Cardiovascular Physiology and Heart Anatomy

Vocabulary flashcards covering heart structure, cardiac circulation, clinical pathologies, and the cardiac conduction system.

Systemic Circuit

The circulatory circuit that operates at a higher pressure than the pulmonary circuit because it must pump blood to the entire rest of the body.

Pulmonary Edema

A physiological complication caused by an abnormal increase in pressure within the pulmonary circuit.

Xiphoid Process

The sharp, flat inferior portion of the sternum that must be avoided during CPR compression to prevent bone fracture and internal tissue injury.

Pericardium

A serous membrane enclosing the heart consisting of an inner visceral layer and an outer parietal layer separated by a fluid-filled space that eliminates friction.

Cardiac Tamponade

A severe condition resulting from pericarditis where thickened membranes or inflammatory fluid restrict heart movement and prevent proper contraction.

Desmosomes

Cellular junctions within intercalated discs composed of cytoskeleton extensions that prevent cardiomyocytes from pulling apart during contraction.

Gap Junctions

Intercellular channels in intercalated discs that allow electrical impulses to propagate directly between cardiomyocytes.

Fibrous Skeleton

The connective tissue structure that provides physical shape to the heart and functions as an electrical non-conductor.

Spiral Orientation

The dynamic arrangement of cardiac muscle fibers required for the ventricles to efficiently wring and pump blood.

Tetralogy of Fallot

A congenital heart defect involving four specific structural deformities, causing severe cyanosis in infants referred to as blue or purple babies.

Stenosis

The pathological narrowing of a heart valve orifice, such as the semilunar aortic valve, which obstructs blood outflow and increases ventricular pressure.

Rheumatic Fever

An autoimmune reaction triggered by Streptococcus hemolyticus Type A infection where immune complexes cause permanent damage to heart valves.

Angina Pectoris

Transient chest pressure or pain caused by temporary coronary ischemia, typical in window shoppers, which subsides after $5$ to $10$ minutes (maximum $15$ minutes) of rest.

Anterior Interventricular Branch

A major branch of the left coronary artery (also called the LAD) supplying both ventricles and the anterior $\frac{2}{3}$ of the interventricular septum.

Myoglobin

An iron- and oxygen-binding protein found specifically within muscle tissue, including cardiomyocytes, that stores oxygen.

Sinoatrial Node

The natural pacemaker of the heart located in the wall of the right atrium that sets the normal sinus rhythm.

Nodal Rhythm

A slower heart rhythm established by the atrioventricular node when the sinoatrial node fails to fire.

Subendocardial Network

The conduction fibers distributed throughout the ventricular myocardium, formerly referred to as Purkinje fibers.

Vagus Nerve

Cranial nerve $10$, which provides parasympathetic innervation to the cardiac plexus and can reduce the heartbeat down to approximately $30\,\text{bpm}$.

Positive Chronotropic Factors

Factors, hormones, or neural inputs that increase the frequency or rhythm of the heart rate.