Experience of reoperations followed by repairs of abdominal aortic aneurysms

We experienced 8 cases who required reoperations, including 2 re-redo operations, after repairs of infrarenal abdominal aortic aneurysms. Of 8 patients, one patient developed a new aneurysm due to atherosclerosis in thoraco-abdominal aorta involving all visceral arteries and other 7 patients had aneurysmal formations at proximal anastomotic sites, including 3 suprarenal, 2 juxtarenal and 2 infrarenal aortic lesions. Etiology at initial operation in patients who subsequently developed anastomotic aneurysms included vasculo-Beh?et disease in 4, atherosclerosis in 2 and dissecting aortic aneurysms type III due to Marfan syndrome in 1. At reoperation, all who had vasculo-Beh?et disease had ruptures of anastomotic sites and 2 patients underwent repairs of dehiscent patch, 1 extra-anatomic bypass between ascending and abdominal aorta and 1 interposition of graft. One patient who had graft infection after repair of abdominal aortic aneurysm required axillo-femoral bypass with removal of infected graft. A patient who had dehiscence of proximal anastomosis after repair of aortoiliac occlusive disease required interposition of graft. Two patients, Marfan syndrome and aneurysm in thoraco-abdominal aorta, underwent graft replacement of thoraco-abdominal aorta concomitant with reconstruction of all visceral arteries. There were 8 patients who required reoperations for aneurysms at distal anastomotic sites after repairs of abdominal aortic aneurysms. Five patients underwent repairs of new aneurysms, including replacement of total arch in 3, descending aorta in 1 and iliac artery in 1. In all cases, no hospital death was noted, however, late deaths were occurred in vasculo-Beh?et disease, Marfan syndrome and graft infection. Thus, late result depends on etiology of disease. Although patients who requires reoperation after repair of abdominal aortic aneurysms have higher operative risk factors, early and late results are satisfactory compared to initial operations.     

Anatomical suitability of abdominal aortic aneurysms for endovascular repair

BACKGROUND: Aortic aneurysm anatomy is crucial when considering patients for endovascular repair. The aim of this study was to determine the proportion of patients with aortic aneurysm suitable for endovascular repair with three different graft-stent systems. METHODS: Spiral computed tomographic angiography was used to assess the anatomy of 154 abdominal aortic aneurysms. Measurements were made of aneurysm neck length and diameter, renal artery to aortic bifurcation length, common iliac artery diameter and length, and external iliac artery diameter. Aneurysms were assessed for anatomical suitability for currently available aortoaortic, aortobi-iliac and aortouni-iliac devices. RESULTS: Six patients (4 per cent) had a distal aortic neck suitable for implantation of a straight aortic graft. Fifteen patients (10 per cent) had arterial anatomy suitable for implantation of a bifurcated graft and 85 (55 per cent) patients were suitable for endovascular repair with an aortouni-iliac graft. The primary reasons for unsuitability were: proximal neck length less than 1.5 cm (44 patients), proximal neck diameter greater than 3.0 cm (12), and angulation of the proximal neck (three). A further ten patients were considered unsuitable for an aortouni-iliac graft because of bilateral common iliac artery aneurysms (four), tortuous iliac arteries (four) and narrow external iliac arteries (two). CONCLUSION: The aortouni-iliac device has the widest applicability of the currently available endovascular systems but open repair remains the only option for a large proportion of patients.     

Anterior patch aortic aneurysm model for the study of endoluminal grafts

Endovascular graft repair for aortic aneurysms has led to concerns regarding the healing characteristics of the graft within a thrombus-lined aneurysm and the effect that collateral flow may have on the endoluminal prosthesis and the aneurysm. An anterior aortic patch aneurysm model that preserved collateral arteries was examined and modified to address these issues. In canines (n = 30) a Dacron knitted patch (n = 27) or a rectus fascia patch (n = 3) was sutured into a 3.5-cm anterior aorotomy. Dacron patch aneurysm diameter was an average of 21.8 +/- 2.2 mm (mean canine normal aortic diameter 9.06 +/- 0.79 mm). Canines underwent angiogram, computed tomography, and/or intravascular ultrasound from 1 to 11 weeks later, at which time an endoluminal prosthesis was deployed and followed 30 to 60 days until harvest. Aneurysms accumulated minimal thrombus through the initial 11 weeks. Significant stenosis (mean 21.2% +/- 19%) occurred at aneurysm necks in association with a patch imbrication suture technique (n = 11). Following modification (n = 16), this decreased to a mean of 3.6 +/- 9.7%. Collateral lumbar artery patency was 95% at the time of imaging prior to graft placement. Following successful graft implantation, 16 of 18 aneurysms were filled with thrombus and in most cases the collateral circulation occluded. One of three fascial patch aneurysms ruptured 21 days after creation. This model more accurately depicts abdominal aortic aneurysms with the inherent thrombus and collateral flow that is important when studying aspects of endovascular aortic graft repair.     

