cardiovascular system

Cardiovascular system

An organ system that circulates blood to transport oxygen nutrients hormones carbon dioxide and blood cells throughout the body.

Circulatory system

Another name for the cardiovascular or vascular system.

Vascular system

The network of the heart and blood vessels that circulates blood.

Arteries

Muscular-walled blood vessels that carry oxygenated blood away from the heart.

Veins

Thin-walled blood vessels that usually carry oxygen-depleted blood back toward the heart.

Capillaries

The smallest blood vessels where oxygen nutrients and wastes are exchanged between blood and tissues.

Vena cava

A large vein that carries deoxygenated blood into the heart.

Superior vena cava

The vein that carries deoxygenated blood from the head arms and upper body to the heart.

Inferior vena cava

The vein that carries deoxygenated blood from the lower body to the heart.

Pulmonary artery

Carries deoxygenated blood from the right ventricle to the lungs.

Pulmonary veins

Carry oxygenated blood from the lungs to the left atrium.

Aorta

The largest artery in the body carrying oxygenated blood from the left ventricle to the body.

Ascending aorta

The first portion of the aorta leaving the heart.

Aortic arch

The curved portion of the aorta that gives rise to major arteries supplying the head and arms.

Descending aorta

The section of the aorta that travels downward through the chest and abdomen.

Thoracic aorta

The portion of the descending aorta located in the chest.

Abdominal aorta

The portion of the descending aorta located in the abdomen.

Carotid arteries

Arteries that supply oxygenated blood to the head and neck.

Common carotid artery

The artery that divides into the internal and external carotid arteries.

Internal carotid artery

Supplies oxygenated blood to the brain.

External carotid artery

Supplies oxygenated blood to the face scalp and neck.

Arterioles

Small branches of arteries that regulate blood flow into capillaries.

Venules

Small branches of veins that receive blood from capillaries.

Carbon dioxide (CO2)

A waste product of cellular metabolism exchanged for oxygen in the lungs.

Microcirculation

The circulation of blood through capillaries arterioles and venules.

Endothelium

A single layer of cells lining blood vessels.

Heart

A muscular organ that pumps blood throughout the body.

Atria

The two upper receiving chambers of the heart.

Atrium

A single upper chamber of the heart.

Ventricles

The two lower pumping chambers of the heart.

Right atrium

Receives deoxygenated blood from the body.

Right ventricle

Pumps deoxygenated blood to the lungs.

Left atrium

Receives oxygenated blood from the lungs.

Left ventricle

Pumps oxygenated blood to the body through the aorta.

Septum

The muscular wall separating the right and left sides of the heart.

Epicardium

The outer layer of the heart wall that contains the coronary arteries.

Myocardium

The thick muscular middle layer of the heart responsible for contraction.

Endocardium

The smooth inner lining of the heart and heart valves.

Pericardium

A double-walled sac surrounding the heart.

Parietal pericardium

The outer layer of the pericardial sac.

Visceral pericardium

The inner layer of the pericardial sac attached to the heart.

Cardiac valves

Structures that keep blood flowing in one direction through the heart.

Tricuspid valve

Valve between the right atrium and right ventricle.

Pulmonary valve

Valve between the right ventricle and pulmonary artery.

Mitral valve

Valve between the left atrium and left ventricle.

Bicuspid valve

Another name for the mitral valve.

Aortic valve

Valve between the left ventricle and the aorta.

Cardiac cycle

All events associated with one complete heartbeat.

Systole

The contraction phase of the heartbeat.

Diastole

The relaxation phase of the heartbeat.

Cardiac output

The amount of blood pumped by each ventricle per minute.

Heart sounds

The sounds produced by the closing of the heart valves.

Lub

The first normal heart sound caused by closure of the AV valves.

Dub

The second normal heart sound caused by closure of the semilunar valves.

Murmur

An abnormal whooshing or swishing heart sound caused by turbulent blood flow.

Conduction system

A specialized electrical pathway that controls the heartbeat.

Pacemaker

The heart's natural electrical system that initiates contractions.

Sinoatrial (SA) node

The heart's natural pacemaker that initiates each heartbeat.

Atrioventricular (AV) node

Receives impulses from the SA node and relays them to the ventricles.

Bundle of His

A conduction pathway carrying impulses from the AV node.

Bundle branches

Right and left pathways that carry electrical impulses through the ventricles.

Purkinje fibers

Specialized fibers that distribute electrical impulses throughout the ventricles.

Electrocardiogram (ECG/EKG)

A test that records the electrical activity of the heart.

P wave

Represents atrial depolarization.

QRS complex

Represents ventricular depolarization.

T wave

Represents ventricular repolarization.

Blood pressure

The force of blood pushing against artery walls.

Sphygmomanometer

An instrument used to measure blood pressure.

Systolic pressure

The highest blood pressure during ventricular contraction.

Diastolic pressure

The lowest blood pressure during ventricular relaxation.

Arrhythmia

An abnormal heart rhythm caused by problems with the heart's electrical system.

Digoxin

A medication used to strengthen heart contractions and treat certain arrhythmias.

Bradycardia

A heart rate slower than 60 beats per minute.

Heart block

A delay or interruption of electrical impulses between the atria and ventricles.

Cardiac pacemaker

A small implanted device that regulates abnormal heart rhythms.

Biventricular pacemaker

A pacemaker that synchronizes contractions of both ventricles in heart failure patients.

Flutter

A fast regular rhythm caused by rapid atrial contractions.

Fibrillation

Very rapid random ineffective contractions of the heart muscle.

Atrial fibrillation

An irregular and often rapid rhythm originating in the atria.

Ventricular fibrillation

A life-threatening rhythm in which the ventricles quiver instead of pumping blood.

Cardiac arrest

A sudden loss of heart function.

Defibrillation

Delivery of an electrical shock to restore a normal heart rhythm.

Coarctation of the aorta (CoA)

A congenital narrowing of the aorta.

Patent ductus arteriosus (PDA)

A congenital condition in which the duct between the aorta and pulmonary artery remains open.

Atrial septal defect (ASD)

A hole in the wall separating the atria.

Ventricular septal defect (VSD)

A hole in the wall separating the ventricles.

Tetralogy of Fallot

A congenital heart defect consisting of four structural abnormalities causing poor oxygenation.

Congestive heart failure (CHF)

A condition in which the heart cannot pump enough blood to meet the body's needs.

Ventricular assist device (VAD)

A mechanical pump that helps a weakened heart circulate blood.

Coronary artery disease (CAD)

Narrowing of the coronary arteries due to plaque buildup.

Atherosclerosis

The buildup of fatty plaque inside arteries.

Thrombotic occlusion

A blockage of an artery by a blood clot.

Ischemia

A decrease or loss of blood supply to tissue.

Necrosis

Death of body tissue.

Infarction

Death of tissue caused by loss of blood supply.

Acute coronary syndrome (ACS)

A group of conditions caused by reduced blood flow to the heart.

Unstable angina

Chest pain that occurs at rest or becomes more frequent.

Myocardial infarction (MI)

A heart attack caused by blockage of blood flow to heart muscle.