Match each detailed clinical description of a cardiac murmur and its response to dynamic physiological maneuvers with the correct underlying structural pathology.
- Harsh crescendo-decrescendo systolic murmur at the second right intercostal space; intensity decreases during the strain phase of the Valsalva maneuver and increases with passive leg raise.Aortic valve stenosis
- Harsh systolic murmur at the left lower sternal border; intensity increases during the strain phase of the Valsalva maneuver and decreases with passive leg raise.Hypertrophic obstructive cardiomyopathy
- Blowing holosystolic murmur at the apex; intensity increases with isometric handgrip and decreases with the inhalation of amyl nitrite.Mitral regurgitation
- High-pitched, early diastolic decrescendo murmur at the left third intercostal space; intensity increases with isometric handgrip and decreases during the strain phase of the Valsalva maneuver.Aortic regurgitation
- Late systolic murmur preceded by a mid-systolic click at the apex; the click occurs earlier in systole and the murmur duration lengthens during the strain phase of the Valsalva maneuver.Mitral valve prolapse
Answer
The pairings are as follows: Aortic valve stenosis matches the systolic murmur that softens with Valsalva. Hypertrophic obstructive cardiomyopathy matches the systolic murmur that gets louder with Valsalva. Mitral regurgitation matches the holosystolic murmur that increases with handgrip. Aortic regurgitation matches the diastolic murmur that increases with handgrip. Mitral valve prolapse matches the murmur where the click occurs earlier with Valsalva.
The correct pairings rely on the physiological principles of preload and afterload on valvular pressure gradients. Increased preload (passive leg raise, squatting) generally increases the intensity of flow murmurs (Aortic Stenosis, Aortic Regurgitation, Mitral Regurgitation) but decreases the murmur of Hypertrophic Obstructive Cardiomyopathy and delays the click of Mitral Valve Prolapse. Increased afterload (handgrip) increases the intensity of regurgitant murmurs (Mitral Regurgitation, Aortic Regurgitation) by forcing more blood backward, while decreasing the murmur of Aortic Stenosis and Hypertrophic Obstructive Cardiomyopathy. The Valsalva strain phase profoundly decreases preload, thereby accentuating Hypertrophic Obstructive Cardiomyopathy and moving the Mitral Valve Prolapse click earlier in systole, while softening most other murmurs.
Step-by-Step Solution
Key Concept
Dynamic auscultation uses physiological maneuvers to alter cardiac hemodynamics (preload and afterload), allowing for the clinical differentiation of structurally similar murmurs.
Estimated Time:2m 0s