Left atrial appendage clot
68 yo M with h/o mitral stenosis, atrial fibrillation and poor medical compliance presents with acute onset of bilateral leg pain. On exam, both feet were pulse-less. CTA confirmed bilateral popliteal artery occlusion, with an acute appearance.
Images from the lower chest obtained as part of CTA show enlarged left atrium. Conventional CT image shows layering low density material in the left atrial appendage. On spectral analysis, this is consistent with clot, showing no iodine uptake.