Structure of the heart

Apex

The apex of the heart moves considerably with each heartbeat, and the point of maximal impulse (PMI) can be felt on the chest wall above the apex. The apex of the heart is likewise its tip, but it is formed by the left ventricle, so it is essentially the most inferior portion of the heart..

brachiocephalic artery

The brachiocephalic artery supplies blood to the tissues of the brain and the head. It is the first branch of the aortic arch and rises up to a point near the junction of the sternum (breast bone) and the right clavicle (collarbone).

Aorta

The aorta is the largest artery in the body The aorta extend down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta begins at the top of the left ventricle the heart's muscular pumping chamber. The heart pumps blood from the left ventricle into the aorta through the aortic valve. Three leaflets on the aortic valve open and close with each heartbeat to allow one-way flow of blood. The aorta distributes oxygenated blood to all parts of the body through the systemic circulation.

aortic valve

The aortic valve, or aortic semilunar valve, has three leaflets or cusps. It is located at the base of the aorta. It opens to allow blood to leave the left ventricle as it contracts. When the ventricular muscles relax, the valve closes to prevent blood from backing up into the ventricular chamber.

atrioventricular node

The atrioventricular node, or AV node is a part of the electrical conduction system of the heart that coordinates the top of the heart. It electrically connects the right atrium and right ventricle. The AV node lies at the lower back section of the interatrial septum near the opening of the coronary sinus, which conducts the normal electrical impulse from the atria to the ventricles.

chordae tendineae

The chordae tendineae are a group of tough, tendinous strands in the heart. They are commonly referred to as the "heart strings" since they resemble small pieces of string. Functionally, the chordae tendineae play a vital role in holding the atrioventricular valves in place while the heart is pumping blood.

inferior vena cava

The inferior vena cava is a vein. It carries deoxygenated blood from the lower half of the body to the right atrium of the heart. The inferior vena cava is an important vein that drains blood from all of the parts of the body below the diaphragm - including the feet, legs, reproductive, and lower-abdominal organs.

interventricular septum

The interventricular septum separates the left ventricle from the right ventricle. The interventricular septum is slanted backwards and to the right, and it also curves to the right, which completes the oval of the thick ventricle and encroaches upon the chamber of the right ventricle

left atrium

The left atrium is one of the four chambers of the heart, located on the left posterior side. Its primary roles are to act as a holding chamber for blood returning from the lungs and to act as a pump to transport blood to other areas of the heart. The walls of the left atrium are slightly thicker than the walls of the right atrium.

Bundle branches

The phrase bundle branches refers to the three branches of the bundle of His, a grouping of heart muscle cells which are responsible for transmitting the electrical impulses from the heart's AV node to the top of its fascicular branches; in turn, this transmits the electrical impulses to the heart's Purkinje fibers, which lead to the regular contraction of the cardiac muscles in the left and right ventricles.

pulmonary artery

The pulmonary artery carries blood from the right ventricle of the heart to the lungs for oxygenation. (The process of adding oxygen to something). The blood here passes through capillaries adjacent to alveoli and becomes oxygenated as part of the process of respiration

sinoatrial node

The sinoatrial node (SA node), also known as sinus node, is a group of cells located in the wall of the right atrium of the heart. These cells have the ability to spontaneously produce an electrical impulse that travels through the heart causing it to contract.

coronary arteries

Coronary arteries supply blood to the heart muscle.

pulmonary veins

Pulmonary veins are responsible for carrying oxygenated blood from the lungs back to the left atrium of the heart. The pulmonary veins are the veins that transfer oxygenated blood from the lungs to the heart.

Purkinje fibers

Purkinje fibers are also called subendocardial branches, or Purkyne tissues. These myocardial fibers can be found in the heart's inner ventricular walls. They conduct electrical impulses which permit the heart to contract in a coordinated way.

right atrium

Right atrium: The right upper chamber of the heart. The right atrium receives deoxygenated blood from the body through the superior vena cava and pumps it into the right ventricle which then sends it to the lungs to be oxygenated.

Iliac artery

The external iliac artery provides the main blood supply to the legs. It passes down along the brim of the pelvis and divides into two large branches - the inferior epigastric artery and a deep circumflex artery. These vessels supply blood to the muscles and skin in the lower abdominal wall.

Heart

The heart is divided into four chambers consisting of two atriums and two ventricles; the atrium receive blood, while the ventricles pump blood. The right atrium receives blood from the superior and inferior vena cavas and the coronary sinus; blood then moves to the right ventricle where it is pumped to the lungs.

interatrial septum

The interatrial septum is the wall of tissue that separates the right and left atrium of the heart.

superior vena cava

a large vein carrying deoxygenated blood into the heart. There are two in humans, the inferior vena cava (carrying blood from the lower body) Superior Vena Cava, a short trunk vein that drains deoxygenated blood from the head, neck, thorax, and arms.

Alveoli

small air spaces in the lungs where carbon dioxide leaves the blood and oxygen enters it rapidly.

Aorta arch

the aorta it curves above the heart between the ascending and descending aorta. All of the blood delivered from the heart to the systemic tissues of the body passes through the aorta, making it the largest artery in the human body. As the aorta extends from the heart, it begins as the ascending aorta before turning 180 degrees towards the body's left side in the aortic arch.