Evaluation of radioisotopic angiocardiography in patent ductus arteriosus

Dynamic images and curves obtained from radioisotopic angiocardiography (RI-ACG) using video recording system were studied in 5 patients with patent ductus arteriosus (PDA), to disclose any characteristic findings of PDA on this radioisotopic examination. And, the examination was evaluated with referance to diagnosis and assessment of status of PDA, comparing with other radiological examinations including angiocardiography and catheterization. Both the dynamic images and the dynamic curves of RI-ACG showed some characteristic findings of PDA, which was considered to be valuable to differentiate the intracardiac left to right shunt in atrial or ventricular septal defect. It was very characteristic of PDA that dynamic images showed regional dilution and recirculation patterns in the region of the main pulmonary artery to its periphery, and dynamic curves presented shunt waves on the descending limbs of the first circulation waves of both the pulmonary and the left ventricular region of interest. The Degrees of appearance of these characteristic findings showed a tendency to well correlate with the value of the left to right shunt fraction calculated by cathetelization technique. On the other hand, RI-ACG showed useful findings to diagnose pulmonary hypertension or heart failure associated with PDA. And, RI-ACG was very useful to detect an abrupt change of the central circulation dynamics in a patient with PDA, in whom continuous murmur characteristic of PDA desappeared intermittently. (author)