Module 2 - Circulation Flashcards
(37 cards)
How many Valves are there in the heart?
Four
Name the four valves of the heart.
Tricuspid, Pulmonary, Mitral, Aortic.
Which valves control blood flow out of the heart?
Aortic and Pulmonary.
When we listen to the heart we want to know what things?
The valve is properly formed and flexible. The valve should open all the way so that the right amount of blood can pass through. The valve closes tightly so that no blood leaks back into the chamber.
Explain the role of the aortic valve.
Closes off the lower left chamber that holds the oxygen-rich blood before it is pumped out to the body. Opens to allow blood to leave the heart (from the left ventricle to the aorta and on to the body.
Explain the role of the pulmonary valve.
Closes off the lower right chamber (or right ventricle). Opens to allow blood to be pumped from the heart to the lungs (through the pulmonary artery) where it will receive oxygen.
Expain the role of the tricuspid valve.
Closes off the upper right chamber (or atrium) that holds blood coming in from the body.Opens to allow blood to flow from the top right chamber to the lower right chamber (or from right atrium to right ventricle).Prevents the back flow of blood from the ventricle to the atrium when blood is pumped out of the ventricle.
Explain the role of the mitral valve.
Closes off the upper left chamber (or left atrium) collecting the oxygen-rich blood coming in from the lungs. Opens to allow blood to pass from the upper left side to the lower left side (or from the left atrium to the left ventricle).
What are the main components of the cardiac conduction system?
SA node, AV node, bundle of His, bundle branches, and Purkinje fibers.
Where is the SA node located?
Located in the upper part of the wall of the right atrium (the right upper chamber of the heart).
What is the cardiac conduction system?
The cardiac conduction system is a group of specialized cardiac muscle cells in the walls of the heart that send signals to the heart muscle causing it to contract.
Systole
trial or ventricular contraction
Diastole
Atrial or ventricular relaxation
Define AMI.
Acute Myocardial Infarction (MI) is an acute condition caused by prolonged ischemia leading to necrosis of myocardial tissue.
Name the three stages of Myocardial Infarction (MI).
•Ischemia (reversible) •Injury (reversible) •Infarction ( tissue necrosis) irreversible.
What is ischaemia?
ischaemia is a restriction in blood supply to tissues, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive).
On a ECG what characteristics would you see for a STEMI?
Eleveated ST wave, No progression of Q wave, full blockage of the coronary artery.
On a ECG what characteristics would you see for a NSTEMI?
Depressed ST wave or T-wave inversion, no progression to Q wave.
What is a troponin test?
Troponin tests measure the level of cardiac-specific troponin in the blood to help detect heart injury. … When there is damage to heart muscle cells, troponin is released into the blood.
What are troponins?
Troponins are a group of proteins found in skeletal and cardiac muscle fibers that regulate muscular contraction. There are three types of troponin proteins: troponin C, troponin T, and troponin I. Troponin I & T enzyme are released by the cardiac muscle when damaged.
What tropins are releases ny the cardiac muscle when damaged?
Troponin I & T enzyme are released by the cardiac muscle when damaged.
What is considered a positive troponin result?
A Positive result is when 1st trop T is >14-100 and the second trop is 30% greater than 1st. When a person has a heart attack, levels of cardiac-specific troponins I and T can become elevated in the blood within 3 or 4 hours after injury and may remain elevated for 10 to 14 days.
What happens if the SA node does not fire?
Isoelectric line or baseline is the flat line where there are no positive or negative deflections. The SA node is known as the pacemaker of the heart- If it fails to fire the AV node should (hopefully) take over however the rate will be significant decreased.
