• Hypertrophic Cardiomyopathy

    by  • 23/08/2013 • Cardiology


    Characterised by variable myocardial hypertrophy, most commonly involving the interventricular septum and disorganisation of cardiac myocytes and myofibrils.

    25% patients have left ventricular outflow tract obstruction due to combined effects of:

    1. o Hypertrophy
    2. o Systolic anterior motion of the anterior mitral valve leaflet
    3. o Rapid ventricular ejection


    Symptoms similar to aortic stenosis


    1. o Syncope
    2. o Angina
    3. o Dyspnoea
    4. o Presyncope (typically with exertion)


    1. o Atrial fibrillation – associated with worsening symptoms due to reduction in ventricular filling and an increased risk of stroke.


    Classical physical findings:

    1. o Double apical pulsation (forceful atrial contraction, due to ventricular stiffness – producing a fourth heart sound = S4!)
    2. o Jerky carotid pulse because of rapid ejection and sudden obstruction to left ventricular outflow during systole
    3. o Ejection systolic murmur due to left ventricular outflow obstruction late in systole – it can be increased by manoeuvres that decrease afterload and eg standing, and decreased by manoeuvres that increase afterload and venous return eg squating
    4. o Pansystolic murmur due to mitral regurgitation
    5. o Fourth heart sound



    1. Chest xray
      1. Usually unremarkable
    2. ECG
      1. Left ventricular hypertrophy and ST and T wave changes. Abnormal Q waves
    3. Echocardiogram
      1. Usually diagnostic and in most typical cases shows asymmetric left ventricular hypertrophy, systolic anterior motion of the mitral valve, and a vigorously contracting ventricle.
    4. Pedigree analysis
      1. Reveals autosomal dominant inheritance and may provide prognostic information


    Aetiology – cause, risk factors

    Majority of cases are familial – autosomal dominant.


    Overriding concern in the management is the prevention of sudden death.

    1. o Risk factors for sudden death:
    2. o Massive left ventricular hypertrophy >30mm
    3. o Genotype
    4. o Family history of sudden cardiac death
    5. o Abnormal blood pressure response during exercise
    6. o Non-sustained ventricular tachycardia
      1. The presence of two or more of these risk factors is associated with a substantial risk of sudden death.
      2. Implantable defibrillators effectively prevent sudden death in high-risk cases.


    Chest pain and dyspnoea are treated with beta blockers and verapamil (phenylalkylamine CCB).

    If these are ineffective use disopyramide (class-1 anti-arrhthymic) – used in VT/VF 

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