Anatomy of the Heart and Cardiac Conduction System

Flashcards covering heart anatomy, layers, valves, conduction system structures, unique cell characteristics, diagnostic procedures, devices, and risk factors.

Atria

Upper chambers of the heart.

Ventricles

Lower chambers of the heart.

Septum

Thick muscular wall that divides the heart into right and left sections.

Endocardium

The inner layer of the heart wall.

Myocardium

The middle muscular layer of the heart wall.

Epicardium

The outer layer of the heart wall, also known as the visceral pericardium.

Atrioventricular (AV) valves

Valves that, when closed, prevent the backflow of blood into the atrium.

Semilunar (SL) valves

Valves that allow blood to flow out of the heart and prevent backflow of blood into the ventricles.

Cardiac cycle

A complete heartbeat divided into diastole and systole phases.

Automaticity

The characteristic of cardiac electrical cells to initiate impulses with little to no conscious effort, attention, or awareness.

Excitability

The characteristic of cardiac electrical cells to respond to stimulation.

Conductivity

The characteristic of cardiac electrical cells where electrical signals travel to coordinate the heartbeat.

Sinoatrial (SA) node

A primary pacemaker structure within the conduction system of the heart.

Bundle of His

A structure in the cardiac conduction system also called the AV bundle.

Purkinje fibers

Conduction system fibers that spread electrical signals through the ventricles.

Conduction System Structures

The electrical system of the heart consisting of the SA node, AV node, Bundle of His, right and left bundle branches, and Purkinje fibers.

Risk Factors for Heart Disease

Conditions and behaviors including age, gender, genetics, race, smoking, high cholesterol, high blood pressure, uncontrolled diabetes, lack of exercise, obesity, stress, and alcohol.

Doppler ultrasounds

Diagnostic procedures that provide information on blood flow in the arms and legs, used to diagnose conditions such as arteriosclerosis, arterial occlusion, peripheral artery disease, aneurysms, arterial stenosis, and venous insufficiency.

Echocardiography

A sonographic test that uses sound waves to create pictures of heart structures.

Transthoracic echocardiogram (TTE)

The most common type of echocardiogram test undergone by patients.

Pacemakers

Devices that use low-energy electrical pulses to assist the heart, which can be temporary or permanent.

Implantable cardioverter defibrillator (ICD)

A device similar to a pacemaker that can also use high-energy pulses when a life-threatening arrhythmia occurs.

ECG Waveform and Segments

Electrical recording of the heart featuring the P wave, Q wave, R wave, S wave, T wave, P-Q segment, and S-T segment.