Krassi Ivancev

Purpose: To study factors that might contribute to intraoperative proximal type I endoleak and to evaluate the placement of giant Palmaz stents as a therapeutic option. Methods: Thirty-three patients (30 men; median age 72 years, range 50–85) with abdominal aortic aneurysms underwent implantation of fully supported Gianturco Z-stent—based endografts (12 custom-made aortomonoiliac and 21 bifurcated Zenith devices). Ten (30%) patients were treated for intraoperative proximal endoleaks. Stent-graft oversizing and neck angulation, length, and shape were compared between patients with and without leaks. Results: In 9 cases, the endoleaks were successfully treated with intraoperative placement of Palmaz stents without complications. In 1 patient, a leak that was resolved intraoperatively with balloon dilation reappeared 1 month later; a Palmaz stent was deployed successfully. Stent-graft oversizing did not differ significantly between patients who developed proximal endoleaks and those who did not (median 4.0 mm in both groups, p = 0.47). Median neck length was 21.0 mm in patients with endoleak and 28.0 mm in those without (p > 0.99). Median neck angulation was 30° in both groups (p = 0.33), and the presence of a conical aneurysm neck was not significantly different (2/10 versus 6/23, p > 0.99). All aneurysms remained excluded at a median follow-up of 13 months (range 6–24). Conclusions: Stent-graft oversizing and neck morphology (length, angulation, and conical shape) do not seem to correlate with the incidence of proximal type I endoleaks. Palmaz stent placement appears to be a feasible and safe treatment option for this complication.

To analyze the morphology of abdominal aortic aneurysms (AAAs) and to study the usefulness of spiral computed tomography (CT) versus digital subtraction angiography (DSA) in the evaluation of patients for endovascular repair. Of 133 AAA patients (120 men, mean age 67 years, range 52 to 84) evaluated preoperatively with CT imaging, 77 endograft candidates (68 men) were also assessed with intra-arterial DSA. Arterial parameters were measured on axial CT scans and angiographic films for comparison. Mean maximum AAA diameter was 58 +/- 11 mm (range 39 to 95). Aneurysmal neck diameter was consistently smaller on DSA than on CT (20.7 +/- 3.6 mm versus 23.0 +/ 3.5 mm, p < 0.0001). The distance from the most distal renal artery to the aortic bifurcation was longer on angiography than on CT (mean difference 10.0 mm, p < 0.0001). There was a positive correlation between the maximum AAA diameter and the AAA length (r = 0.49, p < 0.0001) and an inverse relationship between the neck length and the neck diameter (r = -0.36, p < 0.0001). No correlation was found between the maximum AAA diameter and maximum iliac diameter, angulation, or length. AAA anatomy varies widely and independently of the aneurysm size. Therefore, the maximum size of the aneurysm is a poor predictor of whether or not an aneurysm is suitable for endovascular repair. The discrepancy between angiographic and axial CT measurements suggests that neither alone is sufficient as a preoperative imaging technique when evaluating a patient for an endovascular graft procedure.

This article reports midterm results from endoluminal repair of abdominal aortic aneurysms (AAAs). Between November 1993 and July 1997, 81 patients were treated using endovascular stent grafts. The configuration of the stent grafts was aorto-aortic in 2 patients, bifurcated in 21 patients and aorto-monoiliac in 57 patients. The mean diameters of the AAAs and of the common iliac arteries were 59 mm (range 39 to 95 mm) and 16.5 mm (9 to 53.5 mm), respectively. Contrast-enhanced spiral CT and DSA were used for preoperative imaging evaluation and for follow-up 1 month after stentgraft placement. Contrast-enhanced spiral CT was repeated at 3, 6, and 12 months postoperatively and thereafter biannually. There were 7 immediate conversions. Technical success was achieved in 74 patients (91%). Seven complications occurred during stent-graft deployment. Percutaneous reinterventions were performed on 35 occasions in 28 patients. The most frequent was stent placement due to kinks caused by distal stent-graft migration. Twenty patients underwent repeated surgery on 24 occasions, including seven late conversions due to: total migration (n = 6) and late proximal perigraft endoleak (n = 1); and seven required stent-graft extensions: six proximal ones due to migration and one distal one due to endoleak. Thus, complications occurred in 57 patients (77%). Thirty days mortality was 6% including four patients who were rejected for open surgical repair. We concluded that endoluminal repair of AAAs with complex arterial morphology is technically possible. Patients unfit for open surgery run a high risk for serious complication if their arterial anatomy is not favorable. Distal migration of stent-grafts raises the question of long-term durability.