Cardiovascular function Flashcards
acute coronary syndrome
a constellation of signs and symptoms due to the rupture of atherosclerotic plaque and resultant partial or complete thrombosis within a diseased coronary artery; leads to unstable angina or acute myocardial infarction
afterload
the amount of resistance to ejection of blood from the ventricle
apical impulse
impulse normally palpated at the fifth intercostal space, left midclavicular line; caused by contraction of the left ventricle; also called the point of maximal impulse
atrioventricular (AV) node
secondary pacemaker of the heart, located in the right atrial wall near the tricuspid valve
baroreceptors
nerve fibers located in the aortic arch and carotid arteries that are responsible for control of the blood pressure
cardiac catheterization
an invasive procedure used to measure cardiac chamber pressures and assess patency of the coronary arteries
cardiac conduction system
specialized heart cells strategically located throughout the heart that are responsible for methodically generating and coordinating the transmission of electrical impulses to the myocardial cells
cardiac output
amount of blood pumped by each ventricle in liters per minute
cardiac stress test
a test used to evaluate the functioning of the heart during a period of increased oxygen demand; test may be initiated by exercise or medications
contractility
ability of the cardiac muscle to shorten in response to an electrical impulse
depolarization
electrical activation of a cell caused by the influx of sodium into the cell while potassium exits the cell
diastole
period of ventricular relaxation resulting in ventricular filling
ejection fraction
percentage of the end-diastolic blood volume ejected from the ventricle with each heartbeat
hemodynamic monitoring
the use of pressure monitoring devices to directly measure cardiovascular function
hypertension
blood pressure that is persistently greater than 140/90 mm Hg
hypotension
a decrease in blood pressure to less than 100/60 mm Hg that compromises systemic perfusion
murmurs
sounds created by abnormal, turbulent flow of blood in the heart
myocardial ischemia
condition in which heart muscle cells receive less oxygen than needed
myocardium
muscle layer of the heart responsible for the pumping action of the heart
normal heart sounds
sounds produced when the valves close; normal heart sounds are S1 (atrioventricular valves) and S2 (semilunar valves)
opening snaps
abnormal diastolic sound generated during opening of a rigid atrioventricular valve leaflet
postural (orthostatic) hypotension
a significant drop in blood pressure (20 mm Hg systolic or more or 10 mm Hg diastolic or more) after an upright posture is assumed