Is aortic aneurysm same as aortic dissection?

No. An aortic dissection is a tear in the lining of the aorta, causing blood to leak into the aortic wall, causing pain and possibly hemodynamic issues. An aneurysm is an enlargement of the vessel to more than 2 times its normal size. Dissections may occur in aneurysms, and may become aneurysmal, but can occur independent of each other.