Abdominal and thoracoabdominal aortic aneurysm

Most abdominal aortic aneurysms (AAA) and thoracoabdominal aortic aneurysms (TAAA) are asymptomatic and are found on physical exam or incidentally during radiological studies for other indications. These aneurysms are repaired primarily because their risk of rupture increases geometrically as the size exceeds 5 cm. The potential morbidity of intraoperative visceral and spinal ischemia involved with TAAA repair may be reduced with various adjunctive maneuvers.     

A case report of a successful surgery for thoracoabdominal aortic aneurysm under partial cardiopulmonary bypass with selective perfusion of major abdominal branches

A 69-year-old man showed gradually developing thoracoabdominal aortic aneurysm (TAAA) after coronary artery bypass grafting. The patient underwent graft replacement of TAAA uneventfully under partial cardiopulmonary bypass with selective perfusion of major abdominal branches. The major abdominal branches and two pairs of intercostal arteries were reconstructed. The patient showed no organ failure or spinal damage postoperatively. Partial cardiopulmonary bypass with selective perfusion of abdominal branches successfully protected both the visceral organs and the spinal cord from ischemia in a TAAA surgery.     

Congenital malformations in infants of 517 pregestational diabetic mothers

PURPOSE: To explore a method of combined endovascular/conventional treatment of abdominal aortic aneurysm (AAA), in which the iliac arteries are reconstructed by conventional surgical techniques to provide the anatomic substrate for subsequent endovascular repair of the aortic aneurysm. METHOD: A 77-year-old patient with severe cardiac disease was found to have a 6.5-cm AAA, bilateral common iliac artery (CIA) aneurysms, and diffusely narrowed, tortuous external iliac arteries. The left internal iliac artery was occluded. At operation, the right CIA was exposed through a transverse retroperitoneal incision under epidural anesthesia. An iliobifemoral bypass was constructed using a preformed bifurcated graft. A stent-graft was delivered through the right limb of the bifurcated iliobifemoral graft. The proximal end of the stent-graft was implanted in the neck of the aneurysm, and the distal end was deployed in the common trunk of the iliobifemoral graft, thereby excluding the AAA and both native iliac arteries from prograde arterial flow. RESULTS: Completion angiography and follow-up contrast computed tomography showed the aneurysm to be excluded from the circulation. The patient was not intubated, was never hemodynamically unstable, and had aortic blood flow interrupted for no more than 20 seconds. In addition, he was able to resume his usual diet on the first postoperative day. He continues to be well and without evidence of endoleak at 6-month follow-up. CONCLUSIONS: This case demonstrates that iliac artery stenosis, tortuosity, and aneurysmal dilatation are not impediments to endovascular AAA exclusion. Any necessary surgical modifications of pelvic arterial anatomy can be performed before stent-graft insertion to minimize aortic occlusion time.     

