bms-251-heart-bms-251-notes-unit-1-professor-bourbina-gvsu

Cardiovascular System

The system that includes the heart and blood vessels, responsible for circulating blood throughout the body.

Function of the heart

To pump blood into vessels to maintain circulation and blood pressure.

Pericardial sac

A double-walled sac containing the heart and the roots of the great vessels.

Atrioventricular (AV) Valves

Valves that separate the atria from the ventricles, preventing backflow of blood.

Chordae tendineae

Tendinous cords that connect the AV valves to the papillary muscles, preventing prolapse.

Semilunar valves

Valves that separate the ventricles from the arteries, preventing backflow into the ventricles during diastole.

Myocardium

The muscular layer of the heart responsible for contraction.

Endocardium

The inner lining of the heart consisting of simple squamous epithelium.

Pulmonary circuit

The route taken by blood from the right atrium to the lungs and back to the left atrium.

Systemic circuit

The route of blood from the left atrium to the rest of the body and back to the right atrium.

Cardiac Cycle

The sequence of events in one heartbeat, including contraction and relaxation phases.

Sinoatrial (SA) node

The natural pacemaker of the heart, which initiates the electrical impulse for contraction.

Electrocardiogram (ECG)

A record of the electrical activity of the heart used to assess heart function.

Cardiac Output (CO)

The amount of blood pumped by a ventricle in one minute, calculated as heart rate times stroke volume.

Bradycardia

A slower than normal heart rate, defined as less than 60 beats per minute.

Tachycardia

A faster than normal heart rate, defined as more than 100 beats per minute.

End-diastolic volume (EDV)

The volume of blood in a ventricle just before contraction.

End-systolic volume (ESV)

The volume of blood remaining in a ventricle after contraction.

Contractility

The strength of contraction of the heart muscle.

Afterload

The resistance the heart must overcome to eject blood during contraction.