Echocardiographic detection of intimo-intimal intussusception in a patient with acute Stanford type A aortic dissection.

Intimo-intimal intussusception is a very rare and unusual complication of type A dissections, typically noted on TEE exam. It has been reported in a few cases in the cardiothoracic surgical and radiology literature, and even more rarely in the cardiac anesthesia/TEE literature. This uncommon variation occurs in severe, acute, type A dissections when the ascending aortic intima circumferentially strips and detaches from the media and forms a tube-like structure which may either prolapse antegrade into the ascending aortic lumen or retrograde into the left ventricular (LV) outflow tract and LV cavity. Antegrade intussusceptions may be severe enough to partially or completely occlude the ostia of the innominate, left common carotid, and left subclavian arteries producing acute neurologic symptoms. Retrograde intussusceptions may severely impair LV filling in diastole, can worsen aortic insufficiency, mitral regurgitation, as well as produce occlusion of the coronary ostia and acute coronary ischemia. Here, we describe the incidental finding of a retrograde intussusception that was not visualized on computed tomography scan but by intraoperative TEE examination, in a patient with a severe, extensive type A dissection.