- An aneurysm is a pathological dilation of a section of vasculature or heart. A variety of clinically important aneurysmal subtypes are discussed below distinguished by their anatomical location or pathogenic mechanism.
- True vs Pseudo
- True Aneurysms are bounded by all three layers of the blood vessel, meaning the tunica, media, adventitia
- Psuedo-Aneurysms are generated when blood dissects into the vascular wall itself and may be bounded only by the tunica adventitia or by a perivascular thrombus
- Fusiform vs Saccular
- Fusiform aneurysms appear as symmetric dilations of the blood vessel
- Saccular aneurysms arise from focal defects of the vessel wall and thus manifest as local outpouchings