Examination of the Cardiovascular System Flashcards
Where is S1 the loudest, and why? When does splitting occur?
Loudest over mitral area -> LV apex, because S1 is caused by the closing of the AV valves at the beginning of systole.
No splitting should ever occur in S1
What is S2 best heard and why? What time in the cardiac cycle does this correspond to?
Best heard at the left upper sternal border, since the pulmonic valve tends to have a quieter closing than aortic valve, so you listen it its area
Corresponds to the beginning of diastole (isovolumic relaxation)
When is an aortic ejection click heard in the cardiac cycle? In what pathology is it typically heard?
Heard just after S1 -> just after beginning of systole.
Typically heard in bicuspid aortic valve -> will snap open aggressively
Ejection click will be lost with worsening calcification (cannot be ripped open so fiercely)
Best heard in right 2nd ICS (aortic area)
What is the mitral stenosis opening sound and when is it heard? Where is it best heard?
Opening snap best heard at apex of heart
Occurs just after S2
How do you tell a mitral stenosis opening snap apart from an S3?
Mitral stenosis - high-pitched, best heard with diaphragm
S3 - Low-pitched, best heard with bell
What causes S3? When does it occur?
Like opening snap - early diastole
Due to sudden ventricular distension due to rigorous rapid filling
When is S3 pathologic vs not pathologic?
Not pathologic in: Children and young adults, athletes
Pathologic: States w/increased filling pressures - Heart failure, mitral regurgitation, dilated ventricles
What causes S4 and when is it pathologic vs not pathologic? When does it occur in the cardiac cycle?
Occur in late diastole when atrial contracts to push blood against a stiff ventricle
ALWAYS pathologic
What can S4 be easily confused with and how do you tell them apart?
S4 - easily confused with aortic ejection click
S4 is best heard at apex of heart in left lateral decubitus position
Aortic ejection click is best heard in the aortic area
When does physiologic splitting of S2 typically occur, and why?
Typically occurs during inspiration, because decreased intrathoracic pressure causes blood to fill lungs and right ventricle, increasing pulmonary pressures. This delays P2. Normal splitting has P2 later than A2.
Splitting often goes away during expiration, which LV filling is increased, and RV pressure is decreased, allowing A2/P2 to close at the same time.
What is the first part of the cardiac exam? Why is this important?
Inspection of the jugular venous pulsations -> important because the jugular vein is a surrogate for right atrial pressure
What are the three major jugular waves and what causes them? Which one is most liable to be absent?
These are transient rises in venous pressure seen as bulging
a wave = atrial contraction
c wave = carotid pulse pressing against vein / bulging of triscupid valve into atrium
v wave = venous return into left atrium peaking just before AV valves open during early diastole
C wave often absent, so it will just look like two pulses
What causes the pressure to drop in the right atrium between the a/c and c/v waves?
This is called the x descent
-> due to contraction of ventricles and subsequent dilatation of the atria towards these ventricles, leading to a drop in pressure
What is the value of the JVP at the sternal angle of Louis, and what is the best way to measure the JVP above this?
5cm at sternal angle
Measure the extra height of the venous blood column by putting the patient at 45 degree angle, and measuring the height of the JVP pulse above that, measured parallel to the ground
Where do you measure the JVP?
Between the clavicular and sternal heads (posterior and anterior heads) of the SCM, and the clavicle.
This is the “jugular triangle” -> where you may be able to two pulsations per beat of the internal jugular vein.
Can also measure the JVP via the external jugular vein, which will be more lateral and over the SCM -> okay because they are contiguous.
What does a large a wave indicate? When will the a wave disappear?
Large a wave -> Tricuspid stenosis -> blood backs up during atrial contraction
a wave disappears in atrial fibrillation -> no atrial contraction
What can cause a large v wave?
Tricuspid regurgitation (extra venous pressure during systole)
What should you be looking for when inspecting the precordium?
Scars (i.e. a past sternotomy for CABG), bulges (i.e. pacemakers, closer to axilla), abnormal pulsations (especially at apex)
What does the pulse amplitude correlate with?
Pulse pressure -> the difference between diastolic and systolic
Will be elevated in aortic regurgitation (widened), and decreased in aortic stenosis (narrowed)
A normal pulse upstroke is brisk. What does a slow upstroke indicate?
Aortic stenosis (crescendo-decrescendo murmur)
What type of valvular problem is indicated via palpable thrills? Anything else? Where are they best felt?
Stenosis -> pulmonic or aortic. These are vibrations
Also small VSDs with turbulent flow
Best felt at left sternal border
What is the normal point of maximal impulse (PMI)? What position should the patient be in? Give the following characteristics: Location, diameter, amplitude, duration.
