HEART MURMURS AND SOUNDS Flashcards
What are the auscultatory areas of murmurs?
Aortic area, Pulmonic area, Mitral area, Tricuspid area
Auscultation typically starts in the aortic area and continues in a clockwise fashion.
What is the Levine system for grading the intensity of murmurs?
Grades range from 1/6 (very soft) to 6/6 (extremely loud)
Increased intensity usually reflects increased flow turbulence.
What are the causes of a systolic murmur?
- Ejection: Increased forward flow over valves
- Regurgitation: Backward flow from high to low pressure
Physiologic causes include anemia and exercise; pathologic causes include aortic stenosis.
What are common causes of systolic murmurs?
- Mitral regurgitation (MR)
- Aortic stenosis (AS)
- Tricuspid regurgitation
- Hypertrophic cardiomyopathy (HCM)
- Ventricular septal defect (VSD)
Functional murmurs are also included.
What are common causes of diastolic murmurs?
- Aortic regurgitation (AR)
- Pulmonic regurgitation
- Mitral stenosis (MS)
- Tricuspid stenosis
Diastolic murmurs are usually pathologic.
What is a functional murmur?
Benign findings caused by turbulent ejection into the great vessels
They have no clinical relevance other than being part of the differential diagnosis.
What is the most common systolic ejection murmur of the elderly?
Murmur of aortic sclerosis
Affects 21% to 26% of persons aged 65 and 55% to 75% of octogenarians.
What factors suggest severe aortic stenosis?
- Murmur intensity
- Timing of the murmur
The louder and later peaking the murmur, the worse the condition.
How can physical examination help differentiate functional from pathologic murmurs?
- Golden rule 1: Judge murmurs by the company they keep
- Golden rule 2: Diminished or absent S2 indicates pathology
- Silver rules: All holosystolic, diastolic, and continuous murmurs are pathologic
Functional murmurs are typically short and soft.
What is the grading for a 3/6 murmur?
Easily audible and relatively loud
Grading ranges from 1/6 (soft) to 6/6 (very loud).
Fill in the blank: Aortic stenosis murmur becomes audible when the valvular area is reduced by at least _______.
50%
Significant hemodynamic compromise usually occurs at 60% to 70% reduction.
What are the types of systolic murmurs?
- Early Systolic
- Midsystolic
- Late Systolic
- Holosystolic
Each type has specific causes and characteristics.
What are the causes of continuous murmurs?
- Patent ductus arteriosus (PDA)
- Atriovenous (AV) fistula
- Ruptured sinus of Valsalva aneurysm
Other causes include cervical venous hum and anomalous left coronary artery.
What is the significance of a 60% to 70% reduction in the valvular area in aortic stenosis?
Significant hemodynamic compromise and symptoms usually do not occur until this reduction.
Early to mild aortic stenosis may be subtle at rest.
What factors may suggest severe aortic stenosis?
- Murmur intensity and timing (louder and later peaking indicates worse disease)
- A single S2
- Delayed upstroke and reduced amplitude of the carotid pulse (pulsus tardus et parvus)
The auscultatory findings in mild and severe AS change with disease severity.
What is a thrill in the context of heart murmurs?
A palpable vibratory sensation typical of murmurs caused by very high-pressure gradients, present only in pathologic murmurs with intensity greater than 4/6.
Thrills indicate great turbulence and loudness.
What is isometric handgrip and how does it affect murmurs?
A maneuver that increases peripheral vascular resistance; it intensifies mitral regurgitation (MR) and ventricular septal defect (VSD) murmurs while softening aortic stenosis (AS) murmurs.
A louder murmur with handgrip argues strongly in favor of MR.
What is the Gallavardin phenomenon?
- Atypical AS-like murmur (medium- to low-pitched, harsh, right parasternal)
- A murmur that mimics MR (high-pitched, musical, best heard at the apex)
Reflects different transmission of AS frequencies.
Where is the murmur of hypertrophic cardiomyopathy best heard?
Typically louder at the apex, but may also be louder at the left lower sternal border if septal hypertrophy obstructs both left and right ventricular outflow.
This can cause a differential diagnosis dilemma with mitral regurgitation murmur.
What are the characteristics of a ventricular septal defect murmur?
- Holosystolic, crescendo-decrescendo, crescendo, or decrescendo
- Best heard along the left lower sternal border
- Starts immediately after S1
The type of murmur may indicate the location of the defect in the septum.
What defines a systolic regurgitant murmur?
Characterized by a pressure gradient causing retrograde blood flow across an abnormal opening, such as VSD or an incompetent valve.
Examples include incompetent mitral or tricuspid valves.
What are the auscultatory characteristics of systolic regurgitant murmurs?
- Start immediately after S1
- May have a musical quality
- Do not increase in intensity after a long diastole
This distinguishes them from systolic ejection murmurs.
What are the characteristics of the mitral regurgitation murmur?
- Loudest at the apex
- Radiates to the left axilla
- High-pitched, plateau, holosystolic extending into S2
The intensity and duration of the murmur correlate with the severity of regurgitation.
What distinguishes the acute mitral regurgitation murmur from the chronic one?
Acute MR murmur is often early systolic and can be very short or absent, unlike chronic MR, which is typically holosystolic or late systolic.
80% of acute cases are associated with an S4.
