Echocardiographic Evaluation Before Bidirectional Glenn Operation in Functional Single-Ventricle Heart Disease: Comparison to Catheter Angiography

Cardiac catheterization is routinely performed in patients with single ventricle before bidirectional Glenn operation (BDG). There is interest in noninvasive evaluation alone before BDG, but concern for echocardiography successfully imaging the relevant anatomy persists. We evaluated the accuracy of echocardiographic imaging of vascular anatomy. Diagnostic images of 130 patients who had echocardiography and catheterization before BDG were reviewed; diameters of the pulmonary arteries (PAs) and aortic arch were measured, and stenoses were recorded. Patient and procedural factors associated with echocardiographic imaging were analyzed. Median age at echocardiography was 4 months; the most common diagnosis was hypoplastic left heart syndrome (55%). The left PA was imaged by echocardiography in 83 patients (64%), with 4 of 21 stenoses (19%) diagnosed by catheterization identified; similarly, the right PA was imaged in 81 (62%), and 3 of 17 stenoses (18%) were identified. The distal aortic arch was visualized in 104 (80%), with successful identification of 21 of 27 (78%) of coarctations diagnosed by catheterization. Complete vascular echocardiography (visualization of PAs and aortic arch) occurred in 43% and was not obtained more frequently with sedation. In a large cohort of patients presenting for BDG, evaluation by echocardiography frequently failed to image the PAs and missed the majority of PA stenoses. Sedation did not appear to improve the performance of echocardiography for evaluation of the PAs. Echocardiography cannot be relied on as the sole investigation before BDG.