Reoperation after repair of type A and B dissecting aneurysm

BACKGROUND: In the late postoperative period after repair of an aortic dissection or dissecting aneurysm, reoperations may be required. The interval to reoperation, size and location of intimal tear, and results of reoperation were evaluated. METHODS: Between January 1982 and April 1997, 138 patients underwent surgery for Stanford type A (90 patients) or type B (48 patients) dissections of the aorta. The entire aorta was evaluated in postoperative follow-up by computed tomography and magnetic resonance imaging for 6 months to 15 years. Reoperations were performed in 14 (10.1%) patients with changes in the aneurysms at the site of the initial repair or in the distal aorta. Selective cerebral perfusion or retrograde cerebral perfusion with deep hypothermia was used in the repair of the ascending, arch, and distal arch aneurysms. Reoperations included aortic root reconstruction (n=3), resection of a pseudoaneurysm (n=1), and replacement of the ascending aorta (n=1), arch (n=5), descending aorta (n=2), thoracoabdominal aorta (n=1), or abdominal aorta (n=1). Secondary reoperations were performed in four patients (replacement of the arch [n=2], thoracoabdominal aorta and abdominal aorta). Consequently two patients had subtotal aortic replacements. The aneurysms were caused by an anastomotic leak, a new intimal tear following aortic cross-clamping, a second intimal tear in the distal arch or abdominal aorta, and Marfan syndrome. RESULTS: Two patients (2/18 11.1%) died of bleeding or low output syndrome. Two patients died of graft infection or prosthetic valve infection 3 months after surgery respectively. CONCLUSIONS: 1) The surgical results of reoperation for type A and B dissections were good. 2) Close postoperative follow-up of the patent false lumen in the entire aorta was necessary. 3) At the initial operation, total resection of the intimal tear in the aortic arch in low-risk patients reduced the risk of reoperation.     

Successful treatment of bilateral deep femoral aneurysms and multiple iliac aneurysms associated with severe aortic valve disease: report of a case

We report herein the case of a patient in whom aneurysms of the bilateral deep femoral arteries (DFA) and multiple iliac aneurysms associated with severe aortic valve disease were successfully treated by a two-staged operation. The patient was a 74-year-old man who had dense calcification of the ascending aorta and aortic arch. Prior to aortic valve replacement (AVR), the aneurysms of the DFA and internal iliac arteries were resected. The terminal end of the abdominal aorta and bilateral common iliac arteries were then reconstructed with a Y graft to be used as a possible alternative arterial input route in place of the ascending aorta for extracorporeal circulation during the AVR. The inferior mesenteric artery (IMA) was well developed, and the external iliac arteries and their branches were preserved at aneurysmectomy. Postoperatively, there was no ischemia of the pelvic organs or the hip muscles. The AVR was subsequently performed 5 weeks after the first operation, and the patient was discharged after an uneventful postoperative course.     

Impact of retrograde cerebral perfusion with posterolateral thoracotomy on distal arch aneurysm repair

BACKGROUND: Repair of distal aortic arch aneurysms is difficult to accomplish through a median sternotomy or left thoracotomy, and stroke and respiratory disorders often become lethal complications with the use of circulatory arrest. We investigated the use of retrograde cerebral perfusion with a posterolateral thoracotomy in the repair of distal arch aneurysms. METHODS: Thirty-eight patients underwent repair of a distal arch aneurysm. They were divided into three groups according to the method of surgical repair used. Sixteen patients (group I) underwent proximal anastomosis of the graft with the use of an aortic cross-clamp. Eight patients (group II) underwent open proximal anastomosis with the use of retrograde cerebral perfusion (oxygenated blood perfusion through a superior vena cava cannula) and a median sternotomy and anterolateral thoracotomy. Fourteen patients (group III) also underwent open anastomosis with the use of retrograde cerebral perfusion (cerebral perfusion through blood returned to the right atrium with the patient in the Trendelenburg position) and a posterolateral thoracotomy. RESULTS: The operative mortality rate in group I was 25.0%; 4 of 16 patients died of stroke, myocardial infarction, and intestinal necrosis. In group II, 3 of 8 patients (37.5%) died of respiratory failure and aortic dissection. In group III, only 1 of 14 patients (7.1%) died, as a result of heart failure. CONCLUSIONS: The use of retrograde cerebral perfusion with a posterolateral thoracotomy is an alternative method that minimizes the risk of stroke and respiratory failure during distal aortic arch operations.     

