Hypertrophic obstructive cardiomyopathy
This condition is characterized by massive ventricular hypertrophy princi-pally involving the septum. All portions of the left ventricle are affected, although the right ventricle may also be involved. There is myocardial fibrosis resulting in a stiff muscle with decreased distensibility. Ventricular filling is decreased, but systolic pumping is maintained until late in the course of disease. Hypertrophic obstructive cardiomyopathy (HOCM) has been recognized in all age groups and may occur in members of the same family. A dominant pattern of inheritance sometimes is observed.
Most children with HOCM are asymptomatic and are only detected fol-lowing routine clinical examination and the discovery of an incidental heart murmur. Symptoms when present include fatigue and dyspnoea and chest pain and syncope on exertion. HOCM is an important cause of sudden unexpected death.
Unpredictable, especially in those without symptoms.
Avoidance of competitive sports and strenuous activity is encouraged.
Therapy is aimed at reducing the outflow obstruction:
· Medical therapy: beta blocking agents; calcium antagonists, pacemaker.
· Surgical therapy: ventricular septal myotomy, transplantation.