Anatomy and Physiology of the Heart

A set of practice vocabulary flashcards covering heart anatomy, layers, valves, the cardiac cycle, conduction system, and ECG components based on the lecture transcript.

Pulmonary circuit

The right-side pump of the heart that moves blood to the lungs and back.

Systemic circuit

The left-side pump of the heart that moves blood to the body and back.

Atria

The top chambers of the heart.

Ventricles

The bottom chambers of the heart.

Fibrous pericardium

The part of the pericardium that anchors the heart to the diaphragm and vessels.

Serous pericardium

The part of the pericardium that reduces friction, consisting of parietal and visceral layers with a pericardial cavity and serous fluid.

Pericardial Sac

A structure formed by the fibrous pericardium and the parietal pericardium.

Epicardium

The outermost layer of the heart wall, consisting of visceral pericardium, areolar connective tissue, and fat.

Myocardium

The middle layer of the heart consisting of cardiac muscle.

Endocardium

The innermost layer of the heart composed of simple squamous epithelium and areolar connective tissue.

Auricles

External ear-like structures on the heart atria.

Sulci

The plural form of sulcus; grooves on the external anatomy of the heart often containing fat and blood vessels.

Atrioventricular (AV) valves

The valves between the atria and ventricles, consisting of the tricuspid valve (right) and bicuspid/mitral valve (left).

Semilunar valves

The heart valves that include the pulmonary semilunar valve and the aortic semilunar valve.

Chordae tendineae

String-like structures that connect the papillary muscles to the cusps of the atrioventricular valves.

Papillary muscles

Muscles in the ventricles that contract to prevent valve flaps from everting into the atria.

Pectinate muscles

Muscle ridges located within the atria.

Trabeculae carneae

Muscle ridges located on the internal walls of the ventricles.

Interventricular septum

The wall that separates the right and left ventricles.

Systole

A phase of the cardiac cycle when a chamber empties.

Diastole

A phase of the cardiac cycle when a chamber relaxes and fills.

Lubb

The first heart sound, associated with ventricular contraction and the closing of the AV valves.

Dubb

The second heart sound, associated with early diastole and the closing of the semilunar valves.

Sinoatrial (SA) node

Known as the pacemaker, it initiates the contraction impulse in the heart.

Atrioventricular (AV) node

The site where there is a $100\text{-msec}$ delay in the impulse before it spreads to the ventricles.

Purkinje fibers

Fibers that distribute the electrical impulse throughout the ventricular myocardium to trigger contraction.

P wave

The part of an ECG showing the impulse spreading across the atria, triggering atrial contractions.

QRS complex

The part of an ECG showing the impulse spreading to the ventricles, triggering ventricular contractions.

T wave

The part of an ECG showing the ventricles returning to their resting state.

Coronary sinus

The vessel into which cardiac veins drain before entering the right atrium.