John S. Butterfield

Device migration after endovascular abdominal aortic aneurysm repair: Experience with a talent stent-graft

PURPOSE Device migration (DM) may cause late failure after endovascular aortic aneurysm repair (EVAR). Computed tomography (CT) scans following EVAR were reviewed to establish the frequency of DM and whether it can be predicted. MATERIALS AND METHODS Fifty-five patients underwent EVAR with a Talent stent-graft with suprarenal fixation. CT with a fixed protocol was performed at regular intervals. Patient demographics, risk factors, procedure details, and follow-up events were reviewed. Two observers, blinded to each other, reviewed axial images and mutliplanar reformats of the CT scans. DM was defined as a change of > or = 10 mm in the distance between a reference vessel (celiac axis/superior mesenteric artery) and the proximal device. Follow-up was performed for a minimum of 2 years (mean, 3 years; range, 2-5 years). RESULTS DM was detected in six of 38 patients (15.8%) by 2 years. There were no new cases of migration in the 19 patients at 3 years but one new case in the six patients at 4 years (16.6%). Mean migration over 2 years was 4.8 mm +/- 4.2 mm. One patient with DM developed a type I endoleak that required reintervention. This patient developed a further endoleak and died following surgery for rupture. Top neck enlargement was the only predictive factor identified, present in 71% of patients with DM (P = .056). CONCLUSION DM occurred in a small proportion of patients; closer follow-up intervals may be necessary in patients with short/enlarging proximal necks.

Midterm follow-up of a single-center experience of endovascular repair of abdominal aortic aneurysms with use of the Talent stent-graft.

PURPOSE To review the midterm results of endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs) with the Talent stent-graft. MATERIALS AND METHODS All patients who underwent EVAR of AAAs with Talent stent-grafts from February 1998 to April 2002 at a single institution were monitored for a minimum of 2 years or until an endpoint of death or rupture was reached. RESULTS There were 68 eligible patients, who were monitored for a mean period of 39 months (range, 24-72 months). Forty-nine (72.9%) were alive at 2 years; among the 19 deaths, two resulted from aneurysm rupture and the other 17 were unrelated to EVAR. There was one immediate conversion to open repair and five primary proximal endoleaks; the remaining 62 patients (91.2%) all had a technically successful procedure. There were 33 endoleaks during follow-up: 23 (69.7%) were treated conservatively and 10 (30.3%) underwent secondary intervention in the form of embolization (n=2), attempted embolization (n=2), endovascular stent-graft placement (n=3), combined stent-graft placement and embolization (n=1), or surgical conversion (n=2). Overall, there were five persistent endoleaks, and the remaining patients were free of endoleak at their last review or endpoint. Three stent-grafts migrated and required further endovascular intervention. Wire fracture was seen in two stents but presented no clinical sequelae. There was one case of graft limb thrombosis that required surgical thrombectomy. CONCLUSIONS EVAR of AAAs with use of the Talent stent-graft is a promising and acceptable alternative to open surgery. Our 30-day mortality rate of zero compares extremely well with historical data from open surgery and the findings of more recently published trials. The risk of endoleak and uncertainty over durability require long-term surveillance.

Endovascular stent graft: treatment of pseudoaneurysm of the superior mesenteric artery.

Splanchnic artery aneurysms are rare with an incidence of between 0.1 and 2% [1]. Superior mesenteric artery aneurysms (SMAA) are the third most common after splenic and hepatic artery aneurysms and represent approximately 7% of visceral artery aneurysms [2]. They are clinically important as rupture can result in fatal hemorrhage [2]. Previously described surgical management has included ligation, resection and/or bypass. Endovascular treatment has been mainly limited to transcatheter embolization. We describe a case of SMAA secondary to pancreatitis causing obstructive jaundice and treated by an endovascular stent graft, an approach not previously reported.

Multicenter retrospective investigation into migration of fenestrated aortic stent grafts

OBJECTIVE Fenestrated stent grafts are subject to the same hemodynamic forces that have resulted in migration of standard infrarenal stent grafts. Outcome data for fenestrated endovascular aneurysm repair consist of short-term and midterm efficacy studies where migration was generally poorly investigated. This study investigated the migration of fenestrated stent grafts in patients treated by fenestrated endovascular aneurysm repair in the United Kingdom. METHODS A total of 154 patients were retrospectively enrolled from nine sites across the United Kingdom. Patients had been treated with a Zenith fenestrated endograft (Cook Medical, Bloomington, Ind) between 2003 and 2010. Patients were required to have a baseline (first) postoperative computed tomography (CT) scan and at least one additional CT scan available. Measurements from the proximal stent graft to the superior mesenteric artery and from the distal stent graft to the iliac bifurcation were performed on the first postoperative CT scan. These measurements were repeated on all subsequent CT scans, and differences between the baseline and subsequent CT scans for the same anatomical location were suggestive of device migration. Migration was defined as cranial (-) or caudal (+) movement of the stent graft of ≥4 mm. RESULTS Proximal migration (median, +6.0 mm; range, +4.1 to +10.0 mm) was evident in 33 patients (21%). The probability of being free from proximal migration at 12, 24, and 36 months was estimated as 82% (95% confidence interval [CI], 75%-89%), 77% (95% CI, 70%-85%), and 77% (95% CI, 70%-85%), respectively. Of 259 limbs assessed, 34 (13%) showed evidence of cranial migration (median, -6.1 mm; range, -21.3 to -4.1 mm). The observed probability of being free from any iliac limb migration at 12, 24, and 36 months was 85% (95% CI, 79%-92%), 82% (95% CI, 75%-90%), and 65% (95% CI, 52%-80%), respectively. CONCLUSIONS Proximal migration occurs in approximately one-third of patients by 4 years, all migration was caudal in direction, with 60% <6.0 mm in length. Clinical sequelae were infrequent, with no statistically significant differences in the number of complications or reinterventions in patients with and without proximal migration.