Computed tomography in congenital heart disease: how generic principles can be applied to create bespoke protocols in the Fontan circuit

Abstract

Cardiac computed tomography (CCT) has become an invaluable cross-sectional imaging modality in congenital heart disease (CHD) patients. However, altered anatomical connections and cardiovascular physiology makes CHD arguably the most challenging area in CCT imaging, which remains a complimentary modality to cardiac magnetic resonance and echocardiography. A bespoke CT protocol is often required to achieve a diagnostic examination; this can be achieved through careful consideration of the basic principles of image acquisition and contrast administration. This article reviews these principles and demonstrates how they can be applied to CCT in CHD using the Fontan circulation as an example.

3D printing in medicine: current applications and future directions

“…Technical developments in medical imaging techniques have led to significant improvements in the diagnostic performance of less-invasive imaging modalities such as computed tomography (CT), magnetic resonance imaging (MRI), nuclear medicine and ultrasound. Quantitative analysis of these imaging modalities allows for detection and diagnosis of various diseases with high accuracy (1)(2)(3)(4)(5)(6)(7)(8)(9)(10). Despite promising results available in the literature, traditional two-dimensional (2D) and three-dimensional (3D) visualization tools are still limited to a 2D screen, which affect realistic visualization of anatomical structures and pathologies of 3D datasets, and this is particularly apparent when dealing with complex pathologies.…”

Optimal CT Contrast Enhancement Protocol for the Fontan Pathway: An Analysis Based on a 15-year Single-center Experience

“…One way of increasing the CNR is by using a shorter scan delay, but the 60-second delay seemed to lead to inhomogeneous enhancement in the Fontan pathway based on the results of this study. Some researchers suggested a 70-second delay [1,12] and others suggested an 80-100 second delay [10]. However, it should be carefully considered that heterogeneity of contrast enhancement in the Fontan pathway seems to be increased proportional to the shortening of the scan delay.…”

“…The typical contrast enhancement protocols used to evaluate congenital heart disease almost always result in non-uniform, non-diagnostic contrast enhancement on cardiothoracic CT; therefore, additional delayed scanning is often required in patients with the Fontan pathway. Consequently, several contrast enhancement protocols dedicated to evaluate the Fontan pathway on cardiothoracic CT have been suggested [6][7][8][9][10][11][12]. An expert consensus document recommended a venous two-phase or split injection method, in which 30-50% of the contrast agent is given and followed by a 30-60 seconds pause and then by the second injection of contrast agent [13].…”

Non-invasive Imaging in the Evaluation of Cardiac Shunts for Interventional Closure

“…These sources of shunt can be detrimental to the patient and addressed by transcatheter occlusion (54). Identification and quantification of these shunts can be challenging by echocardiography, and CT is very challenging in a Fontan circulation due to the passive flow and inherent delays in systemic venous return particularly in the inferior limbs of the circulation (55). Agitated saline contrast echocardiograms can help screen for the presence of significant right-to-left shunts.…”