Assessment of post‐atrial switch baffle integrity using a modified dual extremity injection cardiac computed tomography angiography technique

Abstract

Current standard practice for ECG (electrocardiogram)-gated CT (computed tomographic) angiography of the heart involves injection from an upper extremity vein into the superior vena cava (SVC). Noncontrast bloodmixing from the inferior vena cava (IVC) and high density of contrast injected through the SVC frequently produces artifacts that obscure anatomical detail of the right heart, particularly the right atrium. Thismakes detailed assessment of the right atriumandcavoatrial junction difficult especially in complicated situations such as surgically corrected congenital cardiac malformations. In our institution we adopted a modified injection protocol using dual extremity contrast injections which provide artifact-free images of the right heart. Two examples of this technique for patients with post‐Mustard operation for transposition of great arteries (TGA) are shown to evaluate the anatomy of the heart including the right atrium, the cavoatrial junction and the atrial baffle. Both studies showed complimentary information to that obtained with echocardiography. The dual injection techniquehas beenused for Fontan shunts using a different approach with some limitations compared to our technique [1]. Using our technique, a 20-gauge angiocatheter needle was inserted into the antecubital vein and a second needle (similar size but longer in