Question 50

Good way to remember platelets and fibrin:

Answer 50

Coagulation begins almost instantly after an injury to the endothelium of a blood vessel occurs. Platelets become activated and change their shape from spherical to star-shaped, as shown in the figure below. This helps them aggregate with one another at the site of injury to start forming a plug in the vessel wall. Activated platelets also release substances into the blood that activate additional platelets and start a sequence of reactions leading to fibrin formation. Strands of fibrin crisscross the platelet plug and strengthen it, much as rebar strengthens concrete.

Question 51

Why is blood considered a type of connective tissue?

Answer 51

Blood is considered to be a connective tissue because blood cells form inside bones. All three types of blood cells are made in red marrow within the medullary cavity of bones in a process called hematopoiesis.

Question 52

Stem cells and blood

Answer 52

Formation of blood cells occurs by the proliferation of stem cells in the marrow. These stem cells are self-renewing: when they divide, some of the daughter cells remain stem cells, so the pool of stem cells is not used up. Other daughter cells follow various pathways to differentiate into the variety of types of blood cells. Once the cells have differentiated, they cannot divide to form copies of themselves

Question 53

What is Leukemia?

Answer 53

Leukemia is a group of cancers of the blood-forming tissues in the bone marrow. It is the most common type of cancer in children, although most cases occur in adults. Leukemia is generally characterized by large numbers of abnormal white blood cells. Symptoms may include excessive bleeding and bruising, fatigue, fever, and an increased risk of infections. Leukemia is thought to be caused by a combination of genetic and environmental factors.

Question 54

What is Hemophilia?

Answer 54

Hemophilia refers to any of several genetic disorders that cause dysfunction in the blood clotting process. People with hemophilia are prone to potentially uncontrollable bleeding even with otherwise inconsequential injuries. They also commonly suffer bleeding into the spaces between joints, which can cause crippling.

Question 55

What is Carbon Monoxide Poisoning?

Answer 55

Carbon monoxide poisoning occurs when inhaled carbon monoxide (for example, in fumes from a faulty home furnace) binds irreversibly to the hemoglobin in red blood cells. As a result, oxygen cannot bind to the red cells for transport throughout the body, and this can quickly lead to suffocation. Carbon monoxide is extremely dangerous because it is colorless and odorless so it cannot be detected in the air by human senses.

Question 56

What is HIV?

Answer 56

HIV is a virus that infects certain types of white blood cells and interferes with the body’s ability to defend itself from pathogens and other causes of illness. HIV infection may eventually lead to AIDS, or acquired immunodeficiency syndrome. AIDS is characterized by rare infections and cancers that people with a healthy immune system almost never acquire.

Question 57

What is Anemia?

Answer 57

Anemia is a disorder in which the blood has an inadequate volume of red blood cells. This reduces the amount of oxygen that the blood can carry and may cause weakness and fatigue. These and other signs and symptoms of anemia are shown in the figure below. Anemia has many possible causes, including excessive bleeding, inherited disorders such as sickle cell hemoglobin, or nutritional deficiencies (iron, folate, or B12). Severe anemia may require transfusions of donated blood.

Question 58

What is a blood type?

Answer 58

Blood type (or blood group) is a genetic characteristic associated with the presence or absence of certain molecules, called antigens, on the surface of red blood cells. These molecules may help maintain the integrity of the cell membrane, act as receptors, or have other biological functions.

Question 59

What is a blood group system?

Answer 59

A blood group system refers to all of the gene(s), alleles, and possible genotypes and phenotypes that exist for a particular set of blood type antigens. Human blood group systems include the well-known ABO and Rhesus (Rh) systems, as well at least 33 others that are less well known

Question 60

ANTIGENS:

Answer 60

Antigens such as those on the red blood cells are molecules that the immune system identifies as either self (produced by your own body) or nonself (not produced by your own body). Blood group antigens may be proteins, carbohydrates, glycoproteins (proteins attached to chains of sugars), or glycolipids (lipids attached to chains of sugars), depending on the particular blood group system. If antigens are identified as nonself, the immune system responds by forming antibodies that are specific to the nonself antigens.

Question 61

ANTIBODIES:

Answer 61

Antibodies are large, Y-shaped proteins produced by the immune system that recognize and bind to nonself antigens. . .Nonself antigens may enter your body on pathogens such as bacteria or viruses, on foods, or on red blood cells in a blood transfusion from someone with a different blood type than your own. The last way is virtually impossible nowadays because of effective blood typing and screening protocols.

Question 62

Analogy for antigens and antibodies

Answer 62

The analogy of a lock and key is often used to represent how an antibody and antigen fit together, as shown in the illustration below. When antibodies bind to antigens, it marks them for destruction by other immune system cells.

