Heart Study Guude 2 Flashcards
(50 cards)
Which vessels, part of the coronary/ cardiac circulation, takes blood from capillaries of heart wall to return to the heart? Oxygenated or deoxygenated?
Coronary veins, deoxygenated
What is the root meaning of the word coronary? Why is it named this way?
Coronary= crown because they ( coronary arteries specifically) encircles the heart like a crown on a head.
What’s the word for the connections of arteries that provide an alternate route for blood to reach a particular organ tissue?
Anastomoses
True or false: heart muscle cannot receive sufficient oxygen if one of its coronary arteries is partially obstructed?
False, because the multiple connections of arteries means the heart can receive enough oxygen, even with one of its arteries partially blocked.
This large vein on the posterior surface of the heart, carries carbon dioxide and waste from the heart wall back into the heart at the right atrium.
Coronary sinus
A condition marked by reduced blood flow of the myocardium via the coronary arteries is what ( there is a silent version of this that has no pain prior, is particularly dangerous)? What does it cause?
Myocardial ischemia, results in hypoxia
Condition usually accompanied by severe pain( tightness or squeezing) literally means strangled chest.
Angina pectoris
A complete obstruction of blood flow in a coronary artery may lead to this, results in death of tissue in heart distal to obstruction. Commonly known as a heart attack, weakens heart.
Myocardial infarction
True or false: heart muscle may remain alive in a resting person if it receives only 10-15% of its normal blood supply?
True
Percentage of cardiac fibers that can generate action potentials over and over in a rhythmical pattern? These fibers can continue to stimulate heart even after removed from body.
1%
Is the condition system composed of nervous tissue or modified cardiac muscle cells?
Modified cardiac muscle cells
What feature if the heart is known as the pacemaker of the heart? Sets the pace of action potentials. Where is it located?
Sinoatrial (SA) node, located in right atrial wall
Quickly summarize how action potential pass through the heart, list 5 steps.
SA node, AV node, AV bundle, right and left at bundle, purkinje fibers
How much time elapse from when the atria contracts to when ventricles contract?
Fraction of a second
About how many times does the SA node initiate action potentials per minute? ( this is the fast region of the conduction system)
100 times per minute
How is the SA node slowed when a person is at rest?
Release of actetylcholine ( Ach) can slow SA node
If a SA node becomes damaged or diseased, what takes over peacemaking?
Atrioventricular (AV) node
What is the recording of electrical changes that accompany the heartbeat called?
Electrocardiograph (ekg)
How many recognizable waves are clearly picked up by one heartbeat on an EKG? Name them.
Pwave- atrial depolarization
QRs complex- ventricular depolarization
Twave- ventricular repolarization
Why is the atrial repolarization masked on the EKG?
It’s undistinguishable from the larger QRS complex
What is the name of an abnormal heartbeat rhythm? What caused this?
Arrhythmia, defect in conduction system brought on by defects, stress, drugs
List common symptoms of irregular heartbeat
Chest pain, short breath, light- headedness, dizziness, fainting
Know what a heart block is ( page 583): what happens when the atrial rhythm averages 240-360 bpm?
Atrial flutter
Uncoordinated contractions of the atrial muscles is?
Atrial fibrillation
