Tetralogy of Fallot is most often associated with which murmur?

• A. Pansystolic murmur at apex
• B. Harsh systolic murmur best heard at left upper sternal border
• C. Continuous murmur at left infraclavicular area
• D. Midsystolic click at apex

Answer: (B)

Tetralogy of Fallot produces obstruction of the right ventricular outflow tract, creating a pressure gradient during systole. That results in a harsh, systolic ejection murmur best heard along the left upper sternal border, where the RVOT and pulmonary valve sit. This murmur reflects the RVOT obstruction rather than a murmur from regurgitant lesions or continuous flows. The other murmurs described fit different conditions (pansystolic at the apex → mitral/tricuspid regurg, continuous murmur at the infraclavicular area → patent ductus arteriosus, midsystolic click → mitral valve prolapse). So the harsh systolic murmur at the left upper sternal border is most characteristic of Tetralogy of Fallot.