C17: Cardiac Auscultation Flashcards
whats the purpose of performing cardiac auscultation
quick method to detect and track progress of valvular heart disease
why is cardiac auscultation in combination w/ an echo useful for tracking diseases progress?
once the echo is performed the doctor can correlate the present diease state w/ the findings of the echo and if the quality of the murmur changes than it could indicate the disease has progressed (new echo ordered)
which 2 heart sounds arent usually heard
S3 and S4
what does S1 (Lub) represent… what are its 2 parts and which comes first?
- MV and TV closure
- 2 parts are M1 and T1 sounds… M1 before T1 when theres norm conduction through the bundle branches
when might T1 precede M1 in the S1 sound
in a LBBB
why does M1 occur before T1
the LV has higher press than the RV so ventricular press rises faster in the LV
which phases of the cardiac cycle precede and follow S1?
diastole precedes S1 and systole follows
which phases of the cardiac cycle precede and follow S2?
systole precedes S2 and diastole follows
what does S2 (Dub) represent… and what are its 2 parts and which comes first?
- the AV and PV closure
- 2 parts are A2 and P2… A2 before P2
the valves in which side of the heart always close first?
in the L heart
when does the gap b/w A2 and P2 widen and why
There’s increased R heart filling w/ inspiration which causes a change in RV/PA press relationships causes P2 to be delayed
what can be the cause of a very side A2 P2 split
- a RBB
- pulmonary stenosis (valve doesnt open enough so takes longer to exit the ventricle)
- atrial septal defect (takes longer b/c there’s more blood volume in the RA/RV b/c blood is shunted from LA to RA)
when does the S3 sound occur?
is it often heard? when would hearing this heart sound be considered normal vs abnormal?
after the ‘Dub’ (sound is also Ken-tuc-ky)
-not heard often….
- norm in youth, athletes, pregnancy… e.g. those w/ high preload and strong early filling
- abnorm later in life
what causes the S3 heart sound and what phase does it coincide w/
-increased preload… coinciding w/ early filling
NOT caused by valves but Mv is opening at this stage
when does the S4 sound occur?
is it normal?
what does it represent and when does it occur
- presystolic heart sound (precedes S1)
+ not norm
- represents blood being forced into a stiff ventricle from the atria.. indicating that the patient is likely in heart failure
+ occurs in late filling
would an S4 sound occur w/ A fib
No, because the atria arent actually contracting, just fibrillating
which area of the ECG coincides w/ S4
end of the P wave
what are heart murmurs? what causes them
-an abnormal heart sound produced by:
+ turbulent flow
+ high flow rate (eg preg)
+ forward flow through abnormal valves (stenosis)
+ back flow (regurg)
+ abnormal connections (VSD, Patent ductus arterioles)
if a patient had a Patent ductus arterioles, what kind of signal does it often produce w/ cardiac auscultation?
continous signal
why might we not hear a murmur if a patient has an abnormality that would normally cause one?
the flow isnt turbulent enough
does MV prolapse cause a murmur
yes
w/ stenosis, how might the opening of a valve sound
like a click or snapping during opening
are the opening of valves normally silent
yes
why do valves w/ regurg produce murmurs?
what type of sound would be typically hear w/ regurg
because theres turbulent flow when the valve should be closed
-spraying
what are the 6 factors we used to assess and describe murmurs
- which phase
- which portion of the phase
- location where the murmur is best heard
- radiation?… if yes, to where
- quality/shape of murmur
- intensity of murmur
In which intercostal space is the AO valve best heard
2-3rd right intercostal space
Which intercostal space is considered to be the pulmonic area
2-3rd left intercostal space
In which intercostal space is the TV valve best heard
L lower sternal border (approximately 5th intercostal space)
In which area is the MV valve best heard
Apex (approximately the 5th intercostal space on the L near the auxilia)
Where are common areas of radiation
Carotid or apex
What’s the purpose of describing the quality of a murmur
Helpful to relate doppler qualities to the quality of the murmur heard w/ auscultation
What is crescendo and decrescendo?
Crescendo: an increased pitch
Decrescendo: decreased pith
Is pitch often related to velocity
Yes
What does a decrescendo waveform look like
Will have a downward slop
What does a crescendo and decrescendo waveform look like
Will have an arch appearance (equal on both sides)
What type of murmur does a stenotic SV valve create
Crescendo/decrescendo
What type of murmur does a stenotic MV/TV valve create
Diastolic rumble (lower pitch)
What terms describe the phase or duration in which regurgitation would be heard
Holophasic and panphasic
List the intensities of murmurs and clicks and describe them
I: lowest intensity (barely audible)
II: Low intensity
III: Medium intensity (no palpable thrill)
IV: Medium intensity (w/ palpable thrill)… often heard w/ skinny old patients
V: Loud intensity (palpable thrill)
VI: loudest (w/ palpable thrill), heard w/ a stethoscope above the cest
Describe the quality of stenotic murmurs for the AV/PV
- harsh murmur
- radiation
- closing sound may be muted or absent when valve is thickened
Where do AO stenotic murmurs usually radiate to
Carotid
Describe the quality of stenotic murmurs for the MV/TV
During what phase will they be heard?
-heard during diastole… starts w/ and opening snap
- Mv will be heard at the Apex
- low rumbling quality, usually decrescendo
- little radiation w/ stenotic murmurs
Describe the quality of regurg. murmurs for the AV/PV
During what phase will they be heard?
- heard during diastole
- has a blowing or decrescendo sound
Describe the quality of regurg. murmurs for the MV
During what phase will it be heard?
- will occur during systole and be pan or holosytolic
- MV heard at apex w/ radiation to L axilla
- usually loud
Describe the quality of regurg. murmurs for the TV
During what phase will it be heard?
- will occur during systole and be pan or holosytolic
- heard at the left sternal border
what is a rub murmur and what causes it
- beating of the heart against inflamed pericardium (pericarditis) w/o fluid b/w the layers
- cause by tiny crystals in the pericardium
what is a knocking murmur and what causes it
-beating of the heart against hardened pericardium w/ fluid b/w the layers
pericardium is hard from pericarditis
what causes muffled heart sounds
-presence of pericardial effusion… fluid dampens the sound
how can heart changes w. respiration or provocative maneuvers effect heart sounds/murmurs
- Inspiration can cause an : S1-S2 split, paradoxical splitting
- Valsalva increases the intensity of heart sounds.
describe systolic murmurs in general. are they usually pathological?
If they are pathological what could they be caused by
-not usually pathological, can be due to anxiety, nerves…. can be functional
-if pathological they can be:
AS, PS, MR, TR
describe diasystolic murmurs in general. are they usually pathological?
If they are pathological what could they be caused by
-usually pathological
-if pathological they can be:
AR, PR, MS, TS
what is a phonocardiogram
is it used often
- graphic display of heart sounds and murmurs by placing a microphone on the chest
- not used b/c echo is so good
Is any type of pathological regurgitation (AR PR MR TR) always panphasic?
Yes
Why is IVRT prolonged w/ MS?
The valve is thick and it takes longer for it to move and open which prolongs the IVRT
Will any type of stenotic murmur be heard during IVRT AND IVCT?
No
