Chapter 15: Cardiovascular System

What does Angiotensin-converting enzyme (ACE) inhibitors do?

(block formation of angiotenisin II) --> Prevent vasoconstriction

Vein valves

- function to keep blood flowing towards the heart - also act as blood reservoirs

What are the steps of the pulmonary circuit?

1. Blood enters pulmonary circuit as it leaves right ventricle into pulmonary trunk 2. The pulmonary trunk divides into left and right pulmonary arteries --> lungs 3. In lungs, blood reaches capillary beds as arterioles (Low O | High CO2) 4. Gases are exchanged between blood and air as blood passes through the alveolar capillaries 5. Blood now enters venules (High O | Low CO2) and merges into veins 6. Pulmonary veins return blood to left atrium - circuit complete

What are the three types of layers of the heart wall?

1. Endocardium 2. Myocardium 3. Pericardium

What are the steps of the systemic circuit?

1. Fresh oxygenated blood moves from left atrium to left ventricle 2. Contraction of left ventricle forces blood to enter systemic circuit 3. Blood reaches aorta which sends blood to all body tissues as well as companion system and returns blood to right atrium

Where are the common places to detect pulse?

1. Radial artery 2. Brachial artery 3. Carotid artery 4. Temporal artery 5. facial artery 6. femoral artery 7. popliteal artery 8. posterior tibial artery

What are the three layers of an artery? What are they made of?

1. Tunica Intima (Endothelium) - To provide smooth surface for blood flow and prevent clotting 2. Tunica Media - composed of smooth muscle fibers 3. Tunica Adventitia - Connective tissue with collagenous and elastic fibers

How does mid-to late diastole work? This cardiac period is first, second, or third?

1. starts with heart at complete relax state where blood pressure is low and blood is flowing into and through atria into ventricle (ventricular filling) 1.Av valves open and semilunar valves close 2. Causes atria to contract (atrial systole) - SA NODES FIRE causing blood remaining blood (30%) in atria to go into ventricles First

What % flows passively from atria to ventricles? How is the remaining pushed?

70%. The remaining is pushed when the atria contracts which causes A-V to close

What is another name of the tricuspid and mitral valves? Why?

A-V valves. Because they are located between the atria and ventricles.

What is a murmur?

An abnormal heart sound

What are the five types of blood vessels?

Arteries, arterioles, capillaries, venules, veins

What happens when ventricles contract?

Atria relax

Why do the ventricular walls contract with a twisting motion? What kind of motion does this produce?

Because muscle fibers in wall form irregular whorls. It produces a pushing motion.

Where is the atrioventicular sulcus located?

Between the atria and the ventricles

Where is the pulmonary valve located? When does it open?

Between the right ventricle and pulmonary trunk. It opens when the right ventricle contracts.

What does the systemic circuit consist of?

Blood vessels that carry blood from the heart to all the parts of the body and back again

What does the pulmonary circuit consist of?

Blood vessels that carry blood from the heart to the lungs and back to the heart

What kind of blood goes through the heart and how?

Blood with low oxygen and rich in carbon dioxide... 1. enter the right atrium through the superior and inferior venae cavae as well as through the coronary sinus. 2. Right atrium contracts, blood goes to the right ventricle. 3.Right ventricle contracts, blood goes into pulmonary trunk. 4. From the pulmonary arteries it enters the lungs where the blood looses its CO2 and gains Oxygen. 5. Blood returns to heart via pulmonary veins into the left atrium. 6. Left atrium contracts, blood goes to left ventricle. 7. Left ventricle contracts, blood makes it into the aorta.

How do the impulses travel to the A-V node? Where do they go from there?

By the conducting fibers. It then goes to the A-V bundle.

What do arteries do?

Conduct blood away from the heart and into arterioles

What do venules and veins do?

Conduct blood from capillaries into the heart

The cardiac conduction system is responsible for...?

Coordinating events of cardiac cycle

What is the pericardium?

Covering the encloses the heart

What do calcium channel blockers do?

