click below
click below
Normal Size Small Size show me how
firstheartexam
learning about the heart
Question | Answer |
---|---|
mediastinum | in the thoracic, split into two parts, contains the heart, esophagus, trachea, and large blood vessels attached to the heart |
where does the heart start and end? | starts on the second rib and ends on the sixth |
what are the four layers of the heart in order? | endocardium, myocardium, epicardium, pericardium |
endocardium | innermost layer of the heart; thin; smooth |
myocardium | thick middle layer of the heart; allows the heart to pump |
epicardium | outermost layer of the heart; thin |
pericardium | sling-like sac that supports the heart and attaches is to other organs |
what does -edema mean? | swelling |
the heart is a _____ pump? | double |
pulmonic circulation | path of blood that flows from the right side of the heart, through the lungs and back to the left side of the heart |
systemic circulation | path of blood the flows from the left side of the heart to all the organs of the body and back to the right side of the heart |
what do valves do? | they prevent blood from flowing backward |
what are chordae tendinae? | string like structures that keep valves from flowing backward |
what does AV stand for? | atrioventricular |
what do the av valves include? | tricuspid and mitral |
what does SV stand for? | semilunar |
what do the av valves include? | pulmonic and aortic |
what are the sounds the heart makes? | lubb dupp |
what does the "lubb" stand for? | closure of the av valves |
what does the "dupe" stand for? | closure of the sv valves |
what supplies blood to the myocardium? | the coronary arteries |
what does LCA stand for? | Left coronary artery |
what does RCA stand for? | right coronary artery |
what two branches make up the LCA? | left anterior descending and the circumflex |
myocardial cell death is also known as | myocardial infarction |
necrosis means | cell death |
what does infarct mean? | tissue death |
what is ischemia? | inadequate blood flow to the heart, decreasing oxygen supply |
what is angina? | chest pains that occur when your heart doesn't receive enough oxygen |
what is the cardiac conduction system? | provides stimulus for muscle contraction and coordinates the pumping activity for the atria and ventricles by sending electrical signals |
list in order the movement of electrical impulses of the heart | sa node, av node, bundle of his, right and left bundle branch, purkinje fibers |
what does sa stand for? | sinoatrial |
what does av stand for? | atrioventricular |
what does ectopic mean? | any impulse that originates from outside the sa node |
what is an electrocardiogram? | the recording of the electrical activity of the heart |
P wave | reflects the electrical activity associated with atrial depolarization |
what does depolarization mean? | contraction |
QRS complex | reflects the electrical activity associated with ventricular depolarization |
T wave | represents ventricular repolarization |
what is repolarization? | relaxing and filling |
P-R interval | represents the time it takes for the cardiac impulse from the atria to the ventricles |
what is a normal ejection fraction? | 67 percent |
what does EF represent? | the percentage of blood that is pumped out of the ventricle with each beat |
what are the 2 characteristics of cardiac tissue? | automaticity and rhythmicity |
automaticity: | when the cardiac impulse arises from within the cardiac tissue itself |
rhythmicity: | the cardiac tissue fires a cardiac impulse regularly |
what happens when a heart becomes leaky? | it backs up into the chamber where it came from |