Location: LV apex
Diameter: Quarter size
Amplitude: small, brisk
Duration: Brief
What happens to the PMI in dilated cardiomyopathy?
It is displaced laterally and inferiorly, and the size is much larger -> silver dollar sized
In what condition will the PMI have a longer duration?
LV hypertrophy
What does a parasternal heave indicate?
Elevated RV pressure, usually due to pulmonary hypertension
What do palpable aortic pulsations in the suprasternal notch of young thin adults and older adults indicate?
Young thin adults - normal
Older adults - ascending aortic aneurysm
Where is aortic regurgitation best heard?
Left sternal border -> especially 3rd ICS
-> THIS IS COUNTERINTUITVE. Everything else is normal.
What is the best way to hear S3/S4 and mitral murmurs?
With patient in left lateral decubitus position
What is paradoxical splitting of S2 and why does it happen?
When S2 splits during expiration, happens due to conditions where A2 closes later than usual, as in aortic stenosis or left bundle branch block
What is wide splitting and why does it happen?
Exaggerating normal splitting -> splitting heard on expiration and even more on inspiration
Happens due to conditions causing a delay in RV emptying, including pulmonic stenosis and right bundle branch block
What is fixed splitting and why does it happen?
Closure of pulmonic valve is consistently delayed, with no regard for inspiration / expiration
Happens typically due to atrial septal defect causing a left to right shunt
What causes a mid-systolic click and when is it best heard?
Sudden tensing of deformed, redundant mitral valve or triscupid valve (mitral or tricuspid prolapse)
Best heard in that valvular area (i.e. cardiac apex = mitral)
What pathologies can an S4 be indicative of, and when is it always absent?
Conditions of a stiff left ventricle due to hypertrophy
- Hypertension
- Aortic stenosis
Absent: Atrial fibrillation
How are murmur intensities graded?
Grade 1-3: Based on loudness. 1 is barely audible, 3 is loud
Grade 4+: Palpable thrill is associated
What murmur is aortic stenosis associated with? Where does it radiate to? What should you listen with?
Mid-systolic murmur, often crescendo-decrescendo, with an ejection click. Heard best at aortic area.
Radiates to the carotids.
Listen with diaphragm -> high pressure
What murmur is mitral valve prolapse with mitral regurgitation associated with? How and where is it best heard? Does it radiate?
Late systolic crescendo murmur following mid-systolic click
Heard best via the diaphragm at the apex (high pressure = high pitch)
Does not radiate
What murmur is associated with chronic mitral regurgitation? Where is it best heard? Does it radiate?
Holosystolic, blowing murmur
Best heard at the apex, mediumpitched so audible no matter what.
Radiates to axilla
What murmur is associated with aortic regurgitation? Where and how is it best heard? Does it radiate?
Decrescendo diastolic murmur (lessens as arterial pressure dissipates)
Best heard at 3rd LICS with diaphragm (high pressure) with patient leaning forward at end exhalation (patient has just exhaled and pushed all of his blood into LV, and it’s going to push backward after leaving aorta)
Does not radiate
What murmur is associated with mitral stenosis? Where and how is it best heard? Does it radiate?
Low-pitched, diastolic rumble best heard at apex in LLDP
Associated with an opening snap best heard in same place, but with diaphragm (high pitch)
What heart sounds can result from a VSD?
More exaggerated RV S3 due to left-right shunt, also flow rumble at left ventricular apex due to shunt.
What pathology will cause a constant murmur throughout systole and diastole? When will it be loudest?
Patent ductus arteriosus, as blood rushes from aorta to pulmonary artery
Loudest around S2, which is end systole early diastole, when the pressure in the aorta is the highest. S2 will often be difficult to detect.
What causes a pericardial rub and what are its three components? Best heard?
Friction caused by inflamed serosal surfaces rubbing together (pleural rubs may also occur)
All three occur when ventricles are very distended:
- Late diastole - atrial contraction
- Systole - ventricular contraction
- Early diastole - isovolumic relaxation
Often only 1 or 2 components may be heard - best over left lateral sternal border
What causes knocks and when do they occur? What is their frequency? Best heard?
High frequency, sharp diastolic sounds best heard at apex, occurring early in diastole (similar timing to S3)
Thus, they may confused with an opening snap
-> sudden tensing of pericardium during rapid filling, as in constrictive pericarditis
What is a bruit and how is it best heard? What does it indicate?
Medium-high pitched murmurs over a blood vessel, best heard with diaphragm
Indicates turbulent blood flow due to vascular stenosis (i.e. femoral bruit)
When are bruit typically loudest, and when might this not be the case?
Loudest during systole
Can be continuous if you have an AV communication (i.e. AV fistula) -> as in dialysis
