Which endoleak type is described as a leak at the graft attachment site?

Which endoleak type is described as a leak at the graft attachment site?

• A. Type II
• B. Type I
• C. Type III
• D. Type IV

Answer: (B)

A leak at the graft attachment site is a Type I endoleak. This occurs when the seal at the proximal or distal end of the stent graft fails, allowing high-pressure arterial blood to flow directly into the aneurysm sac. Because the leak is at the graft’s attachments, the sac remains pressurized and rupture risk stays high, so this is the most urgent type to address. In contrast, a Type II endoleak comes from retrograde flow into the sac through branch vessels (like lumbar arteries or the inferior mesenteric artery) and is typically lower pressure, sometimes monitored or treated if it enlarges the sac. Type III endoleak results from defects in the graft fabric or a separation of modular components, also a high-pressure source but due to the graft itself rather than the attachment seal. Type IV endoleak is from porosity of the graft material, usually early and often self-limiting.

A leak at the graft attachment site is a Type I endoleak. This occurs when the seal at the proximal or distal end of the stent graft fails, allowing high-pressure arterial blood to flow directly into the aneurysm sac. Because the leak is at the graft’s attachments, the sac remains pressurized and rupture risk stays high, so this is the most urgent type to address.

In contrast, a Type II endoleak comes from retrograde flow into the sac through branch vessels (like lumbar arteries or the inferior mesenteric artery) and is typically lower pressure, sometimes monitored or treated if it enlarges the sac. Type III endoleak results from defects in the graft fabric or a separation of modular components, also a high-pressure source but due to the graft itself rather than the attachment seal. Type IV endoleak is from porosity of the graft material, usually early and often self-limiting.