Cardiac Anatomy and Physiology Review

This set of vocabulary flashcards covers cardiac anatomy, the cardiac conduction system, and electrocardiogram (ECG) components based on lecture questions and matching pairs.

Electrocardiogram (ECG)

A recording of electrical changes occurring in the myocardium during the cardiac cycle.

Aorta

The large artery that distributes blood to body organs (systemic circuit) except the lungs and possesses a thicker wall to withstand high pressure from the left ventricle.

Pulmonary trunk

The structure that gives rise to the left and right pulmonary arteries and has a thinner wall related to the lower pressure of blood leaving the right ventricle.

Polarized

The state of cardiac muscle fibers between cardiac cycles when no electrical changes are detectable.

AV node

A structure of the conduction system located in the inferior portion of the interatrial septum.

SA node

The component of the conduction system that normally serves as the pacemaker of the heart.

Tachycardia

A term describing a rapid heartbeat.

Bradycardia

A term describing a slow heartbeat.

T wave

The portion of an ECG that corresponds to the repolarization of the muscle fibers of the ventricles.

Chordae tendineae

Fibrous cords originating from papillary muscles that prevent the cusps of the AV valves from swinging into the atria.

Papillary muscle

The structure from which chordae tendineae originate to support the heart valves.

Pericardial sac

The membranes that surround and enclose the heart.

Tricuspid valve

The valve that prevents blood movement from the right ventricle to the right atrium.

Mitral valve

The valve that prevents blood movement from the left ventricle to the left atrium.

Coronary sinus

The vessel that drains blood from the myocardium into the right atrium.

Endocardium

The inner lining of the heart chambers.

Myocardium

The heart layer largely composed of cardiac muscle tissue.

Pericardial cavity

The space containing serous fluid to reduce friction during heartbeats.

Cardiac vein

The vessel that drains blood from the myocardial capillaries.

Coronary artery

The vessel that supplies blood directly to the heart muscle.

Diastole

The period during the cardiac cycle when a heart chamber is relaxing.

Systole

The period during the cardiac cycle when a heart chamber is contracting.

Cardiac conduction system

Fibers composed of specialized cardiac muscle tissue that coordinate the heartbeat.

P wave

The portion of an ECG that corresponds to the depolarization of the muscle fibers of the atria.

QRS complex

The portion of an ECG corresponding to the depolarization of the muscle fibers of the ventricles, which also obscures atrial repolarization.

Apex

The inferior, rounded end of the heart.

Purkinje fibers

Fibers that carry cardiac impulses from the interventricular septum into the myocardium.

Atria

The two superior chambers of the heart; approximately $70\,\%$ of blood passes from these into the ventricles before their walls contract.

Ventricles

The heart chambers that pump blood out; the right ventricle moves blood to the lungs, and the left ventricle moves blood to the rest of the body.

Murmur

The sound created when blood leaks back through an incompletely closed valve.

PQ (PR) interval

The interval indicating the time required for the atria to depolarize and the cardiac impulse to reach the AV node.

Right atrioventricular valve

A valve composed of three relatively large cusps that contain chordae tendineae.

Pulmonary valve

A valve made up of three small pocket-like cusps that lack chordae tendineae.