Table 3 Summary of complications by anatomical review area and repaired complex ACHD type

Heart

Heart failure

Repaired TOF

Right heart failure due to pulmonary valve insufficiency/RVOT obstruction

RV and IVC dilatation

Septal flattening

Repaired D-TGA

Right heart failure and tricuspid regurgitation due to opposing the systemic circulation (atrial switch)

SSFP cine MRI sequences assess structure and function

Fontan circuit

Right heart failure due to high resistance in the Fontan circuit

MRI late gadolinium enhancement in fibrosis/infarction

Coronary arteries

Coronary stenosis

Repaired D-TGA

Ostial stenosis after coronary translocation (arterial switch)

Ostial stenosis on CT coronary angiogram

3D SSFP/contrast angiography on MRI demonstrates ostial stenosis

Valves

Infective endocarditis

All conditions

Endothelial and valvular disruption due to altered flow haemodynamics

Filling defects, septic emboli

Vegetations can be low-to-intermediate signal on MRI

Aorta

Aortic dilatation

All conditions

Multifactorial. Progressive medial degeneration in complex ACHD

Dilated ascending aorta (normal values vary per patient)

Pulmonary vessels

Pulmonary hypertension

All conditions

Volume overload due to a residual shunt. High resistance in Fontan circuit

Dilated pulmonary arteries, peripheral pruning

Collaterals, AVMs

Fontan circuit

Increased pathway resistance

Contrast CT/MRI or 3D SSFP MRI to detect dilated tortuous vessels

Airway and lungs

Airway obstruction

All conditions

Extrinsic compression caused by dilated vessels, and/or cardiomegaly

Direct signs of airway stenosis on CT/MRI. Hyperinflated lungs

Plastic bronchitis

Fontan circuit

Abnormal lymphatic flow results in bronchial cast formation

Bronchial intraluminal opacities, groundglass lung changes on CT

Post-surgical complications and neo-pathways

All conditions

Thrombosis. Multiple factors. Atrial arrhythmia is a known cause

Filling defects. Hypointense on MRI during early enhancement

Repaired TOF

Residual RVOT obstruction, conduit stenosis, pulmonary artery stenosis

Contrast-enhanced CT for direct visualisation of stenosis

Repaired D-TGA

Baffle stenosis/leaks (atrial switch)

Supravalvular/branch pulmonary artery stenosis (arterial switch)

Conduit stenosis (Rastelli)

MRI: SSFP cine, 3D SSFP, and contrast angiography can all detect areas of stenosis or leak

Fontan circuit

Intra-atrial baffle or extra-cardiac conduit stenosis

PC MRI to quantify flow or magnitude of leak