HOCM

• Hypertrophic cardiomyopathy

  • Asymmetrical increase in left ventricular wall thickness
  • Not solely explained by abnormal loading conditions (commonly hypertension and aortic stenosis)
  • Inherited via autosomal dominant pattern with mutations in cardiac sarcomere proteins
  • Commonly presents in young adults - leading cause of sudden cardiac death in this age group
• Disease characteristics:

  • Left ventricular wall thickening - typically of the septum
  • Myocardial fibrosis
  • Most commonly presents in third decade of life
  • More common in men
• Important to ask if there is any family history of sudden cardiac death
• Symptoms:

  • Most people do not have symptoms and diagnosis is incidental
  • Dyspnoea - due to LV diastolic dysfunction and resultant pulmonary oedema
  • Syncope and presyncope
  • Chest pain
  • Palpitations - due to arrhythmias, both supraventricular and ventricular in origin
• Clinical exam:

  • Systolic ejection murmur loudest between the apex and left sternal border - due to left ventricular outflow tract obstruction
  • Fourth heart sound
  • Mitral regurgitation murmur
  • Double apical beat
  • Lateral displacement of the apical pulse
  • Prominent A wave
• Bedside investigations:

  • Blood pressure - exclude hypertension
  • ECG - increased voltages in precordial leads and non specific ST segment and T wave abnormalities
  • Ambulatory ECG - initial risk assessment to look for arrhythmias
• Imaging:

  • Echocardiogram is first line
  • Cardiopulmonary exercise testing
• Management:

  • Angina - beta blocker or calcium channel blocker
  • If left atrium enlarged, should be tested for AF. Flecainide and digoxin to be avoided. Warfarin is the anticoagulant of choice.
  • HF - cardiac transplantation can be considered
  • ICD - primary prevention if high risk of sudden cardiac death or secondary prevention if cardiac arrest from arrhythmia
  • Septal reduction therapy