Exam 1 - Lecture 6 Flashcards
what % of people have the “normal” vasculature structure in the heart?
75%
Left coronary artery splits into
circumflex and LAD
If the circumflex artery is attached to the _____, it’s considered ______
PDA; left coronary dominance
Typically, the PDA is attached to the
right coronary artery
in a small portion of people (10%), the PDA is part of
both circumflex and right coronary artery
Which coronary artery blockage has more serious problems?
Left coronary artery
On PPV, even with low settings, the increased pressure will initially
push the blood out thats in the heart, which increases preload initially, but then the positive pressure decreases venous return to the heart, so then preload decreases
For the initial PPV breath, whats the effects of cardiac output for each side of the heart?
Increases cardiac output for the left side due to increased preload and no changes to afterload..
Right side is a wash because preload and afterload are both increased.
How is cardiac output more effected by PPV?
Long inspiration and higher peep will prolong the time of impedence on venous return, decreasing overall cardiac output
during PPV, most filling for the heart will be
in between inspirations
If we had severe aortic stenosis for 5 years, what happens to the heart? (2 things)
Thicker ventricular walls to get past the bad valve (pathologic hypertrophy)
Leads to less space for filling as well, due to not being as compliant and thicker.
What happens to the graph on filling volume/pressures with pathologic hypertrophy?
The curve is steeper. (Higher pressure and less volume)
If the heart walls are very compliant/stretchy, what happens to the graph on filling volume/pressures?
Much flatter curve… low pressure and higher volume.
What causes dilated cardiomyopathy?
Aortic regurgitation, from the ventricle filling from places at the same time.
For aortic stenosis, what happens to LV pressure during filling?
Less compliance from the left ventricle fighting against the stenotic valve, so that means increased pressure for filling.
For aortic regurgitation, what happens to LV pressure during filling?
More compliance from it being stretched out, so there is less pressure for filling.
Hypertrophy could be related to both
stretched out walls and thickened walls.
Kids have more or less compliant ventricles?
less.
How do kids adapt to venous return?
The heart cant expand its chambers to compensate for venous return, so they arent really volume responsive. They compensate by increasing heart rate.
What is the first heart sound? what kind of pitch?
AV valve closing/ the backwards bulge of the valves closing and the vibration it causes.
Low pitch
What is the second heart sound? pitch?
Aortic valve/pulmonic valve; higher pitch than 1st heart sound
what is the longest heart sound?
1st
Is the atrial heart sound audible?
Not in healthy people. Its audible when atria is doing extra work and more full than normal (mitral stenosis).
what is the 3rd heart sound?
Heard with heart failure or kids since they have low compliance ventricle.
Walls dont stretch to accomodate volume at the end of filling
Heart sounds during aortic stenosis
Systolic murmur, like putting your thumb at the end of a hose.
loudest in the middle
Heart sounds during aortic regurgitation
Diastolic murmur, the backwards flow happens during diastole.
loudest at the beginning, sound trails off towards end of diastole as VENTRICLE GETS FULL/less blood in aorta to backflow.
Heart sounds during mitral stenosis
Disatolic murmur, loudest towards the end due to atrial kick fighting more blood against a stenotic valve.
Heart sounds during mitral regurgitation
Systolic murmur, loudest at the beginning of systole, as the most blood gets pushed back into the atria and atria were empty (less pressure resistance)
The aortic valve can be auscultated where?
2nd ICS, right sternal border, and you can hear it up to the right neck (ejection pathway)
The pulmonic valve can be auscultated where?
2nd ICS, left sternal border and you can hear it up to the left clavicle
The tricuspid valve can be auscultated where?
5th ICS, left sternal border
The mitral valve can be auscultated where?
5th ICS, mid clavicular line
Pnuemonic for auscultation spots for the valves
All Physicians Take Money (in a Z-pattern)
What’s something special that can happen with the 2nd heart sound, and why?
Can have a splitting sound, because the aortic valve and pulmonic valve dont close at the same time. It’s during deep inspiration, and the aorta isn’t affected by it but the pulmonic valve is, so the pulmonic valve closes LATER.
