HOCM

Background

• Autosomal dominant (♂=♀) aymmmetrical septal hypertrophy
• Septal hypertrophy = obstruction but also SAM
• SAM = Systolic Anterior Motion of the anterior leaflet of the mitral valve - the valve hits the hypertrophied septum
• As pressure gradients ↑ (exercise) the obstruction worsens. Coronary vessels are filled during diastole ⇒ ischaemia ±arrhythmia

Clinical

Presents as

Chest pain, palpitations or pre-syncope during excecise.

Ask about FHx of HOCM or sudden cardiac death.

Examination

Look for:

• ↑JVP
• S4 or split second heart sound
• Crescendo-decrescendo systolic murmur (↑ with valsalva)
• Mitral regurg. murmur
• Resp. exam. normal

Investigations

• CXR not indicated - usually normal (rarely shows LVH)
• ECG = LVH (any QRS in any lead >27mm)
• May present as AF or VT
• ECG often normal - Hx important
• Dx in ED = ECHO (defintive = cardiac MRI as out patient)

Management

• If well, in sinus, discharge and GP to refer cardiology OPD
• If AF or VT - call EM senior
• Advise to avoid strenuous exercise until cardiology OPD
• Avoid/stop nitrates/ACEI
• Cardiology OPD may advise β-blockers ±surgery