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The Cardiovascular System

Glossary

Acute myocardial infarction (AMI or MI) commonly known as a heart attack, is a disease state that
occurs when the blood supply to a part of the heart is interrupted. The resulting ischemia or oxygen
shortage causes damage and potential death of heart tissue. Aorta: the largest of the arteries in the
systemic circuit
Aortic Valve: lies between the left ventricle and the aorta
Antidiuretic hormone: Produced in the posterior pituitary ADH (vasopressin), major function is to
regulate blood pressure by water retention by the kidneys.
Arteriole: a small diameter blood vessel that extends and branches out from an artery and leads to
capillaries
Atrial natriuretic peptide: Produced in the atria of the heart, it increases urinary excretion of sodium
which causes water loss which in turn the viscosity of the blood is lowered and in turn lowers the blood
pressure.
Atrioventricular Node (abbreviated AV node): the tissue between the atria and the ventricles of the
heart, which conducts the normal electrical impulse from the atria to the ventricles
Atrioventricular valves: large, multi-cusped valves that prevent backflow from the ventricles into the
atria during systole
AV Bundle: collection of heart muscle cells specialized for electrical conduction that transmits the
electrical impulses from the AV node
Barbiturates: CNS depressants, sedative-hypnotics
Blood Pressure: the pressure exerted by the blood on the walls of the blood vessels
Capillaries: the smallest of a body’s vessels, they connect arteries and veins
Cardiac Cycle: term used to describe the sequence of events that occur as a heart works to pump blood
through the body
Cerebral Vascular Accident (CVA): Also known as a stroke, is a rapidly developing loss of a part of
brain function or loss of conciousness due to an interruption in the blood supply to all or part of the
brain. That is, a stroke involves the sudden loss of neuronal function due to a disturbance in cerebral
perfusion. There are many different causes for the interruption of blood supply, and different parts of
the brain can be affected. Because of this, a stroke can be quite heterogeneous. Patients with the same
cause of stroke can have widely differing handicaps. Similarly, patients with the same clinical handicap
can in fact have different causes of their stroke.
Chordae Tendinae: cord-like tendons that connect the papillary muscles to the tricuspid valve and the
mitral valve in the heart
Coronary Arteries: blood vessels that supply blood to, and remove blood from, the heart muscle itself
Continuous Capillaries: have a sealed epithelium and only allow small molecules, water and ions to
diffuse
Deep-vein thrombosis (DVT): is the formation of a blood clot ("thrombus") in a deep vein. It
commonly affects the leg veins, such as the femoral vein or the popliteal vein or the deep veins of the
pelvis. Occasionally the veins of the arm are affected
Diastole: period of time when the heart relaxes after contraction in preparation for refilling with
circulating blood
Diastolic Pressure: lowest point in blood pressure where the heart relaxes
Edema: The swelling that forms when too much tissue fluid forms or not enough taken away
Electrocardiogram: the recording of the heart's electrical activity as a graph
Epinephrine: Produced in the adrenal medulla of the adrenal glands, major function is
vasoconstriction that will in turn increase respiratory rate and increase cardiac out put.
Fenestrated Capillaries: have openings that allow larger molecules to diffuse

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