Patients with isolated coarctation of the aorta were examined by echocardiography be fore operation and in the immediate and remote postoperative period. Before operation all the patients had marked hypertrophy of the myocardium of the left ventricle displayed by an increase in its thickness during the diastole and by an increase in its mass. Besides myocardial hypertrophy, most patients had dilatation of the left ventricle. In the immediate postoperative period a decrease in the dilatation of the left ventricle was noted in patients of the younger age group. The mass of the myocardium did not change in most patients. In the remote postoperative periods a decrease in the mass of the myocardium of the left ventricle was revealed, which was most marked in adult patients.