Anomalous Origin of One Pulmonary Artery Branch From the Aorta: Role of MDCT Angiography.

OBJECTIVE

The purpose of this study was to evaluate the prevalence, MDCT angiography (MDCTA) appearance, associated congenital cardiovascular abnormalities, and prognosis of anomalous origin of one pulmonary artery from the aorta (AOPA) on the basis of MDCTA.

MATERIALS AND METHODS

We conducted a retrospective search of patients with AOPA from our database in a single center, consisting of 5729 patients referred for MDCTA with known or suspected congenital heart diseases from transthoracic echocardiography. The clinical information, subtypes of AOPA, associated cardiovascular anomalies, and surgical and clinical outcomes were retrospectively collected and analyzed. The MDCTA images were retrospectively processed for analysis, and the MDCTA and echocardiography images were interpreted by radiologist and cardiologist without knowledge of the actual diagnosis or surgical outcome.

RESULTS

AOPA was seen in 19 patients (14 males and five females; median age, 3 months; range, 4 days-21 years) showing a prevalence of 0.33%. Anomalous origin of the right pulmonary artery (AORPA, 89%), proximal origin subtype of the AOPA (89%), and ipsilateral aortic wall origin of AOPA (58%) were more commonly seen. In addition to the benefit of preoperative planning, MDCTA also supplemented echocardiography by providing accurate diagnosis of AOPA and other associated cardiovascular anomalies compared with transthoracic echocardiography (TTE). We found a total of four patients (21%) with misdiagnosis by TTE, including three patients with underdiagnosis of AOPA and one patient with misdiagnosis as transposition of the great arteries. In addition, two other patients had AOPA diagnosed, but the associated patent ductus arteriosus (PDA) was not detected. MDCTA revealed 95% association with other congenital cardiovascular anomalies, including PDA (71% of AORPA), and aortic arch anomalies (100% of anomalous origin of the left pulmonary artery, AOLPA). The types of surgery depended on the MDCTA findings, including the sub-type, origin sites of AOPA, and associated cardiovascular anomalies. Analysis of the pulmonary arterial sizes showed the McGoon ratios in these patients with a median value of 2.4 (range, 1.5-2.9). Surgical treatment performed before the age of 1 year enabled normalization of pulmonary artery pressure in 92% of patients.

CONCLUSION

AOPA had a prevalence of 0.33% among patients with congenital heart disease in our series. MDCTA was an important supplement for the diagnosis, delineating the different subtypes and origin sites of AOPA and permitting preoperative planning of AOPA in patients suspected on the basis of echocardiography of having AOPA because accurate diagnosis and early surgical treatment remain the mainstays in improving patient outcome.