Faculty Bibliography

We report the case of a 78-year-old man with coronary artery disease, chronic obstructive pulmonary disease, and chronic renal insufficiency with an enlarging 6.7-cm infrarenal abdominal aortic aneurysm. He also had a 4-cm right common iliac artery aneurysm, and right external iliac artery occlusion. The patient had a history of an axillobifemoral bypass graft placed 10 years prior for aortoiliac occlusive disease. We describe the use of an infrarenal aorto-uni-iliac graft and subsequent intentional graft occlusion as an endovascular solution to treat aneurysmal disease in this sick patient. He remains asymptomatic after surgery, with demonstrated occlusion of his aneurysms.

BACKGROUND: A 61-year-old man with a previous endovascular repair and stage 5 chronic kidney disease presented with a symptomatic 4.5-cm left internal iliac artery aneurysm. The decision was made to proceed with endovascular repair. METHODS: The preoperative magnetic resonance angiography (MRA) scan was linked to on-table rotational imaging using the Artis zeego Fusion program (Siemens AG, Forchheim, Germany). Using the fused image as a road map, we undertook coil embolization of the left internal iliac artery, and a tapered stent graft was extended from the previous graft into the external iliac artery. RESULTS: Completion angiography revealed exclusion of the aneurysm sac. Three milliliters of contrast were used throughout the procedure. A follow-up magnetic resonance angiography scan at 1 month and duplex ultrasonography at 1 year revealed continued exclusion of the aneurysm sac. The patient's renal function remained unchanged. CONCLUSIONS: This case shows that in a patient with severe chronic kidney disease, fusion of preoperative imaging with intraoperative rotational imaging is feasible and can limit significantly the amount of contrast used during a complex endovascular procedure.

BACKGROUND: The incidence of concomitant carotid artery stenosis and unruptured intracranial aneurysms (UIAs) has been reported at between 0.5% and 5%. In these patients, treatment strategies must balance the risk of ischemic stroke with the risk of aneurysmal rupture. Several studies have addressed the natural course of UIAs in the setting of carotid revascularization; however, the final recommendations are not uniform. The purpose of this study was to review our institutional experience with concomitant UIAs and carotid artery stenosis. METHODS: We performed a retrospective review of all patients with carotid artery stenosis who underwent carotid artery endarterectomy (CEA) or carotid artery stenting (CAS) at our institution between 2003 and 2010. Only patients with preoperative imaging demonstrating intracranial circulation were included. Charts were reviewed for patients' demographic and clinical data, duration of follow-up, and aneurysm size and location. Patients were stratified into 2 groups: carotid artery stenosis with unruptured intracranial aneurysm (CS/UIA) and carotid artery stenosis without intracranial aneurysm (CS). RESULTS: Three hundred five patients met the inclusion criteria and had a total of 316 carotid procedures (CAS or CEA) performed. Eleven patients were found to have UIAs (3.61%) prior to carotid revascularization. Male and female prevalence was 2.59% and 5.26% (P = 0.22), respectively. Patients' demographics did not differ significantly between the 2 groups. The average aneurysm size was 3.25 +/- 2.13 mm, and the most common location was the cavernous segment of the internal carotid artery. No patient in the study had aneurysm rupture, and the mean follow-up time was 26.5 months for the CS/UIA group. CONCLUSIONS: Concomitant carotid artery stenosis and UIAs is a rare entity. Carotid revascularization does not appear to increase the risk of rupture for small aneurysms (<10 mm) in the midterm. Although not statistically significant, there was a higher incidence of aneurysms found in females in our patient population.

BACKGROUND: Endoleak and sac growth remain unpredictable occurrences after EVAR, necessitating regular surveillance imaging, including CT angiography. This study was designed to identify preoperative CT variables that predict AAA remodeling and sac behavior post-EVAR. METHODS: Pre- and postoperative CT scans from 136 abdominal aortic aneurysms treated with EVAR were analyzed using M2S (West Lebanon, NH) software for size measurements. Preoperative total sac volume and proportion of thrombus and calcium in the sac were assessed. Sac change was defined as a 3-mm difference in diameter and a 10-mm(3) difference in volume when compared with preoperative measurements. Univariate analysis was performed for age, gender, AAA size, relative thrombus/calcium volume, device type, presence of endoleak, and the effects on sac size. RESULTS: Gender, device type, age, AAA size, and percent calcium were not predictive of sac change post-EVAR. Increased proportion of thrombus on pre-EVAR resulted in a greater likelihood of sac shrinkage (P = 0.002). Patients with aneurysms that grew on postoperative CT scan had less sac thrombus on pre-EVAR (mean 27.5%) than patients without evidence of endoleak (mean 41.9%, P < 0.0001). Only 2 of 30 patients with >50% pre-EVAR thrombus developed endoleak. A >50% thrombus burden resulted in endoleak in significantly fewer patients (6.7%) compared with those who had <50% thrombus (43.1%). CONCLUSIONS: The proportion of thrombus on preoperative CT may predict sac behavior after EVAR and development of an endoleak. Greater than 50% thrombus appears to predict absence of endoleak after EVAR. Aneurysms with large thrombus burden are less likely to grow and may require less vigilant postoperative surveillance than comparable AAA with relatively little thrombus.

