During a pre-participation examination, which heart murmur finding would be a concern requiring referral to a cardiologist?

During a pre-participation examination, which heart murmur finding would be a concern requiring referral to a cardiologist?

• A. A murmur that is louder when squatting and softer when standing
• B. A murmur that is quieter when squatting and louder with a Valsalva maneuver
• C. A murmur with narrow and variable splitting of S2
• D. A systolic murmur that is grade 1 or 2

Answer: (B)

In a pre-participation exam, how a murmur changes with specific maneuvers helps distinguish benign flow murmurs from pathologic ones. A pattern where the murmur becomes louder when preload is reduced (during a Valsalva maneuver) and becomes quieter when preload is increased (with squatting) points to dynamic LV outflow tract obstruction, most classically hypertrophic obstructive cardiomyopathy. HOCM is a serious condition in athletes because it can lead to sudden cardiac events, so this finding prompts referral to cardiology for further evaluation, typically including an echocardiogram and risk assessment. Other murmurs described would not raise the same red flag in this context. For example, a murmur that tightens with squatting and softens with standing fits benign flow murmurs seen in healthy individuals, and a murmur with variable S2 splitting or a mild, low-grade systolic murmur can also be benign variants in many young people.

In a pre-participation exam, how a murmur changes with specific maneuvers helps distinguish benign flow murmurs from pathologic ones. A pattern where the murmur becomes louder when preload is reduced (during a Valsalva maneuver) and becomes quieter when preload is increased (with squatting) points to dynamic LV outflow tract obstruction, most classically hypertrophic obstructive cardiomyopathy. HOCM is a serious condition in athletes because it can lead to sudden cardiac events, so this finding prompts referral to cardiology for further evaluation, typically including an echocardiogram and risk assessment.

Other murmurs described would not raise the same red flag in this context. For example, a murmur that tightens with squatting and softens with standing fits benign flow murmurs seen in healthy individuals, and a murmur with variable S2 splitting or a mild, low-grade systolic murmur can also be benign variants in many young people.