Cardiovascular System Lecture Notes

Comprehensive vocabulary flashcards covering the anatomy, physiology, and clinical conditions of the human cardiovascular system as described in Chapter 15 of Hole’s Human Anatomy & Physiology.

Cardiovascular System

A system consisting of the heart and blood vessels that transports respiratory gases, nutrients, and wastes through the body.

Pulmonary circuit

The pathway that carries oxygen-poor blood from the heart to the lungs and returns oxygen-rich blood to the heart.

Systemic circuit

The pathway that transports oxygen-rich blood and nutrients to body cells and removes wastes from cells.

Mediastinum

The region inside the thoracic cavity, behind the sternum and above the diaphragm, where the heart is located.

Epicardium

The thin outer layer of the heart wall that reduces friction; it is also known as the visceral pericardium.

Myocardium

The thick middle layer of the heart wall composed of cardiac muscle tissue used to pump blood.

Endocardium

The inner layer of the heart wall that forms the inner lining of all heart chambers.

Atria

The thin-walled upper chambers of the heart that receive blood returning to the heart.

Ventricles

The thick-walled lower chambers of the heart that pump blood into the arteries.

Tricuspid valve

A valve located at the right atrioventricular orifice that prevents blood from moving from the right ventricle into the right atrium during ventricular contraction.

Mitral valve

A valve located at the left atrioventricular orifice, also called the bicuspid valve, that prevents backflow into the left atrium during ventricular contraction.

Chordae tendineae

Fibrous strings that attach the cusps of the tricuspid and mitral valves to the papillary muscles in the heart wall.

Skeleton of the heart

Rings of dense connective tissue surrounding the heart valves and orifices that provide attachment for muscle fibers and prevent excess dilation.

Systole

The phase of the cardiac cycle representing the contraction of a heart chamber.

Diastole

The phase of the cardiac cycle representing the relaxation of a heart chamber.

Functional syncytium

A mass of merging cells that function as a unit, such as the atrial syncytium or ventricular syncytium in the heart.

SA node

The pacemaker of the heart; a specialized group of muscle cells that initiates rhythmic contractions.

AV node

A component of the conduction system that delays the cardiac impulse, allowing the atria to finish contracting before the ventricles contract.

Purkinje fibers

Large fibers that conduct cardiac impulses to the ventricular myocardium, causing them to contract in a twisting motion.

ECG (Electrocardiogram)

A recording of the electrical changes that occur in the myocardium during a cardiac cycle.

P wave

The deflection in an ECG representing atrial depolarization.

QRS complex

The set of waves in an ECG representing ventricular depolarization.

T wave

The deflection in an ECG representing ventricular repolarization.

Fibrillation

Uncoordinated, chaotic contraction of small areas of the myocardium.

Tachycardia

An abnormally fast heartbeat, defined as more than $100\,\text{beats/min}$ at rest.

Bradycardia

An abnormally slow heartbeat, defined as less than $60\,\text{beats/min}$ at rest.

Arteries

Thick-walled blood vessels that transport blood under high pressure away from the heart.

Capillaries

The smallest-diameter blood vessels and the sites of exchange of substances between the blood and body cells.

Angiogenesis

The formation of new blood vessels, primarily controlled by Vascular Endothelial Growth Factor (VEGF).

Colloid osmotic pressure

The pressure created by plasma proteins inside capillaries that draws water into the vessels, opposing filtration.

Atherosclerosis

A condition involving deposits of cholesterol plaque on the inner linings of arterial walls.

Systolic pressure

The maximum arterial pressure reached during ventricular contraction.

Diastolic pressure

The minimum arterial pressure remaining before the next ventricular contraction.

Cardiac output

The volume of blood discharged from a ventricle each minute, calculated as $Stroke\,Volume \times Heart\,Rate$.

Peripheral Resistance

The force of friction between the blood and the walls of blood vessels that blood pressure must overcome to flow.

Frank-Starling Law of the Heart

The principle that a greater mechanical stretch of ventricular myocardial cells (preload) results in a greater force of contraction.

Hypertension

Long-lasting elevated arterial blood pressure, often called the “silent killer.”

Central venous pressure

The blood pressure within the right atrium, reflecting its ability to receive blood from the peripheral veins.

Hepatic portal system

A unique venous pathway that drains the abdominal viscera and delivers blood to the liver for processing before it enters general circulation.