Echocardiographic assessment of interrupted aortic arch.

Background: In patients with interrupted aortic arch echocardiography provides detailed information about the anatomy of the aortic arch and the associated cardiac anomalies. Only a few reports have evaluated the reliability of this non-invasive diagnostic procedure by correlation with angiographic and surgical findings.

Methods: From 1988 through 1993, 45 infants with interrupted arch underwent surgical repair (mean age 13.02 days). Of the patients, 33 had interruption of the arch between the left common carotid and subclavian arteries; 25 patients had a ventricular septal defect, and the remaining 20 had coexisting complex congenital heart defects. Preoperative diagnosis was made exclusively by echocardiography in 25 of the patients. Accuracy of echocardiographic diagnosis was evaluated retrospectively by comparing preoperative studies with angiography and surgical reports. We then investigated whether the morphologic features of the interrupted arch might influence surgical procedure or outcome.

Results: Intracardiac anatomy was accurately diagnosed by echocardiography in all cases; in 2 patients angiography provided additional information concerning the morphology of the aortic arch. Operative notes described differences in morphology of the arch in 7 patients, but these did not influence the surgical procedure. Direct anastomosis of the interrupted segments was possible in 38 patients, and 36 patients underwent primary intracardiac repair. Echocardiographic measurements revealed that the diameter of the ascending aorta was related to the number of vessels originating from the proximal aortic arch. The distance between the interrupted segments was significantly different according to the site of interruption, but not between cases with an isolated ventricular septal defect versus those with complex heart disease. It did not influence the method of arch repair, nor was it related to recurrent or residual obstruction.

Conclusion: Preoperative echocardiography offers accurate and complete diagnosis in the critically ill neonate with interrupted aortic arch and associated intracardiac abnormalities.