Aortic coarctation leads to left ventricular pressure overload and increased left ventricular wall stress. The inability of the neonatal left ventricle to cope with elevated wall stress, results in cardiac failure and calls for immediate surgery. Chronic elevation of left ventricular wall stress stimulation myocardial cell growth and development left ventricular hypertrophy, which might be reversible after relief of the pressure overload. However systemic hypertension and elevated left ventricular muscle mass persist after successful coarction repair. In our Cardiovascular Surgery Department at the University of Istanbul Institute of Cardiology we compared two groups between January 1990-January 1995. The first group was 13 patients of newborn and infants who have operated urgently for isolated aortic coarction and serious left sided heart failure. The control group have had the same specifications exept for they had blood pressure in normal ranges. at the evaluation, tle left ventricle muscle mass and systolic functional changes (ejection fraction, shortening fraction) were examined noninvasively. At the conclusion. the routine follow-up of surgically intervented patients (after min. 3 months, max. 33 month: mean 15 month) who had secondary hypertrophic cardiomyopathy and severely detoriated left ventricle systolic functions, were evaluted as that the left ventricle muscle mass return to normal value and systolic performance of the left ventricle was evaluated as normal or above normal margins.