Faculty Bibliography

Endovascular grafting is a technique that combines the use of intravascular stents and prosthetic grafts to fabricate devices with unique properties. The purpose of this study is to describe the use of endovascular graft technology in the treatment of failed or failing standard aortoiliofemoral reconstructions. Over a 15-month period five patients with limb-threatening ischemia and failed aortofemoral or iliofemoral reconstructions underwent successful placement of six endovascular grafts to revascularize seven severely ischemic lower extremities. Standard thin-walled 6 mm polytetrafluoroethylene grafts and Palmaz balloon-expandable stents were used to fashion each reconstruction. In addition to the primary endovascular grafts, three patients underwent immediate femoropopliteal bypasses to improve distal outflow and one patient had a femorofemoral bypass graft to restore circulation to the contralateral ischemic extremity. The ankle/brachial indices of all patients significantly improved after the procedure (from a mean of 0.32 to a mean of 0.75) and all grafts are patent to date (mean follow-up 10 months). There were no deaths or limb loss in this group of patients. These favorable results indicate that this minimally invasive approach, which permits a new arterial graft to be inserted through a remote access site, is a valuable method for providing unobstructed arterial inflow after aortoiliofemoral graft failure. This procedure may be particularly valuable when there are contraindications to the use of axillary arteries or the thoracic aorta as alternatives to complex reoperative abdominal aortic surgery

Endovascular aortic graft implantation is a new procedure for the repair of arterial aneurysms. We report on the first such case successfully performed in the United States. A 76-year-old man with severe oxygen-dependent pulmonary insufficiency, coronary artery disease, and recurrent ventricular tachyrhythmia was also diagnosed as having a 7.5-cm infrarenal abdominal aortic aneurysm. Because of the high risks associated with conventional surgical repair, consent was obtained for compassionate use of an experimental device. Using local anesthesia, a 22-mm Dacron prosthesis was inserted under fluoroscopic guidance through an open, left transfemoral route. Completion arteriography demonstrated aneurysm exclusion. No blood transfusion was required and there were no perioperative complications. Further technical refinements and clinical trials will be required prior to the broad implementation of this technique

OBJECTIVES: Complex arterial occlusive, traumatic, and aneurysmal lesions may be difficult or impossible to treat successfully by standard surgical techniques when severe medical or surgical comorbidities exist. The authors describe a single center's experience over a 2 1/2-year period with 96 endovascular graft procedures performed to treat 100 arterial lesions in 92 patients. PATIENTS AND METHODS: Thirty-three patients had 36 large aortic and/or peripheral artery aneurysms, 48 had 53 multilevel limb-threatening aortoiliac and/or femoropopliteal occlusive lesions, and 11 had traumatic arterial injuries (false aneurysms and arteriovenous fistulas). Endovascular grafts were placed through remote arteriotomies under local (16[17%]), epidural (42[43%]), or general (38[40%]) anesthesia. RESULTS: Technical and clinical successes were achieved in 91% of the patients with aneurysms, 91% with occlusive lesions, and 100% with traumatic arterial lesions. These patients and grafts have been followed from 1 to 30 months (mean, 13 months). The primary and secondary patency rates at 18 months for aortoiliac occlusions were 77% and 95%, respectively. The 18-month limb salvage rate was 98%. Immediately after aortic aneurysm exclusion, a total of 6 (33%) perigraft channels were detected; 3 of these closed within 8 weeks. Endovascular stented graft procedures were associated with a 10% major and a 14% minor complication rate. The overall 30-day mortality rate for this entire series was 6%. CONCLUSIONS: This initial experience with endovascular graft repair of complex arterial lesions justifies further use and careful evaluation of this technique for major arterial reconstruction

PURPOSE: The purpose of this study was to perform a preliminary histopathologic analysis of explanted human endovascular stented grafts from patients treated for occlusive disease. METHODS: Over a 16-month period, 26 endovascular stented grafts were placed in 21 patients with limb-threatening ischemia caused by aortoiliac or femoral artery occlusive disease. All grafts were inserted through open arteriotomies remote from the region of primary disease. During the follow-up period, two patients died of preexisting heart disease 2 weeks and 7 months after grafting, and a portion of their endovascular grafts were the surrounding artery was explanted. Specimens from five other endovascular grafts were obtained during surgical revision for graft stenosis after 3 and 6 weeks and for outflow artery stenosis after 3, 5, and 6 months. All specimens were formalin fixed and studied with hematoxylin and eosin and trichrome staining and immunohistochemically for factor VIII-related antigen, alpha actin smooth muscle, macrophage antigen (MAC-387) and PC-10 (a mouse monoclonal antibody which specifically recognizes proliferating cell nuclear antigen in paraffin sections). RESULTS: Three weeks after placement of the stented grafts, organizing thrombus was present on both surfaces of the expanded polytetrafluoroethylene (PTFE) grafts. At 6 weeks, evidence of a neointima with overlying endothelium was seen in the perianastomotic region, and 3 months after grafting it was seen 1 to 3 cm from the anastomosis. The specimen explanted at 5 months demonstrated factor VIII-positive cells 8 cm from the anastomosis. The histopathologic condition of the external capsule appeared to vary, depending on the presence or absence of an external wrap on the PTFE graft and on which layer in the arterial wall the graft was inserted. A foreign body reaction characterized by multinucleated giant cells was seen adjacent to wrapped grafts or around those placed in an intraadventitial plane. Grafts inserted within the media were surrounded by orderly, arranged, smooth muscle cells and few mononuclear cells. Extensive smooth muscle cell proliferation (PC-10 activity) was not seen within native artery atherosclerotic plaques peripherally displaced and external to prosthetic endovascular grafts. CONCLUSIONS: These preliminary observations on the healing of PTFE endovascular stented grafts in human beings demonstrate limited plaque hyperplasia and the presence of endothelial cells on the luminal surface remote from the graft-artery anastomosis. It is unclear whether this is a unique manifestation of healing in prosthetic grafts inserted within the walls of arteries