Electron-beam CT-angiography in abdominal aortic aneurysms. Initial results

PURPOSE: To evaluate the suitability of ultrafast electron-beam tomography (EBT) for the investigation of abdominal aortic aneurysms using CTA. METHODS: Thirty-one patients with suspected abdominal aortic aneurysm were investigated with EBT using an Evolution XP scanner (Siemens, Erlangen) with the newest software version 12.34 with continuous volume scanning of 140 images in 17 s. Collimation was 3 mm, table increment 4 mm with overlapping image reconstruction every 2 mm, exposure time 200 ms (124 mAs), resulting in a scan-range of 28 cm. A quantity of 80 ml contrast material was administered (flow 4 ml/s). Visualization of the abdominal aorta and its branches was performed with MIPs and shaded surface display. Evaluation of image quality was based on a four-step classification scale (1 = good, 4 = insufficient) for the demonstration of the abdominal aorta and the visceral, renal and iliac arteries. RESULTS: All EBT examinations demonstrated high and homogeneous density values along the whole vessel course with a mean density value of 258.7 +/- 47.3 HU for the abdominal aorta and the iliac arteries. Quality evaluation for the vessel demonstration showed mean values between 1.22 and 1.57 for the abdominal aorta and the visceral, renal and iliac arteries. CONCLUSIONS: EBT with 140 slices and slice reconstruction every 2 mm offers a high z-axis resolution resulting in high-quality CT angiographies of the whole abdominal aorta and its branches.     

Importance of intercostal artery reattachment during thoracoabdominal aortic aneurysm repair

PURPOSE: We studied the relationship of neurologic deficit to ligation, reimplantation, and preexisting occlusion of intercostal arteries to determine which arteries and consequent management are most critical to outcome in thoracoabdominal aortic aneurysm repair. METHODS: From February 1991 to July 1996, 343 patients with thoracoabdominal aortic aneurysms underwent repair by one surgeon. In this study, only Crawford types I, II, and III (n = 264) were considered. Of these, 110 (42%) were type I, 116 (44%) type II, and 38 (14%) type III. The adjuncts of distal aortic perfusion and cerebrospinal fluid drainage were used in 164 patients (62%). Data were analyzed by contingency table and by multiple logistic regression. RESULTS: Early neurologic deficit occurred in 23 patients (8.7%), and late deficit in 10 patients (3.8%). Neurologic deficit in patients with at least one reimplantation and no ligation of arteries T11 or T12 occurred in 19 of 147 (12.9%). Neurologic deficit for occlusion of the same arteries occurred in 11 of 111 (9.9%), whereas for ligation of T11 and T12 neurologic deficit occurred in three of six (50%; reimplantation, p < 0.03; occlusion, p < 0.006). In addition, reimplantation of intercostal arteries T9 or T10 was significantly associated with reduced late neurologic deficit in multivariate analysis (p = 0.05). No other intercostal artery status was associated with modification of the neurologic deficit rate. Multivariate analysis showed type II aneurysms and acute dissections to be significantly associated with an increased risk of postoperative neurologic deficit (p < 0.0009, 0.002, respectively). Adjuncts were protective (p < 0.007), most often in types II and III (14.1% neurologic deficit in type II with adjunct, 35.3% without; 0% in type III with adjunct, 20% without). CONCLUSION: Patients with patent arteries at the T11/T12 level have highly variable outcomes depending on whether the arteries are reattached or ligated. Our data suggest that reimplantation of thoracic intercostal arteries T11 and T12 is indicated when these arteries are patent. Reimplantation of T9 and T10 lowers the risk of late neurologic deficit, probably by decreasing the spinal cord's vulnerability to changes in blood and cerebrospinal fluid pressure in the days after surgery. Adjuncts lower overall risk and provide adequate time for targeted intercostal artery reimplantation.     

Non clamping anastomosis of the ascending and arch aneurysm using retrograde cerebral perfusion

Twelve consecutive patients requiring surgery for replacement of ascending aortic aneurysms (n = 3), ascending arch aortic aneurysms (n = 2), or type A aortic dissections (n = 7) were treated without aortic cross clamping. Retrograde cerebral perfusion (RCP) with circulatory arrest (mean RCP time: 46.0 +/- 15.9 minutes, range 20 to 65 minutes) and continuous retrograde cardioplegia (mean cardiac ischemic time: 134.4 +/- 39.7 minutes, range: 40 to 180 minutes) were employed. In the patients with aortic dissection, the intimal tear at the origin of the brachiocephalic artery (BCA) was resected completely, the aortic wall was trimmed and closed with Teflon felt. The distal anastomosis was created using an open technique. Air and debris were completely evacuated by returning blood from the cerebral vessels and femoral artery. Then the artificial graft was clamped, and cardiopulmonary bypass resumed. The proximal anastomosis was performed during rewarming. The operations were elective in seven cases, and emergent in five cases. Graft replacement of the ascending aorta was performed in ten patients (including two BCA reconstructions). The remaining two patients were treated by patch repair (n = 1), primary anastomosis (n = 1). There were no perioperative deaths. One patient had a transient neurological deficit. The distal false lumen was occluded completely in five of seven patients with aortic dissections. The other two patients had a secondary tears in the descending aorta. Thus retrograde cerebral perfusion and continuous retrograde cardioplegia without aortic cross clamping is an effective technique in the replacement of the ascending and arch aorta.     

