Detection of pulmonary and coronary artery anomalies in tetralogy of Fallot using non-ECG-gated CT angiography

Abstract

Objectives: To evaluate the use of non-ECG-gated computed tomography (CT) angiography to describe pulmonary and coronary defects in patients with tetralogy of Fallot (TOF).

Patients and methods: This retrospective study was carried out on TOF patients having undergone pre-operative non-ECG-gated CT angiography between February 2007 and September 2012. The following clinical parameters were recorded: mean age at CT angiography, sex, the existence of genetic disease and the need to sedate the patient prior to CT angiography. CT data were analyzed retrospectively to determine the site(s) of pulmonary stenosis (infundibular, valvular or arterial), the size of pulmonary arteries and the presence of anomalous coronary artery courses. CT findings were then compared to the anatomy observed during surgery.

Results: Thirty-five patients were included in the study. The mean age was 4.30±1.91months (boys/girls=17/18). Two patients had associated chromosome disorders (one 22q11 microdeletion and one CHARGE syndrome). Sixteen patients (45.71%) were sedated prior to CT. Pulmonary artery assessment revealed 24 patients (68.57%) with infundibular stenosis, 5 (17.5%) with infundibular and/or valvular stenosis, and 6 (21%) with anomalous pulmonary arteries. CT angiography also evidenced anomalous coronary arteries in 8 patients (22.85%).

Conclusion: Due to its reduced scanning time and high spatial resolution, non-ECG-gated CT angiography is a non-invasive imaging modality that provides accurate information on pulmonary and coronary artery anatomy in patients with TOF.

Keywords: Computed tomography; Coronary artery; Pulmonary artery; Tetralogy of Fallot.