Dialate blood vessels by keeping Ca ions out of muscle cells in vessel walls

When does the dupp sound occur?

During ventricular diastole, when pulmonary and aortic valves close

When does the lubb sound occur?

During ventricular systole when the A-V valves close

From where does the right atrium receive blood?

From superior and inferior vena cavae and coronary sinus

Where does blood come from in the right atrium?

From the right coronary artery it goes into 2 arteries posterior interventricular artery then into the ventricular walls and marginal artery into the walls of the right atrium and right ventricle from the left coronary artery it goes into 2 arteries circumflex artery then to the walls of left atrium and left ventricle all of these go into the cardiac veins which will then go into the coronary sinus into the right atrium

Where does the right ventricle received blood?

From the right ventricle

What happens after impulses reach the AV Node? Where is this structure located? What does this structure give?

Impulses make their way into the AV-Bundle (Bundle of His) The Bundle of his is located in the superior part of the interventricular septum It gives rise to bundle branches (left and right) that carry action potential to the Purkinje Fibers

Where are capillaries most protected?

In the brain

Where are the Purkinje fibers located? What is the purpose of the Purkinje Fibers?

In the inferior portion of the interventricular septum, papillary muscles, and in the ventricular walls To carry impulses to distant regions of the ventricular myocardium Help ventricles contract (twisting motion)

Where are the most permeable capillaries located?

In the sleep, liver, and red bone marrow

What is the purpose of Diuretics?

Increase urine output, lowering blood volume

What factor does temperature play in heart rate? Who has a higher heart rate?

Increased temperature leads to increased heart rate Decreased temperature leads to decreased heart rate Females - slightly

Endocardium is also know as the...? Composed of what?

Inner layer and composed of epithelium and connective tissue with manly elastic and collagenous fibers (Purkinje fibers)

What is systolic pressure?

Is is the max pressure and is created when ventricles contract

What is vasodilation? When does it occur?

Is is the relaxation of smooth muscle cells in the walls of blood vessels. When blood vessel diameter increases.

Where does blood from left atrium go?

It goes to left ventricle

Where is the aortic valve located? When does it open?

It is located between the left ventricle and the aorta. It opens when the left ventricle contracts.

What is vasoconstriction?

It is the contraction of smooth muscle cells in blood vessel walls

What are the characteristics of the Aorta?

It is the largest in diameter artery in the body. It extends upwards from the left ventricle, arches over the heart to the left and descends behind and the the left of the vertical column

What is diastolic pressure?

It is the min pressure and is created when ventricles relax

What is the fibrous pericardium?

It is the outer fibrous layer

What is stroke volume?

It is the volume of blood discharged from the ventricle with one contraction

What is cardiac output?

It is the volume of blood discharged from ventricle per minute

Where does contraction start? Where does blood go?

It starts at apex (tip-bottom of heart). Pushes blood upwards towards aortic and pulmonary semilunar valves.

What is the location of the mitral (bicuspid) valve? What's its function?

Its located between the left atrium and left ventricle. It helps prevent back flow into the left atrium.

Where is the tricuspid valve located? What's its function?

Located between the right atrium and right ventricle. Its function is to prevent blood to flow back into the right atrium.

Where is the AV - Node (atrio-ventricular node) located? What happens here? Where does the action go to?

Located in right atrium, in the inferior part of the interatrial septum. Conducting fibers deliver impulses from the S-A node to the A-V node Impulses are delayed as they come to A-V node, giving time for atria to contract and ventricles to fill up

Where is the A-V Bundle? (Bundle of His) and what's its function?

Located in the top part of the inter-ventricular septum. It gives rise to bundle branches

Where is the S-A node located? What does it initiate? S-A node is also known as the...?

Located in the wall of right atrium. It initiates one impulse after another. Also known as the pacemaker

What is the purpose of Beta blockers?

Lower heart rate

Myocardium is also known as the...? Composed of what?

Middle layer and composed of cardiac muscle tissue

The pulmonary trunk divides into what? What is their function?

