Retrograde Flow in the Descending Thoracic Aorta
Magnetic Resonance Imaging of an Apicoaortic Conduit
A 55-year-old woman was admitted with congestive heart failure caused by severe aortic valve stenosis. Conventional aortic valve replacement could not be performed because of a porcelain aorta. Thus, via an anterolateral thoracotomy, a Hancock 20-mm prosthesis (Medtronic Inc., Minneapolis, Minn) was inserted into the apex of the left ventricle and connected to a Carbomedics Carbo-Seal 21-mm valved conduit (Sulzer Carbomedics Inc., Austin, Tex), which in turn was sewn onto the descending aorta in an end-to-side fashion (Figure and Movie I in the online-only Data Supplement).
Magnetic resonance (MR) imaging was performed to evaluate postoperative anatomy, function, and flow. Four-chamber (Figure, A, and Movie II in the online-only Data Supplement) and transverse (Figure, B, and Movie III in the online-only Data Supplement) cine MR imaging provided excellent delineation of the insertions and course of the apicoaortic conduit (asterisk). MR flow measurements revealed a sufficient combined stroke volume at rest (ascending aorta, 16 mL; conduit, 39 mL) and estimated the distribution of flow over the ascending aorta, descending aorta, and conduit (Figure, D). Cine MR imaging showed competitive flow in the aortic arch and retrograde flow in the descending aorta (Movie IV in the online-only Data Supplement).
The online-only Data Supplement is available with this article at http://circ.ahajournals.org/cgi/content/full/122/2/e12/DC1.