Atrial septal defects in pediatric patients: noninvasive sizing with cardiovascular MR imaging.
OBJECTIVE
To evaluate phase-contrast magnetic resonance (MR) imaging for sizing of secundum atrial septal defects (ASDs) and inflow MR angiography for detection of associated venous anomalies in pediatric patients with inconclusive transthoracic echocardiographic (TTE) results.


METHODS
Sixty-five children (mean age, 5.4 years +/- 2.7 [SD]) with ASD and inconclusive TTE results underwent phase-contrast MR imaging. Defect size and rim distances measured on MR imaging sections obtained in the ASD plane and from the defect to the venae cavae, aortic root, and atrioventricular valves were compared with transesophageal echocardiographic (TEE) findings (n = 30) during transcatheter closure or surgical measurements (n = 40) by using Bland-Altman analysis. Inflow MR angiography was compared with invasive cine angiocardiography for detection of associated venous anomalies.


RESULTS
For ASD size, mean differences were less than 1 mm between MR imaging and TEE measurements (with upper and lower limits of agreement between 2.3 and -3.3 mm) and were between 1.2 and -1.6 mm between MR imaging and surgical measurements (with upper and lower limits of agreement between 4.7 and -5.2 mm). Septal rim measurements at MR imaging agreed fairly well with TEE and surgical results. Septal length was overestimated at MR imaging versus TEE (mean difference, 3.0 mm; upper and lower limits of agreement, between 8.0 and -2.8 mm), but MR imaging septal length measurements agreed with surgical results. Rim distance to coronary sinus was difficult to assess. MR imaging enabled referral of 25 of 30 patients for successful transcatheter closure; five patients were found to have too large defects after balloon sizing. Multiple ASDs and/or associated vascular anomalies in 17 of 65 patients were clearly identified at MR imaging, compared with results of TEE, surgery, and cardiac catheterization.


CONCLUSIONS
In children with ASD and inconclusive TTE results, MR imaging can enable determination of defect size, rim distances to adjacent structures, and venous connections.
Beerbaum
Philipp
P
Clinic for Congenital Heart Disease, North Rhine-Westfalia, Ruhr-University Bochum, Georgstrasse 11, D-32545 Bad Oeynhausen, Germany. pbeerbaum@hdz-nrw.de
Körperich
Hermann
H
Esdorn
Hermann
H
Blanz
Ute
U
Barth
Peter
P
Hartmann
Johannes
J
Gieseke
Jürgen
J
Meyer
Hans
H
D000293:Adolescent; D000704:Analysis of Variance; D002648:Child; D002675:Child, Preschool; D017023:Coronary Angiography; D005260:Female; D006344:Heart Septal Defects, Atrial / Q000473:pathology* / Q000601:surgery; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011446:Prospective Studies