A 51-year-old man with a ruptured pancreaticoduodenal artery (PDA) aneurysm caused by compression of the celiac artery by the median arcuate ligament and aortic dissection involving the celiac axis was transferred to our hospital for endovascular treatment. A 4-F catheter was advanced into the superior mesenteric artery through the narrow true lumen via the left brachial artery, and coil embolization of the aneurysm was successfully performed. In this case, rapid increase of blood flow in the superior mesenteric artery, which compensated for the decreased celiac blood flow by aortic dissection, increased hemodynamic stress on the PDA, leading to aneurysmal rupture.