Cardiovascular imaging approach in pre and postoperative tetralogy of Fallot

Fig. 1. Diagram of the anatomy in Tetralogy of Fallot (Image reproduced with permission from Medscape Drugs & Diseases (https://emedicine.medscape.com/article/2035949-overview 2018)

Fig. 2. Chest radiograph of child with TOF showing the classical “boot-shaped heart” due to the narrow mediastinum and RV hypertrophy with decreased pulmonary vascular markings

Fig. 3. Echocardiography in postoperative TOF. a Parasternal short axis view of pulmonary valve (crosses), right ventricular outflow tract (arrow), main and branch pulmonary arteries. b Turbulence along stenotic pulmonary valve of an RV to pulmonary artery conduit without stenosis in the RV outflow tract. c Doppler tracing along the stenotic conduit indicates severe stenosis with maximal pressure gradient 98 mmHg

Fig. 4. CMR in TOF. a CMR angiography showing mirror-image right aortic arch, anatomy of the pulmonary branches and supply of both pulmonary arteries by bilateral modified Blalock-Taussig shunts (arrows), without connection of the left pulmonary to the main pulmonary artery. b CMR white-blood cine frame in the short axis plane shows a dilated, hypertrophic RV compressing the LV and the very stenotic, threadlike conduit from the RV to the pulmonary artery (arrow)

Fig. 5. CMR flow and volume measurements in repaired TOF used to evaluate PR. a Flow measurements in the main pulmonary artery indicate increased antegrade flow in systole (68.5 ml) with significant retrograde flow in diastole (36.9 ml) also depicted in the upper left flow diagram, calculating a PR fraction of 46%. b Volume measurements of the RV and LV show significantly increased RV stroke volume compared to the LV due to the severe PR. Both flow and planimetry derived RV forward volumes during systole coincide due to absence of significant tricuspid regurgitation

Fig. 6. CMR in repaired TOF showing late gadolinium enhancement in the RV outflow tract (green arrows). Of note, late gadolinium enhancement at the hinge points of the ventricular wall to the septum (red arrows) is common and nonspecific in TOF

Fig. 7. CCT in postoperative TOF showing dilated RV with bowing of the ventricular septum towards the LV, the surgical ventricular patch (black arrow) and a significant residual ventricular septal defect (white arrow). LV, left ventricle; RV, right ventricle

Fig. 8. CCA in unrepaired TOF. a Right anterior oblique projection and b lateral projection of RV ventriculogram showing the hypertrophic RV ejecting most of the contrast to the overriding aorta, as well as the severe RV outflow tract obstruction (arrow) below the stenotic pulmonary valve

Fig. 9. CCA in repaired TOF. a Lateral projection of injection in the right pulmonary artery showing severe PR with opacification of the whole RV cavity. b Left coronary angiography (white arrow) simultaneously with balloon interrogation in the bioprosthetic pulmonary valve to delineate the coronary origin prior to percutaneous pulmonary valve implantation. Note the atrial septal defect occluder (black arrow). PA, pulmonary artery; RV, right ventricle