Explanation
•Stenosis of the aortic valve prevents blood from passing freely from the left ventricle of the heart into the aorta.
•It causes pressure in the heart as the heart attempts to force blood through the narrowed valve and therefore leads to hypertrophy of the left ventricle. If left ventricular failure occurs, pressure in the left atrium increases, resulting in back pressure in pulmonary veins and subsequent pulmonary edema.
•In truncus arteriosus, one major artery or “trunk” arises from the left and right ventricles in place of a separate aorta and pulmonary artery.
•In pulmonary stenosis there is an inability of the right ventricles to evacuate blood by way of the pulmonary artery. This obstruction may lead to right ventricular hypertrophy.