Electronic access to mouse tumor data: the Mouse Tumor Biology Database (MTB) project

BACKGROUND: Single-stage extensive replacement of the thoracic aorta usually involves a period of circulatory arrest with performance of the graft-to-lower descending thoracic aorta anastomosis before performing the anastomosis to the arch vessels. To minimize the period of brain ischemia and reduce the potential for neurologic injury, we developed an alternative technique. METHODS: In 6 patients with extensive aneurysms involving the entire thoracic aorta, exposure was obtained via a bilateral thoracotomy in the anterior fourth intercostal space with transverse sternotomy. A 10-mm graft was anastomosed to the aortic graft, opposite the site of the planned anastomosis to the arch vessels. During a single period of circulatory arrest (34-46 minutes), the aortic graft was attached to a cuff of aorta containing the arch vessels. The graft was then clamped on either side, and the arch was perfused with cold blood for 20 to 36 minutes. After the distal aortic anastomosis was completed, antegrade perfusion was established via the 10-mm graft. The proximal aortic anastomosis was performed last. RESULTS: No patient sustained a permanent neurologic deficit. All 6 patients were discharged from the hospital. CONCLUSIONS: The "arch-first" technique, combined with a bilateral transverse thoracotomy, allows expeditious replacement of the thoracic aorta with an acceptable interval of hypothermic circulatory arrest and minimizes the risk of retrograde atheroembolism by establishing antegrade perfusion.     

In situ autogenous reconstruction of the thoracoabdominal aorta and branches for treatment of an infected thoracoabdominal aortobifemoral bypass graft

Graft infection is an uncommon but potentially lethal complication of prosthetic aortic repair. We describe a novel technique for upper abdominal aortic and visceral revascularization after percutaneous drainage and antibiotics failed to cure a thoracofemoral prosthetic graft infection. One week after axillofemoral and femorofemoral bypass grafting, the infected thoracoabdominal graft was removed and a bifurcated iliac artery autograft was used to replace the upper abdominal aorta and revascularize the abdominal viscera. The infected graft was removed from the thorax and retroperitoneum, the infection resolved, and the patient remained well until his death of lung cancer 9 years later.     

Open distal anastomosis or aortic balloon occlusion technique during complete aortic arch replacement

The technique of open distal anastomosis or application of aortic balloon occlusion catheter designed to occlude the descending thoracic aorta have been used in 33 and 19 patients, respectively, to control bleeding during the procedure of distal anastomosis for complete aortic arch replacement with a prosthetic graft. These two techniques allowed us a simple approach to the lesion and the avoidance of clamp injury to the fragile aortic tissue. Open distal anastomosis was applied for 91% patients of operated aortic dissection and all emergent cases, it's duration ranged from 10 to 110 minutes with an average of 58 minutes under 18.2 degrees C of lowest esophageal temperature. On the other hand, aortic occlusion balloon was inserted for mainly true aortic aneurysm patients without an emergency, and helped to maintain the perfusion pressure on a lower part of body around 50 mmHg by the 1550 ml/min in an average of perfusion flow femoral artery under 21.2 degrees C of temperature. The difference of postoperative renal and liver function evaluated by serum enzyme levels of total bilirubin, GOT, GPT, LDH, creatinine and BUN did not reach to statistical significance between the patients using open distal anastomosis and balloon occlusion, however, the incidence of postoperative complication including either renal, liver dysfunction, abdominal problem or paraplegia was significantly higher in the patient group with open distal technique. Either open distal anastomosis or aortic balloon occlusion technique would be appropriately selected according to the patient's characteristics or the condition of aortic disease to be operated.     