Question 63

Can blood type change???

Answer 63

Like other genetic traits, a person’s blood type is generally fixed for life, but there are rare instances in which blood type can change. This could happen, for example, if an individual receives a bone marrow transplant to treat a disease such as leukemia. If the bone marrow comes from a donor who has a different blood type, the patient’s blood type may eventually convert to the donor’s blood type because red blood cells are produced in bone marrow.

Question 64

Names of RBC antigen molecules:

Answer 64

N acetyl-galactosamine
N acetyl-glucosamine
Fucose
Galactose

Question 65

The ABO blood group system is controlled by a single gene on chromosome ____.

Answer 65

9

Question 66

There are how many possible genotypes and phenotypes for the ABO blood group?

Answer 66

6 genotypes
-IA IA
-IAi
-IBIB
-IBi
-ii
-IAIB

4 possible phenotypes:
-A
-B
-O
-AB

Question 67

Which blood group is most important in blood transfusions?

Answer 67

The ABO system

Question 68

What does agglutinate mean?

Answer 68

Clump and break apart

Question 69

What happens if to a recipient if they get the wrong blood type donated to them?

Answer 69

If a unit of incompatible blood were to be accidentally transfused into a patient, a severe reaction (called acute hemolytic transfusion reaction) is likely to occur in which many red blood cells are destroyed. This may result in kidney failure, shock, and even death. Fortunately, such medical accidents virtually never occur today.

Question 70

Universal donor?

Answer 70

Type O blood contains both anti-A and anti-B antibodies, so people with type O blood can only receive type O blood. However, they can donate blood to people of any ABO blood type. That’s why individuals with type O blood are called universal donors.

Question 71

Universal recipient?

Answer 71

Type AB blood contains neither anti-A nor anti-B antibodies, so people with type AB blood can receive blood from people of any ABO blood type. That’s why individuals with type AB blood are called universal recipients. However, they can donate blood only to people who also have type AB blood.

Question 72

Rhesus system:

Answer 72

The Rhesus system has dozens of different antigens but only five main antigens (named D, C, c, E, and e). The major Rhesus antigen is the D antigen. People with the D antigen are called Rh positive (Rh+), and people who lack the D antigen are called Rh negative (Rh-). Rhesus antigens are thought to play a role in transporting ions across cell membranes by acting as channel proteins.

Question 73

The rhesus blood group system is controlled by ___ linked genes on chromosome ___.

Answer 73

two, 1

Question 74

HDN

Answer 74

Unlike antibodies against ABO antigens, antibodies against the Rhesus D antigen can cross the placenta and enter the blood of the fetus. This may cause hemolytic disease of the newborn (HDN), also called erythroblastosis fetalis, an illness in which fetal red blood cells are destroyed by maternal antibodies, causing anemia. This illness may range from mild to severe. If it is severe, it may cause brain damage and is sometimes fatal for the fetus or newborn. Fortunately, HDN can be prevented by preventing the formation of anti-D antibodies in the Rh- mother. This is achieved through an injection into the mother of a medication called Rho(D) immune globulin.

Question 75

Precursors of Cardiovascular Disease:

Answer 75

There are two very common conditions that are precursors to virtually all cases of cardiovascular disease: hypertension, or high blood pressure; and atherosclerosis, commonly called hardening of the arteries. Both conditions affect the arteries and their ability to maintain normal blood flow.

Question 76

What is Hypertension?

Answer 76

Hypertension is a chronic medical condition in which the blood pressure in the arteries is persistently elevated. . .High blood pressure is classified as either primary or secondary high blood pressure. At least 90 percent of cases are primary high blood pressure, which is caused by some combination of genetic and lifestyle factors. Numerous genes have been identified as having small effects on blood pressure. Lifestyle factors that increase the risk of high blood pressure include excess dietary salt and alcohol consumption in addition to the risk factors for cardiovascular disease stated above. Secondary high blood pressure, which makes up the remaining 10 percent of cases of hypertension, is attributable to a particular identifiable cause, such as chronic kidney disease or an endocrine disorder such as Cushing’s disease.

Question 77

Atherosclerosis:

Answer 77

Atherosclerosis is a condition in which artery walls thicken and stiffen as a result of the buildup of plaques inside the arteries. Plaques consist of white blood cells, cholesterol, and other fats. Typically, there is also a proliferation of smooth muscle cells that make the plaque fibrous as well as fatty. Over time, the plaques may harden with the addition of calcium crystals. This reduces the elasticity of the artery walls. As plaques increase in size, the artery walls dilate to compensate so blood flow is not affected. Eventually, however, the lumen of the arteries is likely to become so narrowed by plaque buildup that blood flow is reduced or even blocked entirely

Question 78

Coronary Artery Disease

Answer 78

Coronary artery disease is a group of diseases that result from atherosclerosis of coronary arteries. Treatment of the diseases mainly involves treating the underlying atherosclerosis. Two of the most common coronary artery diseases are angina and myocardial infarction.