What is the recording instrument that detects frequencies and listens to heart murmurs?
Phonocardiogram
What is the lower frequency limit to healthy hearing?
20Hz
Mediastinum is divided into how many divisions? Where is the divider?
2; superior and inferior; you’ve got the superior mediastinum and then everything below it is the other division
In the inferior mediastinum, how many parts? What are they called?
3, anterior middle and posterior
Anterior mediastinum is
Anything sitting in front of the heart
Middle mediastinum
Heart and most stuff attached directly to it, such as: heart, pericardium, ascending aorta, superior vena cava, pulmonary trunk, pulmonary veins, pericardiacophrenic nerves, phrenic nerves
Whats in the Posterior mediastinum
Abdomen: esophagus, thoracic aorta, thoracic ducts, vagus nerves, azygos vein, hemizygos vein.
What are the pericardiacophrenic nerves?
Responsible for sensory perception in the pericardium as well as supplying innervation to the diaphragm
What does an overdamped art line look like?
No notch
What does an underdamped art line look like?
Too many notches
How does the computer calculate pressure and heart rate for the a line?
By measuring the dichrotic notch
What causes an overdamped art line?
Clot, spring, air, etc. in the art line.
OR the amplifier is too low.
What causes an underdamped arterial line?
Amplifier is too high! Cant figure out the dichrotic notch. Causes artifacts.
Sometimes, the circumflex is a what between what arteries?
Anastomosis between left and right cardiac arteries
Which blood vessels are OUTside the heart?
Epicardial coronary arteries (Only if they can be seen) and those are networked/connected into the deeper vessels.
What are the deeper vessels?
Deep: endocardial
Deepest: subendocardial
Which coronary vessels experience the lowest surrounding pressure?
Epicardial coronary arterials
What coronary vessels experience the most pressure?
Left ventricle subendocardial arterial vessels
Where would ischemia most likely to be in coronary vessels?
Subendocardial left ventricle vessels
Aortic stenosis has which major change in the pressures/volume?
Left ventricle pressure
Mitral stenosis has which major change to pressure/volume?
Increased left atrial pressure due to more pressure required to fill ventricle past bad valve
Whats the major change with aortic regurgitation?
Widened pulse pressure since blood goes back into ventricle.
Whats the major change with mitral regurgitation?
Increased left atrial pressure as systole progresses due to more blood coming back in.
How can you somewhat fix mitral regurgitation?
Reducing afterload, which would decrease pressure in the left ventricle, which prevents some blood from pushing back into atria.
What pathologies is the atrial kick more important?
Aortic stenosis (less compliant ventricle walls = more pressure)
Mitral stenosis (less passive filling)
If the atria pressure increases, what are you at greater risk for?
Can mess up the coordination between ventricles and atria, and can cause atria arrhythmias
What is Eccentric LVH? Causes? Characteristics?
Dilated left ventricle
-dilated cardiomyopathy
-genetic
-Ventricular septal defect
-Systolic dysfunction
-aortic/mitral valve regurgitation
-MI
What is concentric LVH? Causes?
-Thicker walls
-Caused by stenotic aortic valve, long term HTN
-Thicker walls means less compliance, less filling, less stroke volume.
-DIASTOLIC dysfunction because it’s a FILLING problem. It ejects what it has without issue, so it’s NOT a systolic dysfunction.
If we have ischemia in the heart, how can that area adapt? What can reduce likeliness of this adaptation?
Collateral perfusion of the vessels, vessels need to dilate to help bring blood to ischemic area. Smoking, diabetes, chronic htn, pretty much anything that hurts blood flow…
Whats the issue with fibroblasts?
They dont know when to stop laying down heart tissue, and it lays down too much, even over the good cells. Can slow it down by giving ACE-I.
Can cause the heart to stretch out (cardiac myopathy)
What happens if you have nonfunctional heart muscle in the wall?
Bows out and causes systolic stretch, looks like a little bubble. Lowers EF.
