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Difficulty: HardCardiovascular System

Match the following structural heart diseases with their characteristic dynamic auscultation findings elicited during physical maneuvers.

  • Hypertrophic obstructive cardiomyopathySystolic crescendo-decrescendo murmur that becomes louder during the strain phase of the Valsalva maneuver due to decreased left ventricular chamber size.
  • Mitral valve prolapseMurmur preceded by a click; the click moves closer to the first heart sound (S1S_1) upon sudden standing.
  • Valvular aortic stenosisSystolic crescendo-decrescendo murmur that becomes softer with isometric handgrip due to a reduced transvalvular pressure gradient.
  • Mitral regurgitationHolosystolic murmur at the apex that becomes louder with isometric handgrip due to increased systemic vascular resistance.

Answer

Hypertrophic obstructive cardiomyopathy corresponds to the murmur that becomes louder with Valsalva strain; Mitral valve prolapse corresponds to the click moving closer to S1S_1 upon sudden standing; Valvular aortic stenosis corresponds to the murmur that becomes softer with isometric handgrip; Mitral regurgitation corresponds to the murmur that becomes louder with isometric handgrip.
Dynamic maneuvers are essential for distinguishing cardiac murmurs by predictably altering hemodynamics. Decreased preload (from the Valsalva maneuver or standing) reduces left ventricular volume, which intensifies the hypertrophic obstructive cardiomyopathy murmur by worsening the outflow obstruction, and causes an earlier click in mitral valve prolapse. Conversely, increased afterload (from isometric handgrip) elevates aortic pressure, which softens the aortic stenosis murmur by decreasing the forward pressure gradient, but intensifies the mitral regurgitation murmur by driving more backward flow.

Step-by-Step Solution

1
Analyze the maneuvers that decrease left ventricular preload (Valsalva strain, sudden standing).
These maneuvers decrease venous return, resulting in a smaller left ventricular chamber size.
To understand their specific effects on volume-dependent dynamic murmurs such as hypertrophic obstructive cardiomyopathy and mitral valve prolapse.
2
Match the preload-dependent pathologies to their corresponding clinical findings.
In hypertrophic obstructive cardiomyopathy, reduced chamber volume worsens the dynamic obstruction, increasing the murmur. In mitral valve prolapse, reduced volume causes the redundant leaflets to prolapse earlier, moving the click closer to S1S_1.
Correctly pairs the first two structural diseases with their physiological responses.
3
Analyze the maneuvers that increase left ventricular afterload (isometric handgrip).
Isometric handgrip primarily increases systemic vascular resistance and aortic pressure.
To determine its divergent effects on fixed stenotic versus regurgitant valvular lesions.
4
Match the afterload-dependent pathologies to their corresponding clinical findings.
In aortic stenosis, increased aortic pressure reduces the forward transvalvular gradient, softening the murmur. In mitral regurgitation, increased systemic resistance forces more blood backward into the left atrium, increasing the murmur intensity.
Correctly pairs the remaining two structural diseases with their physiological responses.

Key Concept

The physiological effects of dynamic auscultation maneuvers (preload and afterload alterations) on the intensity and timing of cardiac murmurs.
Estimated Time:1m 30s
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Topics

Cardiovascular System

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