Renal failure after thoracoabdominal aortic surgery

PURPOSE: Renal failure remains a common and morbid complication after complex aortic surgery. This study was performed to identify perioperative factors that contribute to postoperative renal failure. METHODS: The perioperative outcomes of 183 patients who underwent thoracoabdominal aortic surgery with supraceliac clamping were reviewed. During the interval from Jan. 1987 to Nov. 1996, thoracoabdominal aneurysm repair was performed in 154 patients (type I, 49 patients [27%]; type II, 21 patients [11.5%]; type III, 55 patients [30%]; type IV, 29 patients [16%]), suprarenal abdominal aortic aneurysm repair in 17 patients (9%), and visceral/renal revascularization procedures in 12 patients (6.5%). Intraoperative management included thoracoabdominal aortic exposure and clamp-and-sew technique with renal artery cold perfusion whenever the renal arteries were accessible (79% of cases). RESULTS: Relevant clinical features included preoperative hypertension (85%), diabetes mellitus (8%), single functioning kidney (10%), recent intravenous contrast injection (34%), renal insufficiency (creatinine level greater than 1.5 mg/dl; 24%), and emergent operation (19%). Acute renal failure, defined as both a doubling of serum creatinine level and an absolute value greater than 3.0 mg/dl, occurred in 21 patients (11.5%), of whom five required hemodialysis (2.7%). Variables associated with this complication included a preoperative creatinine level greater than 1.5 mg/dl (p = 0.004) and a total cross-clamp time greater than 100 minutes (p = 0.035). The operative mortality risk (within 30 days; 8%) was significantly increased with renal failure (odds ratio, 9.2; 95% confidence interval, 2.6 to 33; p < 0.005). CONCLUSIONS: Renal failure, although uncommon in contemporary practice, greatly increases the risk of early death after thoracoabdominal aortic surgery. The overall incidence of renal failure and dialysis requirement in the present series compare favorably with those reported using other operative techniques, specifically partial left heart bypass and distal aortic perfusion. These data suggest that patients who have preoperative renal insufficiency are prone to postoperative renal failure. Furthermore, regional hypothermic perfusion and minimal clamp times are important elements in the prevention of renal failure after thoracoabdominal aortic surgery.     

Current status of the use of retroperitoneal approach for reconstructions of the aorta and its branches

OBJECTIVE: The objective of this article is to determine whether retroperitoneal approach for aortic surgery has certain physiologic, technical advantages. SUMMARY BACKGROUND DATA: The retroperitoneal approach for abdominal aortic reconstruction classically had been reserved for select patients with either high-risk comorbid disease or specific anatomic problems that preclude the transabdominal approach. With increasing appreciation of the physiologic, anatomic, and technical advantages of the extended posterolateral retroperitoneal approach, the authors have expanded its use for repair of all types of aortic visceral and renal artery disease as well as ruptured abdominal aortic aneurysm and infected aortic grafts. METHODS: From January 1981 to September 1995, 2340 retroperitoneal aortoiliac reconstructions were performed in 2243 patients. Aortic reconstructions accounted for 1756 cases: 1109 for elective abdominal aortic aneurysms, 210 for ruptured and symptomatic aortic aneurysms, 399 for occlusive disease, 18 for infected aortic grafts, and 20 for other indications. Iliofemoral disease was the indication for 584 procedures. As experience was gained, this approach also was used for 417 renal and 50 celiac and superior mesenteric artery reconstructions. RESULTS: The mean age was 67 years with 1590 men and 653 women. Overall mortality was 5.2% for all aortic cases: 2.4% for elective, 12.6% for symptomatic, and 29.0% for ruptured aortic aneurysms. Major complications occurred in 12.5% of the elective procedures and in 38.3% of emergency procedures. Over the past 5 years, the average length of hospital for uncomplicated elective abdominal aortic aneurysms was 6.1 days, intensive care unit stay was 0.7 day, and diet was resumed by postoperative day 1. Five-year graft patency was 99% for aneurysms and 95% for occlusive disease. CONCLUSIONS: The retroperitoneal approach offers certain physiologic advantages associated with minimal disturbance of gastrointestinal and respiratory function, thereby reducing the length of intensive care unit and hospital stay. In addition, its technical advantages and flexibility facilitates visceral and juxtarenal aortic reconstructions without the need for thoracotomy.     

