Heart and Cardiovascular System Anatomy

This set covers the anatomy, chambers, valves, and circulatory pathways of the heart and cardiovascular system as described in the lecture notes.

Cardiovascular system

The system comprising the heart, arteries, veins, and capillaries.

Pulmonary circuit

The division on the right side of the heart that carries oxygen-poor, $CO_2$-rich blood to the lungs for gas exchange.

Systemic circuit

The division on the left side of the heart that supplies oxygen-rich, $CO_2$-poor blood to all organs of the body.

Mediastinum

The location of the heart, situated between the lungs.

Base (of the heart)

The broad superior portion of the heart, measuring $3.5\,\text{in.}$ wide.

Apex (of the heart)

The inferior end of the heart that tilts to the left and tapers to a point; it is $5\,\text{in.}$ from the base.

Heart Dimensions

Measures $3.5\,\text{in.}$ wide at the base, $5\,\text{in.}$ from base to apex, and $2.5\,\text{in.}$ from anterior to posterior; weighs $10\,\text{oz}$.

Pericardium

A structure that allows the heart to beat without friction, provides room to expand, and resists excessive expansion.

Parietal pericardium

The outer layer consisting of a tough, fibrous layer (fibrous pericardium) and an inner, thin, smooth, moist serous layer (serous pericardium).

Pericardial cavity

The space between the parietal and visceral pericardium filled with pericardial fluid.

Visceral pericardium

Also known as the epicardium; the thin, smooth, moist serous layer that covers the heart surface.

Myocardium

The thick muscular layer of the heart wall containing a fibrous skeleton of collagenous and elastic fibers for structural support and coordination.

Endocardium

The smooth inner lining of the heart wall.

Atria

The two superior "Receiving chambers" that receive blood returning to the heart.

Auricles

Ear-like flaps on the atria that add to the atrial surface area.

Ventricles

The two inferior "Pumping chambers" that pump blood into the arteries.

Septum

The structure that divides the right and left sides of the heart.

Tricuspid valve

The right atrioventricular (AV) valve, which consists of 3 cusps.

Mitral valve

Also known as the bicuspid valve; the left atrioventricular (AV) valve, which consists of 2 cusps.

Chordae tendineae

Cords that connect atrioventricular (AV) valves to the papillary muscles on the floor of the ventricles.

Semilunar (SL) valves

Valves that control blood flow into the great arteries, specifically the pulmonary and aortic valves.

Fossa ovalis

A feature located in the internal anatomy of the right atrium.

Trabeculae carneae

Internal ridges of muscle found in the heart ventricles.

Arteries

Strong, elastic vessels made of smooth muscle tissue that carry blood away from the heart under high pressure.

Veins

Vessels that carry blood to the heart under low pressure, containing semilunar valves and serving as a blood reservoir.

Capillaries

Microscopic blood vessels that allow for oxygen and carbon dioxide gas exchange.

Venules

Microscopic blood vessels that collect blood from capillaries and join together to form veins.

Arterioles

The thinnest divisions of arteries that lead into capillaries.

Coronary circulation

The blood supply route specifically for the heart tissue.

Hepatic portal system

A specialized part of systemic circulation where veins from the spleen and digestive organs are sent through the liver.

Circle of Willis

The blood vessel arrangement responsible for nourishing the brain tissue.

Blood Vessel Layers

The three layers of a vessel: Tunica interna (endothelium and basement membrane), Tunica media, and Tunica externa.