Cath Lab Digest

The new age of aortic surgery is one of minimally-invasive endovascular procedures where endograft devices are the dominant technological force. It was relatively early during these developments that the term “endoleak” was coined by White et al (Ref. 1) to denote the presence of persistent blood flow inside the aneurysm sac — but outside of the implanted endoluminal endograft device (Figure 1). In other words, they felt this was not a true “leak”, as there was no extravasation of contrast outside the aorta (“rupture”), but the presence of circulating blood and perhaps pressure inside the aneurysm (post treatment) from incomplete fixation at the proximal or distal neck (types Ia and Ib, respectively), or modular component disconnection or graft defect (type III), or from branch backflow (type II). Such observations had certainly been made prior to 1996, but it was they who developed a comprehensive classification and provided a clear understanding of the issues surrounding the persistence of intra-sac flow and, most significantly, the term “endoleak” that would become a widely used label from that day onward.

Usage of the term caught on rapidly and has been become a very frequently used word in the endovascular lingo. The current popularity and proliferation of CT angiography has made discovery of endoleaks all the more likely. It is most unfortunately (and completely unintentional) that what resonates the most in the minds of the majority of physicians (who are not aortic intervention specialists) is the leak component of the term, with the obvious implication of possible serious — if not fatal — hemorrhage. And this is so even when the contrast-enhanced CT scan is performed routinely or as a planned follow-up study on a completely asymptomatic patient!

It is not unusual for a vascular surgeon (such as myself) who has treated many patients with aortic aneurysms endovascularly over the years to receive a “panic” or “urgent” call, at times in the middle of the night, with the report from a radiologist or emergency room physician (and others) that one such patient was just found to have a leak on a CT angiogram (or ultrasound)… And I’m afraid this will not end anytime soon.

We are therefore left with a well-conceived new term that was coined nearly 15 years ago and that has proved quite useful to advance the field of endovascular aortic repair. The unintended consequence of injecting “fear” and sometimes a sense of urgency or panic… are clearly related to the leak portion of the term. In retrospect, we could have been wiser all those years ago (before totally embracing the new term) and anticipate the potential implications of attaching the word “leak” to anything that has to do with the aorta! But we weren’t.

Reference
1. White GH, Yu W, May J, et al. Endoleak as a complication of endoluminal grafting of abdominal aortic aneurysms: Classification, incidence, diagnosis, and management. J Endovasc Surg 1997;4:152–168.

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Dr. Frank J Criado is a Board-Certified Vascular Surgeon and Endovascular Specialist at the Union Memorial Hospital-MedStar Health in Baltimore, Maryland – USA.

Dr. Criado is widely acknowledged to be a pioneer in endovascular therapy, with a 20-year + interventional experience. He has contributed extensively to the literature with more than 100 peer-reviewed published articles – mostly on various vascular and endovascular subjects, and Editor-in-Chief of Vascular Disease Management (VDM). He has also been active in clinical research, with a major focus on aortic stent-graft and carotid interventions, and endovascular technologies in general. He was the National Principal Investigator (P.I.) for the Medtronic Talent AAA clinical trials in the U.S., and a member of the Executive Committee for the Medtronic Valor Thoracic trial.

He is a founding member and immediate past President of the International Society of Endovascular Specialists (ISES), founder and current President of the endovascular surgery society of Latinamerica (CELA), and a member of all major U.S. and international vascular and endovascular societies. He is a Fellow of the American College of Surgeons (FACS) and of the Society of Vascular Medicine (FSVM), and a member of the Board of Directors of the Society for Vascular Surgery (SVS).