Cardiovascular Imaging

Pulmonary valve atresia

cyanotic congenital anomaly in which there is no connection between the ventricle and the pulmonary artery. Blood supply to the lungs is through a patent ductus arteriosus and systemic to pulmonary artery collaterals. There are two distinct types: pulmonary atresia with ventricular septal defect (VSD), which is the extreme form of the tetralogy of Fallot, and pulmonary atresia with an intact ventricular septum. The valve annulus and proximal main pulmonary artery are hypoplastic. In the type with VSD, the central and peripheral pulmonary arteries are hypoplastic and malformed and there are prominent systemic to pulmonary arterial collaterals. With intact ventricular septum the central and peripheral pulmonary arteries are normal. Pulmonary atresia with an intact septum may be associated with a hypoplastic right ventricle and competent tricuspid valve or a normal to dilated right ventricle with incompetent tricuspid valve. With competent tricuspid valve egress of blood from the right ventricle is by retrograde filling of myocardial sinusoids and coronary arteries. The chest X-ray shows pulmonary oligaemia with normal heart size or pulmonary oligaemia with cardiomegaly depending upon the presence or absence of tricuspid regurgitation. Echocardiography demonstrates absence of pulmonary valve echoes and depicts the size of the right ventricle. It can also display the severity of tricuspid regurgitation. Cardiac angiography demonstrates: a blindly ending outlet of the right ventricle; size of the ventricle; severity of tricuspid regurgitation; and retrograde opacification of myocardial sinusoids and coronary arteries.

CBH