Technical advances in the surgical management of thoracoabdominal aortic aneurysms]

Thoracoabdominal aortic aneurysmectomy ranks among the major cardiovascular surgical procedures. During the last two decades perioperative results have improved to the point that surgery should be discussed in the vast majority of patients seen with a thoracoabdominal aortic aneurysm. This progress is largely attributable to a variety of technical improvements including: aortic reconstruction using the graft inclusion technique, usually with direct reattachment of aortic branches to the prosthetic graft; distal aortic perfusion; selective use of deep hypothermic circulatory arrest in anatomically complex situations; preoperative visualization of arterial blood supply to the spinal cord using selective arteriography of intercostal and lumbar arteries. Current perioperative mortality is around 10% whereas the spinal cord complication rate is between 5% and 20% according to clinical and anatomical conditions. Future efforts should concentrate on the prevention of spinal cord complications.     

Results of autopsy 7 months after successful endoluminal treatment of an infrarenal abdominal aortic aneurysm

PURPOSE: To report the results of a postmortem examination in a patient who died of unrelated causes 7 months following endoluminal treatment of an infrarenal abdominal aortic aneurysm (AAA). METHODS: As part of an FDA Phase I pilot study, a 73-year-old man underwent successful endoluminal exclusion of an infrarenal AAA using a 9-cm-long endograft (Endovascular Grafting System). Seven months later, he succumbed to complications of a spontaneous esophageal rupture. At autopsy, the aorta was dissected in situ by a vascular surgeon and pathologist before being explanted in order to examine the wound healing characteristics at the aorta-endograft interface. Particular attention was also directed to the hooks composing the attachment system at each end of the endograft. RESULTS: Macroscopic and microscopic examination revealed that the graft had completely excluded the aneurysm sac from the circulation and was incorporated into the aortic wall at the proximal neck and distal cuff. A smooth pannus of endothelial cells covered the proximal end of the endograft at the areas of contact with the aorta, while microscopic examination of the distal end of the graft revealed poorly formed, fibrinous pannus. The neointima deep to the endothelium consisted of a collagenous matrix containing myofibroblasts and histiocytes, providing evidence of healing between the endograft and aorta. Both renal arteries were clear of the proximal end of the endograft, but a previously unrecognized right lower pole renal artery with an extremely caudal origin was excluded from the aortic lumen. Each hook of the attachment system was seen protruding through the adventitia of the aorta. There was no evidence of trauma to the aortic wall or the surrounding tissues caused by these hooks. CONCLUSION: There appears to be evidence that an endoluminally placed aortic graft may be incorporated by the host aortic tissue.     

Endoleaks after endovascular graft treatment of aortic aneurysms: classification, risk factors, and outcome

PURPOSE: Incomplete endovascular graft exclusion of an abdominal aortic aneurysm results in an endoleak. To better understand the pathogenesis, significance, and fate of endoleaks, we analyzed our experience with endovascular aneurysm repair. METHODS: Between November 1992 and May 1997, 47 aneurysms were treated. In a phase I study, patients received either an endovascular aortoaortic graft (11) or an aortoiliac, femorofemoral graft (8). In phase II, procedures and grafts were modified to include aortofemoral, femorofemoral grafts (28) that were inserted with juxtarenal proximal stents, sutured endovascular distal anastomoses within the femoral artery, and hypogastric artery coil embolization. Endoleaks were detected by arteriogram, computed tomographic scan, or duplex ultrasound. Classification systems to describe anatomic, chronologic, and physiologic endoleak features were developed, and aortic characteristics were correlated with endoleak incidence. RESULTS: Endoleaks were discovered in 11 phase I patients (58%) and only six phase II patients (21%; p < 0.05). Aneurysm neck lengths 2 cm or less increased the incidence of endoleaks (p < 0.05). Although not significant, aneurysms with patent side branches or severe neck calcification had a higher rate of endoleaks than those without these features (47% vs 29% and 57% vs 33%, respectively), and patients with iliac artery occlusive disease had a lower rate of endoleaks than those without occlusive disease (18% vs 42%). Endoleak classifications revealed that most endoleaks were immediate, without outflow, and persistent (71% each), proximal (59%), and had aortic inflow (88%). One patient with a persistent endoleak had aneurysm rupture and died. CONCLUSIONS: Endoleaks complicate a significant number of endovascular abdominal aortic aneurysm repairs and may permit aneurysm growth and rupture. The type of graft used, the technique of graft insertion, and aortic anatomic features all affect the rate of endoleaks. Anatomic, chronologic, and physiologic classifications can facilitate endoleak reporting and improve understanding of their pathogenesis, significance, and fate.