Coronary computed tomography angiography in children

Abstract

Imaging the coronary arteries of children, with their faster heart rates, small vessel size and common inability to lie still or breath-hold, has been a major challenge. With numerous advances in technology, CT examinations can now be performed quickly, often with children free-breathing and with much lower radiation doses than previously. This has led to increased use in children. Care must be taken with technique and choice of electrocardiogram (ECG)-gating technique to obtain adequate imaging for a diagnosis while keeping radiation dose as low as reasonably achievable (ALARA). In this paper, we discuss techniques and tips for CT imaging of the coronary arteries in children, including use of dual-source- and ultrawide-detector CT scanners.

Keywords: Anomaly; Children; Computed tomography; Congenital heart disease; Coronary arteries; Dual-source computed tomography; Heart.

Fig. 1

Anomalous origin of the left coronary artery in a 16-year-old boy with syncope. a Oblique reconstruction from CT angiography in aortic root plane shows anomalous origin of the left coronary artery from above the right sinus of Valsalva with interarterial course and likely intramural course (straight arrow). Right coronary artery origin is normal (curved arrow). P posterior. b Coronal oblique reconstruction from CT angiography demonstrates oblong shape of the left coronary artery (arrowhead), taller than wide, suggesting intramural course. c Three-dimensional (3-D) reconstruction image from CT angiography viewed from the anterior demonstrates coronary artery origins and proximal course, with the anomalous left coronary artery originating above the right sinus (arrow). The pulmonary artery and ascending aorta were removed for adequate coronary artery visualization. d Curved planar reformat from CT angiography shows horizontal lines indicating level for virtual fly-through image. e Intraluminal virtual fly-through image from CT angiogram viewed from inside the aorta looking right at the level shown in (d). The intraluminal image of the proximal left coronary artery demonstrates oblong shape (arrow) of the coronary artery proximally. f Curved planar reformatted image from CT angiography shows horizontal lines at the level of the virtual fly-though image further distally in the coronary artery. g Intraluminal virtual fly-through image from CT angiography viewed from inside the right coronary artery at the level shown in (f) in the more distal left coronary artery, where it regains its rounded shape (arrowhead)

Fig. 2

Tetralogy-of-Fallot-like double-outlet right ventricle with probable single coronary artery in a 1.5-month-old girl. a Axial oblique reconstruction from CT angiography in plane of aortic root shows a coronary artery originating from the left sinus with trifurcation: right coronary artery (arrow); left anterior descending artery (LAD; arrowhead); and prominent diagonal branch. b The diagonal branch is better visualized on three-dimensional reconstruction. Three-dimensional reconstruction from CT angiography viewed from the anterior left shows coronary artery origin and trifurcation with right coronary artery (straight arrow), LAD (arrowhead) and prominent diagonal branch (curved arrow). The circumflex artery originated separately (not shown)

Fig. 3

Anomalous left coronary artery from pulmonary artery (ALCAPA) in a 3-month-old girl with cardiac dysfunction and concern for coronary anomaly. a Axial oblique CT angiogram shows anomalous left coronary artery (arrowhead) originating from the pulmonary artery (asterisk). b Coronal oblique CT angiogram shows left coronary artery (arrow) originating from the pulmonary artery (asterisk), known as ALCAPA

Fig. 4

Kawasaki disease and right coronary artery aneurysms in an 8-year-old boy. a Curved planar reformat from CT angiography of the right coronary artery (RCA) demonstrates a smaller aneurysm proximally (arrow) and a large aneurysm with coarse calcifications distally (arrowhead). b Three-dimensional reconstruction from CT angiography viewed from the right anterior also demonstrates a proximal aneurysm (arrow) and distal aneurysm with calcifications (arrowhead). c Curved planar reformat from CT angiography on follow-up 6 years later at 14 years old demonstrates increased calcification peripherally in both aneurysms as well as new high-grade stenosis just proximal to the proximal aneurysm (arrow) and a nearly non-opacified coronary artery segment between the aneurysms (arrowhead). d Coronal oblique reconstruction from CT angiography demonstrates high-grade stenosis (arrowhead) and near occlusion of the artery between the aneurysms (arrow)

Fig. 5

Early postoperative imaging in a 10-year-old boy with Loeys–Dietz syndrome status post aortic root replacement. Echocardiography in the acute postoperative period showed a flared tricuspid valve with right coronary artery injury by retraction in the operating room and subsequent repair. a, b Orthogonal reconstruction of CT angiography in the plane of the aortic root (a) and three-dimensional reconstruction of CT angiogram viewed from the left (b) demonstrate abrupt cutoff of the right coronary artery at its origin (arrows). c Multiplanar reconstruction of the right coronary artery from CT angiography shows no opacification of proximal right coronary artery (arrow), with reconstitution of the vessel distally (arrowhead)

Fig. 6

Late postoperative imaging in an 8-year-old girl with a history of D-transposition of the great arteries and coarctation status post repair, imaged for routine evaluation. a, b Coronal (a) and sagittal oblique (b) reconstructions from CT angiography demonstrate decreased caliber of right coronary artery as it courses around the main pulmonary artery to the right atrioventricular groove (arrows). c Three-dimensional reconstruction from CT angiography, viewed from the anterior with the pulmonary artery and ascending aorta removed above the sinotubular junction, also demonstrates right coronary artery narrowing (arrow). This focal narrowing corresponded to an area of decreased myocardial perfusion in the right coronary artery distribution on subsequent stress cardiac MR (not shown). This was thought to be a result of mass effect from the pulmonary artery

Fig. 7

Coronary artery vasculopathy in a 17-year-old girl status post heart transplant. a Sagittal maximum-intensity projection CT angiogram shows significant tortuosity of the left anterior descending (LAD) artery (arrow) as well as tortuous branches thought to be secondary to coronary artery vasculopathy. b Three-dimensional reconstruction from CT angiography viewed from above shows tortuous mid and distal LAD artery (arrow)

Fig. 8

Lead compression of the coronary arteries in a 13-year-old girl with epicardial pacer leads. a Axial oblique maximum-intensity projection (MIP) CT angiogram shows deviation and compression of the left anterior descending artery in the interventricular groove by an epicardial lead (arrow). b Catheter angiography in the right anterior oblique projection of a contrast injection of the left anterior descending (LAD) artery also demonstrates deviation and compression of the LAD (arrow). c Sagittal oblique MIP CT angiogram of the right coronary artery shows compression by an epicardial lead (arrow). d This is also demonstrated on subsequent catheter angiography in the left lateral projection (arrow). e Curved planar reformatted CT angiogram of the left coronary artery and LAD artery following lead removal shows no significant sequela