Type I endoleak
Citation, DOI and article data
Type I endoleaks are a subgroup of endoleaks which occur at graft ends, often due to an inadequate seal.
They occur as a result of poor apposition between one of the attachment sites of a stent-graft and the native aortic or iliac artery wall. Blood can leak through this defect into the aneurysm sac.
They can be seen immediately after stent-graft deployment due to several reasons including
- incomplete dilation of the stent-graft
- aortic tortuosity
- steep aortic angulation
Delayed type I endoleaks may be related to changes in the configuration of the aorta as the aneurysm sac shrinks. These are considered high-pressure endoleaks, and there is a high risk of aneurysm sac rupture because of direct exposure of the aneurysm wall to aortic pressure.
- most common after repair of thoracic aortic aneurysms 4
Type I endoleaks can be subdivided into three further categories
- Ia: proximal
- Ib: distal
- Ic: iliac occluder
Type I endoleaks can be associated with measurable increases in aneurysm sac size.
Preferred imaging modality. Multiphased scanning is helpful. Unenhanced CT may show hyperattenuating acute hemorrhage within the aneurysm sac.
After contrast administration, a dense contrast collection is usually seen centrally within the sac and is often continuous with one of the attachment sites.
On Doppler sonography, a jet of flow may be seen originating from one of the attachment sites.
Treatment and prognosis
Type Ia leaks
Initial treatment can include balloon angioplasty of the proximal attachment site, aimed at remodeling the stent graft to achieve an adequate seal. If angioplasty is unsuccessful, balloon-expandable bare-metal stents such as Palmaz stents can be deployed over the affected attachment site to promote apposition of the proximal stent graft with the aortic wall.
In cases of undersized or poorly deployed endografts, covered extension cuffs can be used. These can be matched in size and material to the native endograft.
Some newer devices include EndoStaples and EndoAnchors which mechanically attach the proximal endograft with the aortic wall.
Type Ib leaks
Are usually considered easier to manage than Ia leaks, with numerous available iliac extender limbs, covered stents, and bare-metal stents to close the endoleak defect.
Despite advances in endovascular techniques, there are still cases that require surgical repair for definitive treatment.
- 1. Kudo T, Kuratani T, Shimamura K, Sakamoto T, Kin K, Masada K, Shijo T, Torikai K, Maeda K, Sawa Y. Type 1a endoleak following Zone 1 and Zone 2 thoracic endovascular aortic repair: effect of bird-beak configuration. (2017) European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery. 52 (4): 718-724. doi:10.1093/ejcts/ezx254 - Pubmed
- 2. Shen A, Ologun GO, Keller H, Sampson L. Natural History Of an Untreated Type 1 Endoleak: A Case Report. (2017) Cureus. 9 (7): e1507. doi:10.7759/cureus.1507 - Pubmed
- 3. Mustafa R. Bashir, Hector Ferral, Chad Jacobs, Walter McCarthy, Marshall Goldin. Endoleaks After Endovascular Abdominal Aortic Aneurysm Repair: Management Strategies According to CT Findings. (2012) American Journal of Roentgenology. 192 (4): W178-86. doi:10.2214/AJR.08.1593 - Pubmed
- 4. James Chen and S. William Stavropoulos, Management of Endoleaks, Semin Intervent Radiol. 2015 Sep; 32(3): 259–264. doi: 10.1055/s-0035-1556825
- 5. Jonathan L. Eliason, Gilbert R. Upchurch. Endovascular Abdominal Aortic Aneurysm Repair. (2008) Circulation. 117 (13): 1738. doi:10.1161/CIRCULATIONAHA.107.747923 - Pubmed