Innovations in abdominal aneurysm repair

Abstract

The use of EVAR has steadily grown, increasing from 56% of all elective AAA repairs performed in the US Medicare population in 2005 to 77% by 2008. As EVAR has become widely accepted as a safe technique, a large variety of commercially available stent grafts have been introduced. Interestingly, no clear evidence supports one specific treatment regimen over another; due to this debate, specific practice patterns have been shown to vary between institutions. Not only is there disparity in the implementation of different graft types during surgery, but there is also variation in endovascular surgical techniques. Compared to femoral cutdown access, percutaneous access further minimizes invasiveness and has also been shown to have high technical success rates. So far, however, there has not yet been a large-scale study that is generalizable to all relevant patients and practices. Despite the minimally invasive treatment option, open surgery repair remains necessary in certain circumstances or in individual patients. Even further, extensive discussion continues about the optimal established open approach: transperitoneal or retroperitoneal. Data regarding the long-term efficacy of open treatment have remained conflicting, while randomized trials and observational studies have demonstrated lower perioperative morbidity and mortality with endovascular AAA treatment. The survival benefit of EVAR, however, is not sustained. Aneurysmal degeneration is not limited to the aorta: although less common, these problems have been known to exist in the iliac and renal arteries as well. Iliac artery aneurysms may appear in isolation, comprising approximately 2% of all abdominal aneurysms. Isolated iliac artery aneurysms are uncommon, frequently asymptomatic, and most often discovered incidentally. The majority of isolated iliac aneurysms (70%) occur in the common iliac artery, while 20% and 10% are found in the internal and external iliac arteries, respectively. With an estimated incidence between 0.1-0.3%, renal artery aneurysms have also proven to be another form of isolated abdominal aneurysms; Unlike iliac arteries, however, the indications for surgical intervention of renal artery aneurysms - whether by open or endovascular techniques - remain controversial. The technical success and safety of endovascular treatment for both isolated iliac- and isolated renal artery aneurysms have been demonstrated. However, at this stage, little is known about the impact of the minimally invasive endovascular therapy on mortality and outcomes over time.