Congenital Thoracic Vascular Anomalies: Evaluation with State-of-the-Art MR Imaging and MDCT

Congenital Thoracic Venous Anomalies in Adults: Morphologic MR Imaging

“…3 Both black-blood and bright-blood images can be obtained without intravenous administration of contrast material. Blackblood images (typically acquired with single-shot fast spin echo with double inversion recovery or half-Fourier single-shot turbo spin echo sequences) are useful to study the anatomy of the heart and mediastinum; cine bright-blood images (usually obtained using a 2-dimentional (2D) or 3D balanced steady-state free precession sequence) allow the assessment of the cardiac chambers and valvular function.…”

“…Blackblood images (typically acquired with single-shot fast spin echo with double inversion recovery or half-Fourier single-shot turbo spin echo sequences) are useful to study the anatomy of the heart and mediastinum; cine bright-blood images (usually obtained using a 2-dimentional (2D) or 3D balanced steady-state free precession sequence) allow the assessment of the cardiac chambers and valvular function. 3,4 Angiographic techniques include 3D T1-weighted contrastenhanced MRA, time of flight MRA, and phase contrast MRA, the latter 2 providing angiographic information in patients in whom intravenous administration of gadolinium is contraindicated. Gadolinium-enhanced MRA (non-electrocardiogram-gated 3D spoiled gradient recalled echo imaging technique) is extremely valuable in the assessment of the thoracic vascular structures, allowing dynamic imaging during the arterial and venous phases, of both the systemic and pulmonary circulation.…”

“…Phase contrast MRA, also called velocity-encoded sequence, evaluates flow direction and velocity, allowing the quantification of shunts. [2][3][4] Our standard protocol for evaluating thoracic venous anomalies consists of axial, sagittal, and coronal half-Fourier single-shot turbo spin echo sequences, steady-state free precession sequences to evaluate ventricular function, and 3D contrast-enhanced MRA. Contrast-enhanced MRA image is obtained after intravenous injection of a double dose (0.20 mmol/kg of body weight) of gadolinium-containing contrast media, at an injection rate of 2 mL/s; the acquisition is initiated manually using care bolus tracking technique.…”

“…9 In the remaining cases, involution of the right common cardinal vein and the central anterior cardinal vein, along with persistence of the left anterior cardinal vein and of the anastomosis between the right and left cardinal veins, results in absence of the right SVC with a mirror image of the thoracic systemic venous drainage (Fig 4). 3 In most patients (92%), the LSVC drains into the right atrium through the coronary sinus, which enlarges to accommodate the blood flow (Figs 4, 5). 7,9 Enlargement of the coronary sinus may potentially lead to left atrioventricular valve inflow obstruction, and subsequently to cardiac arrhythmias or sudden death.…”

“…7,9 Enlargement of the coronary sinus may potentially lead to left atrioventricular valve inflow obstruction, and subsequently to cardiac arrhythmias or sudden death. 3 In the remaining cases, the LSVC terminates in the left atrium, resulting in a right to left shunt. 7 The risk of congenital heart disease in such patients is considerably increased.…”