Structure of the Heart

Study Notes

The heart is a muscular, hollow organ that pumps blood throughout the body.
It is located in the thoracic cavity, between the lungs, and is protected by the rib cage.

Epicardium: The outermost layer, a thin layer of connective tissue that covers the heart.
Myocardium: The middle layer, a thick layer of cardiac muscle that contracts to pump blood.
Endocardium: The innermost layer, a thin layer of epithelial tissue that lines the heart chambers and valves.

Right Atrium: The upper right chamber that receives oxygen-depleted blood from the body.
Right Ventricle: The lower right chamber that pumps oxygen-depleted blood to the lungs.
Left Atrium: The upper left chamber that receives oxygen-rich blood from the lungs.
Left Ventricle: The lower left chamber that pumps oxygen-rich blood to the rest of the body.

Tricuspid Valve: Between the right atrium and ventricle, allows blood to flow from the atrium to the ventricle while preventing backflow.
Pulmonary Valve: Between the right ventricle and pulmonary artery, allows blood to flow from the ventricle to the lungs while preventing backflow.
Mitral Valve: Between the left atrium and ventricle, allows blood to flow from the atrium to the ventricle while preventing backflow.
Aortic Valve: Between the left ventricle and aorta, allows blood to flow from the ventricle to the rest of the body while preventing backflow.

Oxygen-depleted blood returns to the right atrium through the superior and inferior vena cavae.
Blood flows from the right atrium to the right ventricle through the tricuspid valve.
The right ventricle pumps blood to the lungs through the pulmonary valve.
Oxygen-rich blood returns to the left atrium through the pulmonary veins.
Blood flows from the left atrium to the left ventricle through the mitral valve.
The left ventricle pumps blood to the rest of the body through the aortic valve.

The heart receives its own blood supply through the coronary arteries, which arise from the aorta.
The coronary arteries branch into smaller arteries that supply blood to the myocardium.

The heart is a muscular, hollow organ located in the thoracic cavity between the lungs, protected by the rib cage.

The heart has three layers: epicardium, myocardium, and endocardium.
Epicardium is the outermost layer, a thin layer of connective tissue.
Myocardium is the middle layer, a thick layer of cardiac muscle that contracts to pump blood.
Endocardium is the innermost layer, a thin layer of epithelial tissue lining the heart chambers and valves.

The heart has four chambers: right atrium, right ventricle, left atrium, and left ventricle.
Right atrium receives oxygen-depleted blood from the body.
Right ventricle pumps oxygen-depleted blood to the lungs.
Left atrium receives oxygen-rich blood from the lungs.
Left ventricle pumps oxygen-rich blood to the rest of the body.

The heart has four valves: tricuspid, pulmonary, mitral, and aortic valves.
Tricuspid valve is between the right atrium and ventricle, preventing backflow.
Pulmonary valve is between the right ventricle and pulmonary artery, preventing backflow.
Mitral valve is between the left atrium and ventricle, preventing backflow.
Aortic valve is between the left ventricle and aorta, preventing backflow.

Oxygen-depleted blood returns to the right atrium through the superior and inferior vena cavae.
Blood flows from the right atrium to the right ventricle through the tricuspid valve.
The right ventricle pumps blood to the lungs through the pulmonary valve.
Oxygen-rich blood returns to the left atrium through the pulmonary veins.
Blood flows from the left atrium to the left ventricle through the mitral valve.
The left ventricle pumps blood to the rest of the body through the aortic valve.

The heart receives its own blood supply through the coronary arteries, which arise from the aorta.
The coronary arteries branch into smaller arteries that supply blood to the myocardium.