15 - Cardiomyopathies

Summary

This chapter describes the classic cardiomyopathies: hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, and left ventricular (LV) non-compaction. Patients with hypertrophic cardiomyopathy have a histological appearance of hypertrophy, sarcomeric disarray, and interstitial fibrosis. Outflow tract obstruction may be reduced non-surgically by alcoholic septal infarction. This technique is based on the principle that infarction of the upper septum leads to resolution of LV outflow obstruction and LV hypertrophy, and improvement of diastolic function. Restrictive cardiomyopathy is a sarcomeric cardiomyopathy. LV non-compaction is a sarcomeric cardiomyopathy affecting children and adults. The presenting features include heart failure, arrhythmias, and thromboembolism. Mutations in genes coding for several proteins have been identified in LV non-compaction. Although echocardiography forms only one part of the assessment of a patient with a cardiomyopathy, it is a valuable tool in discriminating between the various cardiomyopathies.