Comprehensive assessment of morphology and severity of atrial septal defects in adults by CT

• We evaluated the usefulness of cardiac CT for adult patients with secundum ASD.
• The Qp/Qs ratio assessed by cardiac CT was comparable with that by catheterization.
• The maximum mean size of the ASD is the same for cardiac CT and TEE.
• In rim length, there are no significant differences for the cardiac CT and TEE.
• Cardiac CT could find clinical use when managing ASD patients.

BackgroundCardiac CT is an excellent tool for evaluating the anatomy of a secundum atrial septal defect (ASD). However, a comprehensive assessment of its usefulness, including measurement of the pulmonary to systemic blood flow ratio in secundum ASD patients, has not been performed.ObjectiveTherefore, this study was designed to evaluate the usefulness of CT for assessing the hemodynamics of secundum ASD in adults compared with transesophageal echocardiography (TEE), transthoracic echocardiography, and invasive catheterization.MethodsFifty adult patients with secundum ASD were enrolled. Cardiac CT scans (128-slice multidetector CT instrument) were acquired. These were followed by 2-dimensional reconstruction of the secundum ASDs to determine the defect size, the rim length between the outer edge of the defect, and the pulmonary to systemic blood flow (Qp/Qs) ratio.ResultsThe maximum sizes of the secundum ASDs derived from CT and TEE studies were comparable (21.2 ± 8.0 vs 20.0 ± 7.3 mm; P = .41; r = 0.960; P < .001). The rim lengths for the aortic, mitral, and tricuspid valves; the inferior vena cava; and posterior atrium were also comparable between CT and TEE measurements. The mean Qp/Qs ratio that was derived from CT measurements was comparable with that found by invasive catheterization (2.3 ± 0.7 vs 2.3 ± 0.8; P = .73; r = 0.786; P < .001).ConclusionCardiac CT is feasible for assessing pathology and the severity of secundum ASD in adults.