Hypertrophic Obstructive Cardiomyopathy

Hypertrophic obstructive cardiomyopathy:
Characterised by ;
1. Asymmetric hypertrophy of IVS
2. Systolic anterior motion of mitral valve
3. Dynamic obstruction of left ventricle
Patient usually present with dyspnoea,anginal pain,fatigue and syncope. Sometimes sudden death occurs.
Double or triple apical impulse may be seen and there occurs rapid carotid upstroke, S4 may be heard
Systolic crescendo decrescendo diamond shaped murmur heard at lower left sternal border
Diagnosis made by echocardiography
Valsalva maneuvre , nitrate inhalation , handgrip and standing increase the intensity of murmur.
Beta-blockers are helpful in treatment


Drugs contraindicated in HOCM:
Digitalis, beta-agonists, sympathomimetic amines, nitrates, diuretics


Causes of reversible dilated cardiomyopathies:
Alcohol abuse, Pregnancy, throid disease, cocaine use and chronic uncontrolled tachycardia


Holiday heart syndrome:

Usually occurs after a alcoholic binge, Characterised by atrial fibrillation, atrial flutter and VPCs.


Peripartum cardiomyopathy:
Seen in last trimester or first six months after delivery.


Drug induced cardiomyopathy:
Doxorubicin (adriamycin) induced CMP causes cardiomyopathy when given in dose of >550mg/m2
Other risk factors include irradiation, age>70 years, underlying heart disease, HT, treatment with cyclophosphamide
To reduce toxicity, either drug is given slowly or given with some iron chelator ( dexrazoxone)
Cyclophosphamide may cause cardiotoxicity and development of CHF , characterized by myocardial oedema and hemorrhagic necrosis