Heart sounds and murmurs Flashcards
Portion of stethoscope for high pitched vs low pitched sounds
Diaphragm: high pitched
Bell: low pitched
Where is S1 best heard + characteristics
Near apex of the heart
High pitched
Single sound (composed of M1 and T1)
S2 characteristics
Closure of aortic and pulmonic valves.
A2 and P2 components.
High pitched.
A2 and P2 can dissociate when breathing (“physiologic splitting”)
Ejection click characteristics
Shortly after S1
High pitched, sharp sound
Can be heard in aortic or pulmonic valve stenosis or in dilatation of pulmonary artery or aorta.
Mid- or late-systolic clicks characteristics.
AKA non-ejection clicks
Heard in mitral valve prolapse or tricuspid valve prolapse.
Opening snap characteristics
Diastolic click
Mitral or tricuspid valve stenosis
Sharp and high-pitched
“Hockey stick”
Best heard between the apex and the left sternal border
S3 characteristics
Low-pitched, dull sound
Best heard over cardiac apex
Due to tensing of chordae tendinae during rapid filling of ventricle, or from blood hitting ventricular wall.
Can be normal or abnormal (dilated ventricle)
Another name for pathologic S3
Ventricular gallop
S4 characteristics
Low-pitched, dull sound
Best heart over cardiac apex with left lateral decubitus
Indicative of decreased ventricular compliance due to ventricular hypertrophy or MI
Another name for S4
Atrial gallop
What is a summation gallop
When patient with quadruple rhythm has tachycardia, S3 and S4 coalesce and produce a “summation gallop”.
Long mid-systolic low pitched sound but louder than S1 and S2.
What is a pericardial knock
High pitched sound in patients with constrictive pericarditis.
Early diastolic, can be confused with OS or S3 (between OS and S3, louder than OS).
Occurs when expanding ventricle meets rigid pericardium in diastole.
Does laminar flow emit sound?
No.
Murmurs result from turbulent flow.
5 mechanisms resulting in murmurs
- Stenosis
- Increased flow in normal structure
- Ejection into dilated chamber
- Regurgitation
- Shunting of blood from high to low pressure chamber (ventricular septal defect)
7 hallmarks to describe murmurs
Tiny insects prefer shady little rocks.
- timing (diastole or systole or continuous)
- intensity
- pitch
- shape
- location
- radiation
- response to maneuvers
Describe the grading system, I-VI
I: barely audible (in ER)
II: faint but immediately auadible
III: easily heard, as loud as an S soudn
IV: easily heard and associated with palpable thrill
V: very loud, heard with light sthetoscope pressure
VI: audible without sthetoscope
What are high pitched murmurs caused by
Large pressure gradients, better heard with diaphragm.
Valsalva and standing effect on preload
Decrease preload, which decreases murmurs in regurgitation, stenosis and ventricular septal defects but increases them in HOMC and MVP.
Leg raise and squatting effect on preload
Increase preload, which increases murmurs in stenosis, regurgitation and ventricular septal defects but decreases them in HOMC and MVP.
Hand gripping effect on afterload
Increases afterload, which decreases murmur in AS but increases them in AR, MR, VSD. Decreases also in HOCM and MVP.
Describe systolic ejection murmurs
Aortic or pulmonic valve stenosis.
Begins shortly after S1 and terminates before or at S2.
Crescendo-decrescendo. Later peak = severe stenosis.
What is an innocent systolic murmur?
Benign, resulting from increased systolic flow across normal aortic and pulmonic valves. Disappears when patient sits upright.
What is a pansystolic/holosystolic murmur and what typically causes it?
Mitral valve regurgitation.
Murmur is best heard at the apex, is high pitched and blowing in quality. Often radiates towards left axilla. Intensity does not change with respiration. Can extend beyond S2.
How does inspiration change the murmur heard in tricuspid valve regurgitation?
Intensity of murmur increases with inspiration.
Characteristics of murmurs heard with VSD
Smaller VSD = greater turbulence and louder murmur
What causes a late-systolic murmur, typically?
Mitral valve prolapse. Usually murmur is preceded by a mid-systolic click.
Early diastolic murmurs characteristics
Aortic or pulmonic regurgitation, decrescendo and terminates before next S1. High-pitched.
Pulmonic: intensity increases with inspiration.
Mid- to late- diastolic murmurs characteristics
Due to stenotic mitral or tricuspid valve.
If the murmur is prolonged: severe.
Preceded by an opening snap after S2.
Small peak when the atrium contracts right before S1.
Low pitched
Why can systolic murmur in mitral regurgitation be accompanied by additional diastolic murmur in advanced MR?
Because this causes an increased flow during diastole.
Condition in which there is a continuous murmur
Patent ductus arteriosus (communication between aorta and pulmonary artery).
Due to persistent pressure gradient across two structures.
Murmur hits its peak at S2.
What is a to-and-fro murmur?
Patient with both aortic stenosis and regurgitation. It is not considered a continuous murmur.
Requirements for appropriate BP cuff size
Wide: 40% arm
Length: 80% arm
Small cuff = overestimation or underestimation of BP?
Over.
Loose cuff = overestimation or underestimation of BP?
Over.
Brachial artery below heart = over or underestimation of BP?
Over.
Brachial artery above heart = over or underestimation of BP?
Under.
Why do we always start with palpation when taking the BP?
Because of the auscultatory gap.
How many BP measurements to take to have an accurate one?
Guidelines: 5, take last 1.
Reality: 3, take last 1.
Disease taken into account when diagnosing HTN
Diabetes
Normal BP response to orthostasis
sBP drops slightly, dBP rises slightly
Abnormal BP response to orthostasis
sBP drops >20 mm Hg
dBP drops >10 mm Hg
Which vein do we take for jugular vein pressure and why?
Internal jugular vein because:
- Not valved
- Direct line with RA.
Where does internal jugular vein lie?
Deep to the sternomastoid. Not directly visible.
What does JVP reflect?
Right heart pressure.
How to incline the bed to measure JVP if we anticipate hypovolemia vs hypervolemia
Hypovolemia: head at 0 degrees
Hypervolemia: head at 60-90 degrees.
How to visually distinguish between IJV and carotid?
- IJV: collapses in systole and extends in diastole. Carotid = opposite.
- IJV height of pulsations drop as patient becomes upright. Unchanged in carotid.
- IJV heigh of pulsations fall with inspiration. Unchanged in carotid.
- 2 pulsations in IJV vs 1 in carotid.
Also, IJV is not palpable vs carotid is.
What is considered elevated JVP?
> 3-4 cm above sternal angle or >8-9 above RA
What does rise in height of JVP with inspiration indicate?
Lack of RV compliance.
What is the abdominojugular reflux?
Pressure on the abdominal muscles for at least 10s.
Sustained rise in JVP of >3 cm for at least 15s is a positive response.
What is the apical impulse?
Palpation of the apex.
Most cases = point of maximal impulse.
We assess amplitude and duration. Sustained = hypertrophy.
Palpation of the right ventricular area indications.
High amplitude but not duration: chronic RV volume overload.
High amplitude and duration: chronic RV pressure overload.
