Computed tomography angiography with three-dimensional reconstruction for pulmony venous definition in high-risk infants with congenital heart disease

Abstract

Background: Pulmonary venous anomalies may be difficult to define in small, critically ill infants using standard echocardiography. In many centers, invasive cardiac catheterization is used if the diagnosis remains inconclusive. We evaluated computed tomography angiography (CTA) as a low-risk alternative to cardiac catheterization in these infants.

Methods: All infants <7 kg with congenital heart disease who had undergone CTA in a tertiary care pediatric institution during a 30-month period were included. All had undergone preceding echocardiography, with pulmonary veins defined as normal (group A, n = 40), or abnormal (group B, n = 16). In 6 group B patients, a conclusive diagnosis could not be made by echocardiogram alone. CTAs were analyzed only if contrast density in the left atrium exceeded 200 Houndsfield units. CTA diagnoses (using axial and reformatted 3-dimensional still frame images, and audio video interleaved loops) were compared with preceding echocardiograms (group A), or echocardiography, catheterization angiography, or surgical findings (group B).

Results: Fifty-six patients (mean age 12.4 weeks; range 0-64; mean weight 4.19 kg; range 1.4-7) were included. There were no scan complications. Mean scan duration was 4.6 seconds (range 1.84-11). Scan indications in group A were related mainly to arch (57.5%) and airway issues (17.5%). In group B, most patients had variations of anomalous pulmonary venous return (43.75%), with postsurgical stenosis the second largest group (31.25%). CTA diagnoses were confirmed in all patients. Additional diagnostic confirmation in group B was made at catheterization (1/16) or during surgical intervention (15/16).

Conclusion: Normal and abnormal pulmonary veins could be defined accurately, safely, and rapidly by CTA in all cases. Three-dimensional reformatting provided additional assistance with surgical planning. Echocardiography remains the first-line choice for diagnostic imaging in all patients with pulmonary venous anomalies. However, when echo diagnosis is inconclusive, CTA and not catheterization should be considered the next imaging modality of choice.