Background: Uncomplicated type B dissections have been traditionally managed with antihypertensive therapy. In the endovascular era, this dictum has been revisited. This review pooled the available studies to compare the outcomes of best medical therapy (BMT) to thoracic endovascular aortic repair (TEVAR) for uncomplicated type B dissections. Methods: A literature search was performed to identify studies on uncomplicated type B dissections managed with BMT with and without TEVAR. The primary outcome measures were mortality rates at 30 days and at 2 years following intervention. Results: A total of 6 studies included 123 patients who underwent TEVAR/BMT, and 566 patients who had BMT alone. The mortality rates at 30 days (6.5% TEVAR/BMT vs 4.8% BMT, P = .21) and at 2 years (9.7% vs 11.9%, P = .32) were similar. Renal failure was greater in TEVAR/BMT (15.4% vs 2.1%, P < .01). Rates of surgical reintervention/intervention were similar (17.6% vs 20.1%, P = .31). Conclusion: The TEVAR with BMT does not provide survival benefit compared to BMT alone, 2 years following uncomplicated type B aortic dissection.

The optimal treatment of patients facing imminent amputation after multiple (>/=2) failed prior ipsilateral bypasses is unclear. We analyzed a group of patients undergoing multiple lower extremity bypasses for limb salvage to assess the utility of attempting multiple revascularizations. From 1990 to 2005, 105 revascularization procedures were performed in 55 limbs of 54 patients with imminent limb-threatening lower extremity ischemia after failure of >/=2 prior infrainguinal bypasses in the same leg. Fifty-five operations were the third procedure (Group A) and 50 operations were the fourth or more (Group B). We compared primary/secondary patency and limb salvage rates by Society for Vascular Surgery criteria. Limb salvage rates did not differ between patients undergoing a third bypass and those undergoing four or more bypasses at one year (62 versus 65%, NS) or at three years (58 versus 61%, NS). Secondary patency was not different between groups (76 versus 76%, P = NS) at one and three years (71 versus 70%, NS). Primary patency also did not differ between the two groups, at one year (24 versus 35%, NS), or at three years (11 versus 15%, NS). No differences were observed in morbidity and mortality rates between the groups. In conclusion, the likelihood of success of repetitive limb revascularization was unrelated to the number of previous failures. The expected incremental failure rate with each successive bypass was not found. These results, coupled with the three-year limb salvage rate of over 50% in patients who otherwise would have required amputation, lend support to aggressive use of limb revascularization in selected patients even after two or more failed bypasses.

BACKGROUND: Prosthetic grafts for lower-extremity bypass have limited patency compared with autologous vein grafts. Precuffed expanded polytetrafluoroethylene (ePTFE) grafts alter the geometry of the distal hood to improve patency. This study reports the authors' long-term results on the use of precuffed ePTFE grafts for infrainguinal bypasses in patients with arterial occlusive disease and compares these with results of reversed great saphenous vein grafts (rSVG). METHODS: A retrospective review of billing codes identified 101 polytetrafluoroethylene (PTFE) and 47 rSVG bypasses performed over a 6-year period. Femoral to below-knee popliteal and femoral to tibial bypasses were analyzed. Data collected consisted of risk factors, Rutherford classification, bypass inflow and outflow, runoff vessels, patency, amputation, and death. Primary end points consisted of primary, assisted-primary, and secondary patency along with limb salvage. RESULTS: Mean age of the patients was 76 years in the PTFE group and 69.8 years in the rSVG group. For femoral to below-knee popliteal bypasses, primary patency at 1, 3, and 5 years in the PTFE group was 76.9%, 48.7%, and 43.3%, respectively, compared with 77.1%, 77.1%, and 77.1%, respectively, in the rSVG group (P = 0.225). Secondary patency was 89.2%, 70.9%, and 50.6% in the PTFE group compared with 84.4%, 84.4%, and 84.4% in the rSVG group (P = 0.269). Limb salvage was similar in the PTFE compared with the rSVG group (97.7%, 90.5%, and 79.4% vs. 83.3%, 83.3%, and 83.3%; P = 0.653). For femoral to tibial bypasses, primary patency in the PTFE group at 1, 3, and 5 years was 57.1%, 40.4%, and 22.1%, respectively, compared with 67.4%, 67.4%, and 50.6%, respectively, for the rSVG group (P = 0.246). Secondary patency was 75.5%, 44.9%, and 22.7% in the PTFE group compared with 91.8%, 91.8%, and 52.5% in the rSVG group (P = 0.022). Limb salvage at 1, 3, and 5 years was 79.2%, 55.7%, and 55.7%, respectively, in the PTFE group compared with 96.4%, 96.4%, and 64.3%, respectively, in the rSVG group (P = 0.046). CONCLUSIONS: Precuffed ePTFE grafts demonstrate similar 1-year patency to that of rSVG. However, mid- and long-term patency is reduced compared with saphenous vein grafts (SVG), especially to tibial targets. PTFE grafts to the popliteal demonstrate limb salvage rates similar to those of SVG. In the tibial vessels, limb salvage rates for PTFE grafts are significantly worse compared with SVG.

Endovascular aneurysm repair is being used increasingly to treat ruptured abdominal aortic aneurysms (RAAAs). Approximately 25% of RAAAs undergo complete circulatory collapse before or during the procedure. Patient survival depends on obtaining and maintaining supraceliac balloon control until the endograft is fully deployed. This is accomplished with a sheath-supported compliant balloon inserted via the groin contralateral to the side to be used for insertion of the endograft main body. After the main body is fully deployed, a second balloon is placed within the endograft, and the first balloon is removed so that extension limbs can be placed in the contralateral side. A third balloon can be placed via the contralateral side and ipsilateral extensions deployed as necessary. This technique of supraceliac balloon control is important to achieving good outcomes with RAAAs. In addition to minimizing blood loss, this technique minimizes visceral ischemia and maintains aortic control until the aneurysm rupture site is fully excluded.