Lecture 6 Flashcards
Exam 1 content
What is right coronary dominance?
PDA branches from the RCA
What is left coronary dominance?
PDA branches from the circumflex
% of population that is right coronary dominant and % left coronary dominant
right: 75%
left: 15%
The rest of the population has a branch off both
Which form of coronary dominance is more dangerous? why?
left coronary dominance is more dangerous because more of the heart muscle relies on one vessel (less collateral flow). Left coronary dominance makes angioplasties and CABG much more risky
What do you expect to see with positive pressure breathing relative to CO?
you are increasing pressure in the thorax which increases preload and CO at first.
What does positive pressure ventilation do to venous return?
decreases VR (increased PAP and increased afterload on the right heart).
When does the heart fill with blood during positive pressure ventilation?
during expiration to just before the next inspiration (positive pressure)
What causes pathologic left ventricular hypertrophy (less compliant)?
aortic stenosis, chronic hypertension. Kiddos also have less compliant left ventricles.
What causes dilated left ventricular cardiomyopathy (stretched out, very compliant)?
aortic valve regurgitation
What is eccentric LV hypertrophy?
dilated LV (thin walls)
What is concentric LV hypertrophy?
increased wall thickness in LV
What causes the first heart sound? How long does it last?
AV valves close. It lasts 0.14 sec. Low pitched.
What causes the second heart sound? How long does it last?
Aortic valve closing. It lasts 0.11 sec. and is higher pitched.
What is the fourth heart sound?
“atrial kick” shouldn’t hear this in healthy people, but you could hear it with mitral stenosis.
What is the third heart sound?
You can hear this with a low compliance ventricle (kids, aortic stenosis).
With what pathology would you hear a systolic murmur?
aortic stenosis, mitral regurgitation and anemia
How could you differentiate a systolic murmur caused by aortic stenosis versus mitral regurgitation?
The systolic murmur will be loudest at the beginning of systole and tails off at the end of systole for mitral regurgitation. The murmur associated with aortic stenosis will be loudest period d/t tons of turbulence
When would you hear a diastolic murmur?
aortic regurgitation, mitral stenosis
How could you differentiate a diastolic murmur caused by aortic regurgitation versus mitral stenosis?
the diastolic murmur associated with mitral stenosis is much louder at the end of diastole. Aortic regurg would be loudest at the beginning of diastole.
Where can you auscultate the aortic valve?
R side of sternum 2nd ICS. Or the right side of the neck.
Where can you auscultate the pulmonic valve?
L side of sternum 2nd ICS.
Where can you auscultate the tricuspid valve?
medial left side of the patient in the 5th ICS.
Where can you auscultate the mitral valve?
lateral left side of the patient in the 5th ICS.
What is the pneumonic we learned to remember the order to auscultate the 4 different heart valves?
“All Patients Take Meds”
