Pseudoaneurysm after surgical repair. ECG-triggered volumetric contrast-enhanced cardiac CT (AquilionONE, Toshiba medical systems) acquired during systole within a single heart beat at a heart rate of 109 beats per minute, in 2 years female patient. Image in transverse orientation. Large precardiac contrast collection (CC) with open connection (two-sided arrow) to the right ventricle (RV), at the site of RV patch (P). CT differential diagnosis was RV patch aneurysm or pseudoaneurysm. Surgery confirmed pseudoaneurysm. Dose-length product of the CT scan was 18.2 mGy·cm. Correction factor for chest CT at 100 kV for 2 years age was 0.044 mSv·mGy−1·cm−1; effective dose E was 1.4 mSv.