Pulmonary Arteries. They deliver blood to the lungs.

Heart is in beneath what rib?

Second rib

Pulmonary and aortic valves are also known as? Why

Semilunar valves. Because of their shape.

What is the vasa vasorum?

Series of blood vessels that supply the wall of large arteries

Epicardium is composed of what?

Serous membrane of connective tissue, includes capillaries and nerve fibers

What is the visceral pericardium?

Serous membrane that is attached to the surface of the heart

What is the parietal pericardium?

Serous membrane that lines fibrous layer

How does ventricular systole work? This cardiac period is first, second, or third?

Since blood from atria fills up ventricles, pressure increases fast causing AV valves to close (#1 LUB). Once the pressure is greater in ventricles, the semilunar valves open, blood rushes out into pulmonary trunk which allows ventricles to relax and the semilunar valves close (2# DUB) to prevent backflow. Second

What are capillaries?

Sites where exchange of substances between blood and body cells

What is a capillary? What do they do? What are they made of?

Smallest diameter blood vessels. Connect to arterioles and venules. Made of endothelium

What is the pericardial cavity?

Space between visceral and parietal pericardium

What is the difference between atrial/ventricular systole and atrial/ventricular diastole?

Systole is contraction. Diastole is relaxation

Where does the left ventricle pumps blood to?

The aorta

The opening between the atrium and the ventricle is?

The atrioventricular orifice

What divides the right and left atrium?

The inter-atrial septum

What divides the right and left ventricle?

The inter-ventricular septum

What are the two major pathways of blood vessels?

The pulmonary and the systematic circuits

Where does the right ventricle pump blood to?

The pulmonary trunk

What are the two upper chambers of the heart?

The right atrium and the left atrium

What are the two lower chambers of the heart?

The right ventricle and the right ventricle

What are chordae tendinae? What's their function?

They are fibrious strings, and prevent cusps of A-V valves from swinging back into atria.

What are the characteristics of an arteriole?

They are made of Edothelium (Tunica Intima), some smooth muscle nerve cells and connective tissue

What are the characteristics of an artery?

They are strong, elastic vessels, carry blood away from heart

veins

They carry blood from lungs to left atrium

What is the purpose of the Purkinje fibers? Where are they located?

To carry impulses to distant regions of the ventricular myocardium. Located in the bottom portion of the inter-ventricular septum, papillary muscles and in ventricular walls.

What is the function of the serious fluid in pericadrial cavity?

To reduce friction

True or false, endocardium is the inner lining of the blood vessels attached to the heart?

True

True or false...pressure in the ventricles is low during ventricular diastole

True

What happens when atria contract?

Ventricles relax

What happens during ventricular diastole? What happens to the pressure?

Ventricular pressure increases causing the pulmonary valves to open. As blood flows out of ventricles, pressure decreases.

When do the semilunar valves close?

When pressure in ventricles is lower than the pressure in the aorta and pulmonary trunk

How does early diastole work? This cardiac period is first, second, or third?

When the intraventricular pressure drops below the pressure of the atria, the AV are forced open which then allows blood to fill the ventricles again, completing the Cardiac Cycle. Third

Are the A-V valves open during diastole?

Yes

Does emotion play a role in heart rate? What does fear and anger release? What does grief do?

Yes Epinephrine - increases heart rate Stimulates CIC - decreases heart rate

Venules

continue from capillaries and merge to form veins

The heart is (location)

laterally by the lungs, behind the sternum, and in front of vertebral column

Where is the S-A (Sino-Atrial Node) located? What is it made out of? What is it called, and why? Where does the action go to?

located on the posterior wall of right atrium beneath epicardium, below opening of superior vena cava it is made out of specialized muscle tissue It is also referred as the pacemaker (self-exciting cells) because it generates the heart's rhythmic contractions The action potential spreads to ... a) muscle cells in both atria b) AV (atrio-ventricular) node

Vein

middle layer is very thin and poorly developed compared to an artery