Auscultation: the five areas and the classic murmurs

1. The five areas

Valve sounds are heard best where the blood flow carries them to the chest wall, not over the valves themselves: aortic area at the right 2nd intercostal space, pulmonary at the left 2nd, Erb’s point at the left 3rd, tricuspid at the left lower sternal edge and mitral at the apex (5th intercostal space, midclavicular line). Tap Listen.

Surgeon’s corner: Find the angle of Louis (manubriosternal joint): the 2nd rib joins the sternum there, and the 2nd intercostal space lies just below it.

2. Aortic stenosis

A stiff, calcified aortic valve makes an ejection systolic murmur, crescendo–decrescendo, loudest at the aortic area and radiating to the carotids. As it tightens, the peak moves later, the second sound softens and the pulse rises slowly.

Surgeon’s corner: Symptoms (angina, syncope, breathlessness) in severe stenosis mean valve replacement — surgical or TAVI — because prognosis without it is poor.

3. Mitral regurgitation

A leaking mitral valve gives a pansystolic, blowing murmur from the first to the second sound, loudest at the apex and radiating to the left axilla (a jet from anterior-leaflet prolapse may radiate to the base instead).

Surgeon’s corner: Acute severe regurgitation (ruptured papillary muscle or chordae) can be soft or silent despite pulmonary oedema: echo, do not rely on the murmur.

4. Aortic regurgitation

Blood falling back through the aortic valve gives an early diastolic, decrescendo, high-pitched murmur, heard best at Erb’s point with the patient sitting forward, breath held in expiration. The pulse collapses and the pulse pressure widens.

Surgeon’s corner: Acute aortic regurgitation with chest pain: think of aortic dissection or endocarditis — a surgical emergency.

5. Mitral stenosis

A narrowed mitral valve, most often rheumatic (calcific in the elderly), gives a loud first sound, an opening snap after the second sound, then a low-pitched mid-diastolic rumble at the apex, best with the bell and the patient turned onto the left side.

Surgeon’s corner: The enlarged left atrium favours atrial fibrillation and clot: anticoagulate with a vitamin K antagonist (not a DOAC) in moderate to severe rheumatic mitral stenosis with atrial fibrillation.