Question 79

Angina

Answer 79

Angina is chest pain or pressure that occurs when heart muscle cells do not receive adequate blood flow and become starved of oxygen (a condition called ischemia). . .There may also be pain in the back, neck, shoulders, or jaw; and in some cases, the pain may be accompanied by shortness of breath, sweating, or nausea.

Question 80

Two types of Angina:

Answer 80

Stable angina is angina in which pain is precipitated by exertion (say, from brisk walking or running) and improves quickly with rest or the administration of nitroglycerin, which dilates coronary arteries and improves blood flow. Stable angina may develop into unstable angina.

Unstable angina is angina in which pain occurs during rest, lasts more than 15 minutes, and is of new onset. This type of angina is more dangerous and may be a sign of an imminent heart attack. It requires urgent medical attention.

Question 81

What the heck is a Myocardial Infarction? Yes, Infarction, not INFRACTION.

Answer 81

A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow stops to part of the heart causing damage to the heart muscle and the death of myocardial cells. As shown in the figure below, an MI usually occurs because of complete blockage of a coronary artery, often due to a blood clot or the rupture of a plaque. . .An MI typically causes chest pain and pressure, among other possible symptoms, but at least one quarter of MIs do not cause any symptoms. . .

In the worst case, an MI may cause sudden death. Even if the patient survives, an MI often causes permanent damage to the heart. This puts the heart at risk of heart arrhythmias, heart failure, and cardiac arrest.

Heart arrhythmias are abnormal heart rhythms, which are potentially life threatening. Heart arrhythmias often can be interrupted with a cardiac defibrillator, which delivers an electrical shock to the heart, in effect “rebooting” it.
Heart failure occurs when the pumping action of the heart is impaired so tissues do not get adequate oxygen. This is a chronic condition that tends to get worse over time, although it can be managed with medications.
Cardiac arrest occurs when the heart no longer pumps blood or pumps blood so poorly that vital organs can no longer function. This is a medical emergency requiring immediate intervention.

Question 82

STROKE

Answer 82

A stroke, also known as a cerebrovascular accident or brain attack, occurs when blocked or broken arteries in the brain result in the death of brain cells. There are two main types of stroke, both of which are illustrated below: ischemic stroke and hemorrhagic stroke.

An ischemic stroke occurs when an embolus (blood clot) breaks off from a plaque or forms in the heart because of arrhythmia and travels to the brain where it becomes lodged in an artery. This blocks blood flow to the part of the brain that is served by arteries downstream from the blockage. Lack of oxygen causes the death of brain cells. Treatment with a clot-busting drug within a few hours of the stroke may prevent permanent damage. Almost 90 percent of strokes are ischemic strokes.
A hemorrhagic stroke occurs when an artery in the brain ruptures and causes bleeding in the brain. This deprives downstream tissues of adequate blood flow and also puts pressure on brain tissue. Both factors can lead to the death of brain cells. Surgery to temporarily open the cranium may be required to relieve the pressure. Only about 10 percent of strokes are hemorrhagic strokes, but they are more likely to be fatal than ischemic strokes.

Question 83

STROKES: Things to know

Answer 83

In both types of stroke, the part of the brain that is damaged loses is ability to function normally. Signs and symptoms of stroke may include an inability to move, feel, or see on one side of the body; problems understanding speech or difficulty speaking; memory problems; confusion; and dizziness. Hemorrhagic strokes may also cause a severe headache. The symptoms of stroke usually occur within seconds or minutes of the brain injury. Depending on the severity of the stroke and how quickly treatment is provided, the symptoms may be temporary or permanent. If the symptoms of a stroke go away on their own in less than an hour or two, the stroke is called a transient ischemic attack. Stroke is the leading cause of disability in the United States, but rehabilitation with physical, occupational, speech or other types of therapy may significantly improve functioning.

The main risk factor for stroke is high blood pressure. Therefore, keeping blood pressure within the normal range, whether with lifestyle changes or medications, is the best way to reduce the risk of stroke. Another possible cause of stroke is the use of illicit drugs such as amphetamines or cocaine. Having had a stroke in the past greatly increases one’s risk of future strokes. Men are also more likely than women to have strokes.

Question 84

What is PAD?

Answer 84

Peripheral artery disease (PAD) is narrowing of the arteries other than those that supply the heart or brain due to atherosclerosis.