OBJECTIVE. Transfemorally placed endoluminal grafts are currently being evaluated as an alternative to open surgery for the treatment of abdominal aortic aneurysms. We determined the value of helical CT for the follow-up of patients treated with this new procedure. The purposes of this study were to determine CT features of a technically successful procedure, detect complications, and compare findings on CT scans obtained 24-48 hr after insertion of the graft with findings on angiograms obtained at the end of the endovascular procedure. SUBJECTS AND METHODS. Seven patients with large abdominal aortic aneurysms had helical CT within 48 hr after transfemoral insertion of an endoluminal graft. Findings on these CT scans were compared with findings on digital completion angiograms obtained immediately after placement of the graft. Additional follow-up CT scans were obtained for up to 15 months (mean, 8 months). The size of the aneurysmal sac; completeness of perigraft thrombosis; and position, shape, and patency of the device were recorded. RESULTS. CT scans obtained 24-48 hr after placement of the grafts showed complete thrombosis of the aneurysmal sac in three patients and incomplete thrombosis with patent perigraft channels in the four remaining patients. Angiograms showed a patent perigraft channel in only one patient. Two of four initially patent channels subsequently closed, but one of them recurred. Of four thrombosed aneurysms, two decreased in size, and two were unchanged on later follow-up. Of three aneurysms associated with perigraft channels, two became enlarged and one was stable. On the basis of CT criteria, successful endovascular repair was shown in four (57%) of seven patients. CONCLUSION. Helical CT is a sensitive means of evaluating the efficacy of endoluminal grafts. Decreased or stable size of the aneurysmal sac without perigraft channels on late follow-up CT signifies technical success. Persistence or recurrence of perigraft channels is the most likely cause of later enlargement of an aneurysm and therefore suggests procedural failure. Helical CT was more sensitive than angiography for detection of perigraft channels that occurred soon after treatment

In high-risk patients endovascular repair of a pseudoaneurysm with a stented graft is a safe and reasonable treatment option that can preclude significant morbidity and shorten hospital stay. We report a case of pseudoaneurysm of the subclavian artery after internal jugular vein cannulation that was treated successfully with an endovascularly inserted, stented graft. The case report highlights the importance of recognizing this unusual but serious complication of percutaneous internal jugular vein catheterization through careful clinical examination, prompt duplex scanning, and arteriography

PURPOSE: The purpose of this report was to determine differences in presentation, bacteriology, management, and outcome of early (EGIs) versus late extracavitary arterial graft infections (LGIs). METHODS: Between July 1, 1979, and June 30, 1994, we treated 141 patients with infected extracavitary arterial grafts (112 prosthetic, 29 vein) with selective partial or complete graft preservation. RESULTS: A total of 99 (70%) EGIs (< 2 months) and 42 (30%) LGIs (4 to 96 months) were involved. The hospital mortality rate was 14% (20 of 141), and the amputation rate in survivors was 13% (16 of 121). No significant difference in mortality (16% [16 of 99] vs 10% (4 of 42]) or limb loss (16% [13 of 83] vs 8% [3 of 38]) was seen between EGIs and LGIs, respectively (p > 0.05). Patients with EGIs were as likely to have a disrupted anastomosis (17% [17 of 99] vs 21% [9 of 42]) or systemic sepsis (4% [4 of 99] vs 4% [2 of 42]) as patients with LGIs, respectively (p > 0.05). Patients with EGIs were more likely to have patent, intact grafts and to be treated by complete graft preservation (61% [61 of 99] vs 26% [11 of 42]) (p = 0.0001). In comparison, patients with LGIs were more likely to have occluded grafts and to require subtotal graft excision (48% [20 of 42] vs 18% [18 of 99]) (p = 0.0001). Surviving patients with EGIs treated by complete graft preservation were more likely to have successful healing of their wounds after long-term follow-up (average 3 years) than patients with LGIs (79% [41 of 52] vs 40% [4 of 10], respectively) (p = 0.03). The pathogens cultured from wounds of EGIs versus LGIs were pure gram-positive bacteria in 49 (49%) versus 19 (46%), pure gram-negatives in 18 (18%) versus 11 (26%), and both types in 33 (33%) versus 12 (28%) (p > 0.05). CONCLUSION: Complete graft preservation can be attempted more frequently and is more likely to be successful in EGIs than in LGIs. No difference in bacteriology was seen between the two groups. Graft-preserving treatment can be successful but should only be cautiously attempted in patients with late extracavitary arterial graft infections