Anatomy and Physiology: The Heart and Circulatory Dynamics

Comprehensive vocabulary flashcards detailing cardiac anatomy, heart wall layers, internal and external structures, heart valves, and the pathway of blood circulation.

Base of the Heart

The broad, superior aspect of the heart where the major blood vessels emerge.

Apex of the Heart

The pointed inferior tip of the heart that points toward the left side of the body and rests on the diaphragm.

Mediastinum

The thoracic cavity space between the sternum and left nipple (ribs two through five) where the heart is located.

Fibrous Pericardium

The superficial, tough connective tissue layer of the pericardial sac that anchors and protects the heart while preventing it from overstretching.

Parietal Pericardium

The outer serous membrane layer that lines the inner surface of the fibrous pericardium.

Visceral Pericardium (Epicardium)

The innermost serous membrane layer positioned directly against the outer surface of the heart, which also accumulates protective adipose tissue.

Pericardial Fluid

Fluid found in the pericardial cavity between the parietal and visceral layers that reduces friction as the heart beats.

Pericarditis

Inflammation of the pericardial membranes, often characterized by excess fluid accumulation that can compress the heart and impede its beating.

Myocardium

The thick middle layer of the heart wall composed of cardiac muscle; it is unique to the heart and not found in blood vessels.

Endocardium

The inner simple squamous epithelial lining of the heart chambers and valves, continuous with the endothelium of the blood vessels.

Endothelium

The simple squamous epithelial layer lining the lumen of blood vessels, structurally identical to the endocardium.

Atria

The thin-walled upper receiving chambers of the heart through which blood passes before entering the ventricles.

Ventricles

The muscular lower discharging chambers of the heart that actively pump blood into systemic or pulmonary circulation.

Auricle

A small, ruffled, pouch-like external flap located on the anterior surface of each atrium.

Pectinate Muscles

Muscular ridges located inside the atria that resemble bare, branching tree limbs.

Superior Vena Cava (SVC)

A large systemic vein that delivers deoxygenated blood from regions superior to the diaphragm into the right atrium.

Inferior Vena Cava (IVC)

A large systemic vein that delivers deoxygenated blood from regions inferior to the diaphragm into the right atrium.

Coronary Sinus

A venous vessel situated on the posterior heart that empties deoxygenated blood from the coronary circulation directly into the right atrium.

Pulmonary Veins

Four vessels (two from the left lung, two from the right) that return oxygenated blood from the lungs into the left atrium.

Interatrial Septum

The internal muscular partition separating the right atrium from the left atrium.

Foramen Ovale

An opening in the interatrial septum of the fetal heart that normally seals shut by about three months of age.

Fossa Ovalis

The shallow depression or white mark on the interatrial septum in the adult heart representing the closed remnant of the foramen ovale.

Trabeculae Carneae

Irregular muscular ridges and bridges lining the inner walls of the ventricles.

Papillary Muscles

Cone-shaped muscles projecting from the ventricular walls that attach to and anchor the chordae tendineae.

Chordae Tendineae

Tendon-like fibrous cords, often called heart strings, that connect papillary muscles to atrioventricular valve cusps to prevent them from inverting during ventricular contraction.

Tricuspid Valve

The right atrioventricular valve having three cusps, which controls one-way blood flow from the right atrium into the right ventricle.

Bicuspid (Mitral) Valve

The left atrioventricular valve having two cusps, which prevents backflow from the left ventricle into the left atrium.

Semilunar Valves

Pocket-like, crescent-shaped valves (aortic and pulmonary) that open and close in response to ventricular pressure changes.

Pulmonary Semilunar Valve

The valve located at the base of the pulmonary trunk that prevents deoxygenated blood from backflowing into the right ventricle.

Aortic Semilunar Valve

The valve located between the left ventricle and the aorta that prevents backflow of blood into the left ventricle.

Mitral Valve Prolapse

A clinical condition where the cusps of the bicuspid valve flutter or bulge backward into the left atrium, potentially causing an audible murmur.

Regurgitation (Regurge)

The backward leaking or flow of blood through a heart valve that fails to seal completely.

Pulmonary Trunk

The large artery exiting the right ventricle that routes deoxygenated blood toward the lungs.

Bifurcate

The anatomical splitting or dividing of a structure into two branches, such as the pulmonary trunk splitting into the right and left pulmonary arteries.

VAVA Mnemonic

A memory aid representing the sequential flow of blood through heart structures: Veins to Atria, Ventricles to Arteries.