GROWTH AND DEVELOPMENT OF THE VENTRICULAR MYOCARDIUM FROM BIRTH TO ADULT LIFE

Abstract
The evolution of the total ventricular weight, the weight of the right and left ventricles, and the percentage of the right ventricular weight in relation to the total ventricular weight have been studied in the hearts of 165 normal subjects born and living at sea-level, from birth up to the age of 80 years. Up to the age of 7 days the right ventricle weighs more than the left. From birth the weight falls progressively until the 4th month of life. It then begins to increase again, surpassing its birth weight at approximately the 8th month. These findings are discussed in relation to the hemo-dynamic changes that take place in the circulation at birth.