The Cardiovascular System: The Heart

In the systemic circuit, what delivers oxygenated blood to the systemic capillaries (the smallest blood vessels)?

arteries

pericardial cavity

filled with pericardial fluid (serous fluid)

what does the cardiovascular system consist of?

Heart, blood vessels, and blood

Apply: How would these effects differ from those of left-sided heart failure (failure of the left ventricle to pump adequately?

In left sided heart failure, oxygenated blood is not delivered to tissues adequately, so cells potentially won't receive enough oxygen and nutrients.

The left ventricle pumps blood into the .... and after this emerges from the left ventricle, 2 branches arise, the .... and ....

ascending aorta, left coronary artery, right coronary artery

Coronary circulation

because the myocardium is too thick for oxygen and nutrients to diffuse from inside the chambers to all of the organs cells, the heart is supplied by a set of blood vessels (coronary circulation)

another function of the heart is to maintain....

blood pressure this means to maintain the homeostasis of the pressure that blood exerts on the blood vessels (blood pressure) the rate and force of the heart's contraction are major factors that influence blood pressure and blood flow to organs

Cardiac tamponade

compression of the heart due to fluid accumulation within the pericardium

Layer of the heart wall: Epicardium

contains collagen bundles

a buildup of plaques in coronary arteries results in...

coronary artery disease (CAD) -decreases blood flow to the myocardium which results in inadequate oxygen of the myocardium- myocardial ischemia) - can cause heart pain (angina)

mitral valve prolapse (MVP)

occurs from mitral (bicuspid) or aortic valve -part of valve detaches from chordae tendineae allows backflow -heart murmurs occur because of valvular problems and the backflow that comes from that

coronary arteries deliver ... blood to the coronary capillary beds, where gas and nutrient exchange takes place within the ... Then the blood drains from the capillaries into a series of .... (middle, and great cardiac vein, and coronary sinus)

oxygenated, myocardium coronary veins

what are the two Right coronary arteries?

posterior interventricular artery, and the marginal branch

symptoms of myocardial ischemia

pressure, pain, shortness of breath, discomfort, lightheadedness

Valvular disorders: Rheumatic fever

prevents valve from working, backflow can occur affects mitral valve or semilunar aortic valve - triggered by a strep infection - it is an autoimmune disorder -affects CT found in valves and your joints (inflammation and reduced blood flow) - inflammation and reduced blood flow

the right side of the heart is sometimes called the ... because it pumps blood into a series of blood vessels leading to/within the lungs called the .... The pulmonary arteries of this circuit deliver oxygen- .... and carbon dioxide rich (....) blood to the lungs

pulmonary pump, pulmonary circuit poor, deoxygenated

myocardial ischemia (angina pectoris)

reduced oxygen delivery to myocardium especially with an increased workload (exercise- getting heart rate to work faster)

function of pericardial fluid

reduces friction during muscle contraction

the left side of the heart pumps blood to the...

rest of the body (this is why it is called a high pressure circuit)

what two circuits does it pump blood between?

systemic and pulmonary circulation

the left side of the heart is called the... and receives .... blood from the pulmonary veins and pumps it into the blood vessels that serve the rest of the body

systemic pump, oxygenated

serous pericardium function and what it looks like

thin, inner serous membrane that produces serous membrane prevents friction during muscle contraction

Function of heart valves: semilunar valves

Aortic and Pulmonary Valve- Prevent backflow of blood

fibrous pericardium composed of which helps with?

collagen bundles - make it tough and enable it to anchor the heart to structures (diaphragm, great vessels) -give the heart low distensibility (doesn't change shape or size when stretching forces are applied). this helps prevent chambers from overfilling

how much blood does the heart pump in one minute (in Liters)? how many times its weight does it pump blood in one minute?

- 5 L - 30 times

steps of the systemic circuit

1. Oxygenated blood is pumped to the body by the left side of the heart 2. gas exchange occurs between tissues and blood in the systemic capillaries. * oxygen diffuses from the blood into the tissues and CO2 diffuses from the tissues into the blood. Blood also delivers nutrients, picks up wastes to be excreted, and distributes hormones to their target cells throughout the body.

Left coronary artery: 1. anterior interventricular artery 2. circumflex artery

1. gives off branches that supply the interventricular septum 2. supplies the left atrium and parts of the left ventricle

Coverings of the heart: Pericardium

A sac with two components: fibrous pericardium and serous pericardium

the heart also acts as an endocrine organ and produces this organ

ANP (Atrial Natriuretic Peptide) helps control blood pressure by decreasing it helps you secrete sodium which helps you secrete other fluids

The heart consists of four hollow chambers...

Atria: right and left atria- both of these receive blood from veins (blood vessels that bring blood TO the heart). Blood drains from the atria to the ventricles Ventricles: right and left ventricles- pump blood into blood vessels called arteries (carry blood away from the heart)

Apply: How might coronary artery anastomoses help a patient with coronary artery disease?

