Type II endoleaks are the most common, and least serious type of endoleak.

An endoleak is a leak into the aneurysm sac after endovascular repair.

By contrast, the development of an endoleak from degeneration of endograft fabric would be a device-related complication.

After a mean follow-up of 13.8 months there were no endoleaks detected on postoperative CT scan follow-up, however one patient has had persistent aneurysm growth despite the absence of demonstrable endoleak.

Along with a short proximal aortic neck, necks with any of these characteristics are called "hostile necks" and endovascular repair can be either contraindicated or associated with early late complications of endoleak, or endograft migration, or both.

Standard EVAR is appropriate for aneurysms that begin below the renal arteries, where there exists an adequate length of normal aorta (the "proximal aortic neck") for reliable attachment of the endograft without leakage of blood around the device ("endoleak").