cardiovascular Flashcards
What causes the S1 sound and
in what phase of the cardiac cycle does it occur?
- closure of the R & L AV values (tricuspid and bicuspid/mitral)
- beginning of ventricular systole
What causes the S2 sound
and in which phase of the cardiac cycle does it occur?
- closure of the aortic and pulmonic semilunar valves
- marks the end of ventricular systole
When the S2 is split, which valve closes 1st and which closes 2nd?
What causes this split?
- aortic valve closes 1st (A2)
- pulmonic valve closes 2nd (P2)
- Caused by the more muscular left ventricle emptying sooner than R ventricle.
- pronounced splitting is pathologic: RV volume overload (ex: w/ ASD), RV outflow obstruction (pulmonic stenosis), delayed RV repolarization (ex: complete Rt bundle branch block)
Describe S3 and it’s cause
- heard in early diastole
- “Kentucky” cadence
- ventricular gallop
- low pitch
- best heard with bell at apex
Cause: rapid ventricular filling
- can be normal, especially in children
- can be due to fluid overload
Describe S4 and it’s cause
- late diastole sound
- atrial gallop
- “Tennessee” cadence
- low pitched
- best heard with bell at apex
- Caused by forcible atrial contraction against ventricle with decreased compliance
- always abnormal
During ventricular systole, which valves are open and which are closed?
- open: aortic and pulmonic semilunar valves
- closed: mitral and tricuspid (L and R AV valves)
During ventricular diastole, which valves are open and which are closed?
open: tricuspid and bicuspid (mitral) (R & L AV)
closed: aortic and pulmonic valves
What are the possible valvular defects when a systolic murmur is heard?
- aortic stenosis
- pulmonic stenosis
- tricuspid regurgitation
- mitral regurgitation
What are the possible valvular defects when a diastolic murmur is heard?
- tricuspid stenosis
- mitral valve stenosis
- aortic regurgitation (insufficiency)
- pulmonic regurgitation (insufficiency)
describe the grading system for pitting edema
- 1+ 2 mm, rebounds rapidly
- 2+ 4 mm, rebounds within 10-15 seconds
- 3+ 6 mm, rebounds ~60 seconds
- 4+ 8 mm, rebounds after 2-5 minutes
describe the grading system for pulses
0 absent
1 weak, barely palpable
2 normal
3 full, increased
4 bounding
describe the grading system for murmurs
I/VI barely audible in a quiet room
II/VI quiet but clearly audible
III/VI moderately loud, no thrill
IV/VI loud, associated with a thrill
V/VI very loud, easily palpable thrill
VI/VI very loud, palpable and visible thrill, audible with
stethescope off chest wall
What heart sounds are associated with mitral valve prolapse?
- mid-to-late systolic click
- high pitched
- best heard with diaphragm at apex
- may be followed by late systolic murmur if accompanied by mitral regurg
Trace the pathway of the cardiac electrical conduction system
- SA node –>
- AV node –>
- AV Bundle (Bundle of His) –>
- Left and Right Bundle Branches –>
- Perkinje fibers
