[Evaluation of pulmonary arteries using nuclear magnetic resonance in patients with pulmonary atresia].

OBJECTIVES

Patients with pulmonary atresia and a ventricular septal defect have one outlet vessel; the aorta. The pulmonary arteries may be present or absent, and there is a collateral shunt. Magnetic resonance imaging is used to study this.

MATERIAL AND METHODS

We evaluated 10 patients with pulmonary atresia with ventricular septal defect. Five were males and the others were females, ages ranged between 1 day and 25 years, three patients were newborns. We used common planes, but mainly: axial-transverse and coronal, normal and right or left oblique projections.

RESULTS

The size of the ventricular septal defect was 1.75 +/- 0.67 cm (0.5-3.2). The pulmonary trunk was absent in 7 patients, it was atretic in 2 and it was present in one. Confluent pulmonary branches were seen in 6 patients (right 0.58 +/- 0.12, left 0.53 +/- 0.19), not confluent in 2 (with only one branch in each case) and absent in the other two. There was collateral shunt flowing from the descending aorta in 7 patients, from the ascending aorta in two and from the aortic in the final case. The ascending aorta was dilated in all cases (diameter 3.04 +/- 1.39), afterwards the relation between the ascending aorta and the descending aorta was 1.87 +/- 0.25. The aortic arch was right sided in 5 patients.

CONCLUSIONS

Magnetic resonance imaging is an alternative diagnostic method to angiocardiography. It gives complete information about the size, the position and the connection of the pulmonary arteries. It is also useful to evaluate the aortopulmonary to bronchial shunt.