Coronary artery anastomoses provide alternate routes of blood flow when the flow through a vessel is blocked

where is the heart located?

It is situated slightly to the left side in the thoracic cavity posterior to the sternum in the mediastinum, where it rests on the diaphragm. It is found in the pericardial cavity within the mediastinum

what is the procedure called that takes a syringe and removes fluid from the heart

Pericardiocentesis

Apply: Predict the potential effects of right-sided heart failure (failure of the right ventricle to pump adequately)

The right side of the heart pumps deoxygenated blood into the pulmonary circuit. Failure of the right ventricle to pump adequately would reduce the oxygenation of the blood that normally occurs in the lungs.

Function of heart valves: Atrioventricular valves

Tricuspid and Bicuspid (Mitral) valves. Tricuspid: prevents backflow of blood from right ventricle to right atria. Bicuspid- prevents backflow from left ventricle to left atria

pericarditis

caused by a bacteria infection two forms: acute and chronic acute- sudden, onset (pain). there is a decrease in the production of pericardial fluid chronic- starts out as acute, but when it is chronic, it is not necessarily associated with pain. It actually ends up oversecreting and more fluid is given off a decrease in pericardial (serous fluid)= an increase in friction

risk factors of CAD (9)

high cholesterol high blood pressure smoking obesity diabetes stress genetic presdisposition age gender (women are better off)

treatments for myocardial ischemia

limit strenuous activities stop smoking decrease lipid consumption attend to any associated problems (diabetes, high blood pressure, etc.)

Two layers of serous pericardium

parietal layer and visceral layer (epicardium)

stenosis

rheumatic fever can lead to this - thickening/hardening of the valve 1. mitral valve 2. aortic valve * blood will back into the previous system into the pulmonary circulation * if blood backs up into the pulmonary capillaries it can lead to pulmonary edema

atherosclerotic plaques

these form due to damage to the tunica interna (made of endothelium which has a basement membrane of collagen fibers)

Layer of the heart wall: Myocardium

tissue: cardiac muscle tissue (contains cardiac muscle cells- myocytes) and fibrous skeleton (composed of dense irregular collagenous CT) function: -fibrous skeleton gives cardiac muscle cells something to pull when they contract - acts as an insulator for the heart's electrical activity

the heart has many functions: what is its main function?

to pump blood

myocardial infarction -aka -what causes one?

- heart attack -when plaques in the coronary arteries rupture and a clot forms that obstructs blood flow to the myocardium which causes myocardial death cardiac muscle cells generally do not undergo mitosis so after a heart attack, the dead cells are replaced with fibrous, noncontractile scar tissue, death of part of myocardium increase workload of remaining heart muscle

parietal layer

-fused to inner surface of fibrous pericardium. The parietal layer encases the heart like a sac but when it reaches the great vessels, it folds under itself and creates the visceral layer tissue: collagen bundles

The pulmonary circuit steps (3)

1. Deoxygenated blood is pumped to the lungs by the right side of the heart 2. Gas exchange occurs between air in the alveoli (tiny air sacs in the lung) and blood in the pulmonary capillaries * during gas exchange oxygen diffuses from the air in the alveoli into the blood in the pulmonary capillaries, and CO2 diffuses from the blood in the pulmonary capillaries to the air in the alveoli, to be expired 3. Oxygenated blood is then returned to the left side of the heart by the veins

apply: Heart tissue dies during a myocardial infarction, and a person's survival and recovery depend on the extent of cell death and the chamber(s) involved. In which chamber would loss of function be most damaging to survival? explain your response.

death of cells in the left ventricle leads to the worst prognosis because it must pump blood to the entire systemic circuit. If the left ventricle fails, none of the body's cells are supplied with adequate oxygenated blood. The right ventricle does not have to contract as strongly to pump blood through the lower- resistance pulmonary circuit.

Apply: What might happen if the papillary muscles and/or chordae tendineae stopped functioning? would this affect the atrioventricular valves, the semilunar valves, or both? explain the potential consequences of this problem.

dysfunction of the papillary muscles and/or chordae tendineae would affect only the atrioventricular valves, as these muscles and cords do not attach to the semilunar valves. Such dysfunction could allow the AV valves to evert, letting blood leak back into the atria from the ventricles

Layer of the heart wall: endocardium

lines the lumen of the heart tissue: endothelium (special type of simple squamous epithelium) and several layers of CT with collagen and elastic fibers function: forms a blood-heart barrier (helps regulate concentration of electrolytes and other chemicals in the ECF of the myocardium) - prevents blood flow restrictions -covers our valves

possible results of CAD on the heart

low oxygen delivery to the tissues (myocardium)

the right side of the heart pumps blood to the ...

lungs (low pressure circuit)