endoleak
Persistent blood flow into aneurysm sac following endovascular repair, classified by anatomical source.
Full Definition
An endoleak is persistent blood flow into an aneurysm sac following endovascular aneurysm repair (EVAR), representing failure of complete aneurysm exclusion from systemic circulation. Endoleaks are classified into five types based on their anatomical source and mechanism: Type I (attachment site leaks), Type II (branch vessel backbleeding), Type III (device-related defects), Type IV (fabric porosity), and Type V (endotension without visible leak). Type I and III endoleaks are considered high-pressure leaks requiring immediate intervention due to continued aneurysm pressurization and rupture risk. Type II endoleaks are low-pressure and may be observed if the aneurysm sac remains stable. Detection relies on contrast-enhanced CT angiography, and treatment options include transcatheter embolization, surgical conversion, or additional endograft components depending on the leak type and anatomy.
Usage
Usage note: Classification system (Type I-V) should be capitalized
In Context
- "A Type II endoleak was identified on the six-month surveillance CT following EVAR." — Post-operative imaging report
- "The Type I endoleak required immediate treatment with a proximal cuff extension." — Endovascular revision procedure note