Overview of Heart Anatomy and Blood Circulation

Right atrium

Receives deoxygenated blood from the body via the superior and inferior vena cava.

Right ventricle

Pumps deoxygenated blood to the lungs through the pulmonary artery.

Left atrium

Receives oxygenated blood from the lungs via the pulmonary veins.

Left ventricle

Pumps oxygenated blood to the body through the aorta.

Tricuspid valve

Valve between the right atrium and right ventricle that prevents backflow.

Pulmonary valve

Valve between the right ventricle and pulmonary artery.

Mitral (bicuspid) valve

Valve between the left atrium and left ventricle.

Aortic valve

Valve between the left ventricle and aorta.

Aorta

Largest artery in the body; carries oxygenated blood from the heart to the body.

Pulmonary artery

Carries deoxygenated blood from the right ventricle to the lungs.

Pulmonary veins

Bring oxygenated blood from the lungs to the left atrium.

Superior vena cava

Brings deoxygenated blood from the upper body to the right atrium.

Inferior vena cava

Brings deoxygenated blood from the lower body to the right atrium.

Septum

Wall that separates the right and left sides of the heart.

Systole

The phase when the heart muscle contracts to pump blood.

Diastole

The phase when the heart muscle relaxes and the chambers fill with blood.

Lub sound

Caused by closure of the atrioventricular valves (tricuspid and mitral).

Dub sound

Caused by closure of the semilunar valves (aortic and pulmonary).

Red blood cells (RBCs)

Carry oxygen using hemoglobin; lack nuclei.

White blood cells (WBCs)

Defend the body against infection and disease.

Platelets

Help in blood clotting by forming a plug at wound sites.

Plasma

Liquid portion of blood; carries nutrients, hormones, and waste.

Hemoglobin

Protein in red blood cells that binds and transports oxygen.

Arteries

Carry blood away from the heart; thick muscular walls.

Veins

Carry blood toward the heart; have valves to prevent backflow.

Capillaries

Microscopic vessels for gas and nutrient exchange.

Foramen ovale

Opening between the right and left atria in the fetal heart to bypass lungs.

Ductus arteriosus

Connects pulmonary artery to the aorta in fetus to bypass lungs.

Umbilical vein

Carries oxygenated blood from the placenta to the fetus.

Umbilical arteries

Carry deoxygenated blood from the fetus to the placenta.

Hypertension

High blood pressure; increases risk of stroke and heart disease.

Atherosclerosis

Buildup of fatty plaques in arteries, narrowing them.

Heart failure

When the heart can't pump enough blood to meet the body's needs.

Myocardial infarction (heart attack)

Blockage of blood flow to the heart muscle.

Arrhythmia

Irregular heartbeat due to electrical signal problems in the heart.

Stroke

Occurs when blood flow to the brain is interrupted.

Anemia

Low red blood cell or hemoglobin count, leading to reduced oxygen delivery.