Noninvasive evaluation of single-ventricle patients before Fontan operation

Abstract

Objective To determine whether patients with single-ventricle physiology who are free from known risk factors could skip routine pre-Fontan hemodynamic evaluation, without affecting the postoperative outcome. Methods A diagnostic algorithm including echocardiographic, clinical, and angiographic risk factors was used retrospectively to evaluate all 44 patients who underwent Fontan completion at Hamad General Hospital between January 2000 and December 2012. We evaluated the efficacy of this algorithm as a screening tool to identify inoperable and high-risk patients in whom pre-Fontan cardiac catheterization should be performed. Results Mean age at Fontan completion was 5.9 years (range 1.08–24.5 years), and mean weight was 18 kg (range 7.4–60 kg). Three patients were found to be inoperable based on hemodynamic cardiac catheterization results. The algorithm was highly sensitive in detecting all 3 inoperable patients who were classified as high-risk subjects. Of the other 41 patients, 17 (41%) had no risk factors and 24 (59%) had one or more risk factors. This noninvasive algorithm showed a sensitivity of 83% and specificity of 76% in detecting adverse postoperative outcomes. The sensitivity did not change after adding hemodynamic data obtained by cardiac catheterization as additional risk factors. Conclusion This noninvasive diagnostic algorithm could be used as an effective screening tool to detect patients in whom pre-Fontan cardiac catheterization could be avoided; magnetic resonance imaging and computed tomography can be a good substitute.