Murmurs Flashcards
What is a murmur?
direct result of blood flow turbulence
The amount of turbulence =
intensity of the murmur
Where are mitral murmurs best heard at?
the apex
Atrial septal defect is ________
diastolic
Ventricular septal defect is ______
systolic
Intensity of a murmur
determined by the quantity and velocity (turbulence)
Factors that affect turbulence of a murmur
The size of the orifice or vessel through which the blood flows
The pressure difference (gradient)
The volume of blood
The transmission of intensity of a murmur is also dependent on the characteristic of tissue between the blood flow and the stethoscope. Explain high and low intensities
Higher intensity: Low BMI individuals
Lower intensity: Air (emphysema), fluid (pericardial effusion), fat (high BMI)
What are the grades of intensity of a murmur and what does each mean?
Grade I: very faint
Grade II: soft murmur, readily detectable
Grade III: loud but no palpable thrill
Grade IV: loud with palpable precordial thrill
Grade V: very loud, audible with stethoscope lightly on the chest with a palpable precordial thrill
Grade VI: loudest murmur, audible WITHOUT a stethoscope, + palpable thrill
Describe pitch, high/low
High pitch: best heard with diaphragm
Low pitch: best heard with bell
Describe what the quality of a murmur can be
Harsh, rumbling, blowing, musical
What are configurations of murmurs?
Configuration: The time course of murmur intensity
Crescendo: Increasing
Decrescendo: Decreasing
Crescendo-decrescendo: Increases then decreases
Plateau: Intensity doesn’t change
How is the duration of a murmur assessed?
by determining the timing of the murmur relative to the cardiac cycle
What are systolic murmurs?
starts with or after S1 and terminates with or before S2
Early systolic murmur
Obscures S1, does not extend to S2
Mid systolic murmur
begins after S1, ends before S2 (both S1 and S2 easily audible)
Holosystolic (pansystolic) murmur
obscures both S1 and S2, lasts entire duration
Late systolic murmur
starts after S1, extends to S2
What are systolic murmurs?
Mitral regurgitation
Tricuspid regurgitation
Aortic stenosis
Pulmonic stenosis
Ventricular septal defect
Hypertrophic obstructive cardiomyopathy
Mitral regurgitation
The mitral valve is a bicuspid valve
The valve opening is enclosed by a fibrous ring = mitral valve annululs
The mitral valve leaflets are attached to chordae tendineae
Tendon-like projections that prevent prolapse of leaflets and regurgitation of blood back into the left atrium
The chordae tendineae are further attached to papillary muscles that attach to the left ventricular walls
What is mitral regurgitation caused by?
a leaky, or incompetent, valve causing backwards flow of blood from the left ventricle into the left atrium
What are the primary causes of mitral valve regurgiation?
Mitral valve prolapse
Ischemic (coronary artery disease)
Rheumatic heart disease
Endocarditis
What are the secondary causes of mitral valve regurgitation?
The result of progressive enlargement of the left ventricle leading to mitral annular dilatation and displacement of the papillary muscles
Mitral valve regurgitation (systolic murmur)
Timing: Early systolic or holosystolic
Location: Apex
Radiation: Axilla
Intensity correlates with severity
Quality: High pitched, blowing
Pitch: Medium
For the mitral regurgitation (systolic murmur), ______ is soft due to poor closure of the MV
S1
During the mitral regurgitation (systolic murmur), ________ and _______ are present due to volume overload
ventricular gallop (S3), atrial gallop (S4)
What are the associated clinical findings with mitral regurgitation (systolic murmur)
Hyperdynamic or displaced apical impulse (PMI)
Heart failure if degree of MR is severe
Atrial fibrillation is common
What is mitral valve prolapse?
the mitral valve may have redundant or elongated chordae tendineae causing an abnormal ballooning of the mitral valve leaflets during systole
MVP is associated with a ______ click
systolic, as the leaflets snap back into place
MVP is associated with a murmur ONLY when ______ is present as well, typically mid to late systolic
Mitral regurgitation
What is the most common cause of mitral regurgitation?
MVP
What is aortic stenosis?
The normal aortic valve opens completely during systole, allowing outflow of blood from the LV
Aortic leaflets will calcify over time, causing the valve to narrow
The aortic valve is usually _______ but can also be ________ or ________
tricuspid, bicuspid or unicuspid
Symptom onset of valvular aortic stenosis
Unicuspid: early childhood
Bicuspid: 40-70 years of age
Tricuspid: 70+
Aortic stenosis (systolic murmur)
Timing: Midsystolic, crescendo-decrescendo
Location: Right 2nd intercostal space (aortic area)
Radiation: Neck
Intensity correlates with severity
Quality: Harsh, rough
Pitch: Low, but becomes high pitched when very severe
T/F Aortic stenosis has thrills that may be palpable
True
Aortic stenosis has complete loss of _______
S2
Aortic stenosis has an early ___________ due to heavily calcified valve
systolic click
What are the associated clinical findings with aortic stenosis?
Angina
Syncope
Exertional dyspnea
Heart failure
Ventricular septal defect is a _______ defect
congenital
What type of murmur is VSD?
holosystolic from a continuous right shunt during systole
VSD is _______, often easily detectable
loud
Which murmur can many patients tolerate into adulthood with good functional status?
VSD
VSD(stytolic murmur)
Timing: Holosystolic
Location: Left or right 3rd/4th intercostal spaces
Radiation: left clavicle
Intensity: Loud, may have a thrill
Quality: Harsh
Pitch: low pitch – small defects ; high pitch – larger defects
What is tricuspid regurgitation?
Backwards flow of blood from the right ventricle back into the right atrium during systole
What are the primary causes of Tricuspid regurgitation?
- Endocarditis
- Myocardial infarction > RV dilatation >valve incompetence
- Right ventricular pacemaker leads (iatrogenic)
What are the secondary causes of tricuspid regurgitation?
Pulmonary artery hypertension
Tricuspid regurgitation (Systolic murmur)
Timing: Holosystolic
Location: Left lower sternal border, 4th intercostal space (tricuspid area)
Radiation: Epigastric area
Intensity: Increases during inspiration due to increased right sided venous return, decreased with Valsalva
Quality: soft, often difficult to hear
Pitch: High pitch
What are the associated clinical findings with tricuspid regurgitation?
- PMI may be displaced to epigastric area if RV very enlarged
- May have a wide split S2
- S3 or S4 originating from the right side of the heart
- Findings consistent with right heart failure
-JVP
-Ascites, abdominal distension
-Lower extremity edema
