Heart Anatomy Quiz

Pericardium

Pericardium

double-walled sac that covers the heart

Fibrous

protects the heart, anchors to surrounding tissues (e.g. diaphragm)

Serous

touches the heart itself and lines the mediastinum

Parietal

lines internal surface of the fibrous pericardium

Visceral

part of heart wall (covers myocardium); same as the epicardium

Endocardium

layer of squamous endothelium that lines the inside surface of the heart; very slick and continuous with tunica media in blood vessels; slick so that blood just slides through the heart

Myocardium

the muscle tissue of the heart, interlace in a spiral pattern around the heart; heart fibers go in a spiral so that it can narrow; interspersed with connective tissue (collagen) that acts as an insulator to e-charge, limiting action potential to specific pathways

Right Atrium

receives blood from the superior vena cava, inferior vena cava, and coronary sinus (collects blood from cardiac circulation); contains deoxygenated blood and has the tricuspid valve attached to it

Left Atrium

receives oxygenated blood from the lungs via the pulmonary veins, send to left ventricle

Right Ventricle

receives blood from right atrium and pumps it to lungs via the pulmonary artery (left and right branches)

Left Ventricle

receives blood from left atrium, pumps blood out to body cells via the aorta; most heavily muscles of heart chambers because it has to pump blood to the whole body

Semilunar valves

located between ventricles and arteries

Aortic

prevents blood flow back into left ventricle after contraction

Pulmonary

prevents blood flow back into right ventricle after contraction

Atrioventricular Valves

located between atria and ventricles

Tricuspid Valve

right AV valve; composed of three flaps of endocardium

Bicuspid (Mitral) Valve

composed of two flaps of endocardium

Interventricular Septum

the triangular wall of cardiac tissue that separates the left and right ventricles; a hole in the heart can result in mixing of high and low O2 blood

Vein

sends blood to the heart (pulmonary veins carry oxygenated blood)

Artery

sends blood to the rest of the body (pulmonary artery is the only artery to carry deoxygenated blood)

Cardiac Output

the amount of blood moved by the heart in one minute in each ventricle

End systolic Volume

the leftovers of blood after the contraction in the heart

End diastolic volume

the maximum that the ventricle can fill; total max amt of blood

Stroke Volume

amount of blood pumped out by one ventricle during each contraction (~70 ml)

Describe the pathway of blood through the heart starting in the right atrium

Coronary sinus (collects blood from cardiac circulation), superior and inferior vena cava collect blood from the body; right ventricle (receives blood from right atrium and pumps it to lungs via pulmonary artery; left atrium (receives oxygenated blood from lungs via pulmonary veins), left ventricle (pumps blood out to body cells via aorta; most heavily muscled because it has to pump blood to all parts of the body)

What is the purpose of the interventricular septum? What happens if this is compromised (e.g. hole-in-the-heart)

The interventricular septum separates the right and left ventricles. If it’s compromised, high and low oxygenated blood is mixed.

Describe the events leading to a myocardial infarction (heart attack). What is the end result of an MI

Coronary circulation can get blocked by damage or fatty deposits (plaque). The part of the muscle not getting any blood will eventually die, reducing the heart’s ability to pump blood depending on where the blockage is located.

Describe the forces that allow each of the heart valves to open and close

For example – the aortic valve closes when the pressure in the aorta is greater than that of the left ventricle. When the pressure in the left ventricle increases (over the aortic pressure) during contraction (systole), the aortic valve opens to let blood out of the heart. The papillary muscles and chordae tendineae adjust the tension of the valves which allows for more or less blood to come through.

What prevents the heart valves from prolapsing in a normal heart? What is it called if the valves DO prolapse

The chordae tendineae and papillary muscles by making sure there’s tension on the valves to prevent blood from backflowing. Incompetent valves

Autorhythmic Cells

sets the electrical impulse the heart reacts to when it beats; creates the EKG record

Coronary circulation

critical in supplying myocardium with O2, food, and in removing wastes; coronary arteries (arise from base of aorta and encircle the heart in the coronary sulcus), arteries (deliver blood to myocardium), veins (move deoxygenated blood back into circulation)

3 layers of blood vessels

tunica intima, tunica media, tunica externa

Tunica intima

innermost layer, directly in contact with flowing blood (continuous with endocardium)

Tunica media

mid-layer, made of smooth muscle and elastin, controls vessel diameter and blood pressure

Tunica externa

outermost layer, made of connective tissue but innervated and connected to lymph vessels

Vasa vasorum

small network capillaries that nourish the tissues in the outermost parts of larger blood vessels

Systole

contraction period

Diastole

relaxation period

Cardiac tamponade

the fluid sac around your heart fills with blood or other fluid, putting pressure on your heart

Autorhythmic centers

initiate their own contraction of the heart