Open Repair of Pararenal Aortic Aneurysms: Operative Management, Early Results, and Risk Factor Analysis

Surgical treatment of pararenal aortic aneurysms, if compared to open surgical repair of infrarenal aneurysms, is technically more demanding and characterized by problems related to organ ischemia. To better define challenges, risks, and results, we analyzed our experience with the treatment of pararenal aortic aneurysms. Between January 1993 and March 2005, 119 consecutive patients underwent surgery for pararenal aneurysms at our institution. A prospective analysis of results was performed. According to their localization, we treated 85 juxtarenal aneurysms and 34 suprarenal aneurysms. One hundred and three patients underwent primary repair of an atherosclerotic aneurysm, four patients underwent surgical repair of an anastomotic pseudoaneurysm, and eight patients underwent correction of an aneurysm of the pararenal aorta proximal to a previous infrarenal anastomosis. Four patients underwent emergency operation for a ruptured aneurysm. In the juxtarenal aneurysm group, the 30-day mortality rate was 4.7% (4/85) including three patients with ruptured aneurysm. In the suprarenal aneurysm group, the 30-day mortality rate was 2.9% (1/34). Preoperative renal insufficiency was present in 16 patients, respectively in 7 patients with juxtarenal aneurysms and in 9 patients with suprarenal ones. In 22 patients, we registered a transient increase in creatinine levels with return to baseline levels by discharge. Four patients required long-term dialysis. In three patients, a short period of dialysis was required. Clamping time longer than 30 min was associated with a higher risk of transient postoperative deterioration of renal function (p = 0.0073). Preoperative renal insufficiency was associated with a higher risk of persistent postoperative deterioration of renal function (p < 0.0001). Morbidity and mortality of elective surgery for pararenal aneurysms is acceptable. One of the main risks of this surgery is renal morbidity. Preoperative renal insufficiency and long periods of renal ischemia are associated with a higher risk of postoperative deterioration of renal function that is often, but not always, reversible. Nowadays, pararenal aneurysm repair is a safe procedure, especially if performed electively.     

Pararenal aortic aneurysms: the future of open aortic aneurysm repair

PURPOSE: As endovascular stent graft repair of infrarenal abdominal aortic aneurysms (AAAs) becomes more common, an increasing proportion of patients who undergo open operation will have juxtarenal aneurysms (JR-AAAs), which necessitate suprarenal crossclamping, suprarenal aneurysms (SR-AAAs), which necessitate renal artery reconstruction, or aneurysms with associated renal artery occlusive disease (RAOD), which necessitate repair. To determine the current results of the standard operative treatment of these patterns of pararenal aortic aneurysms, we reviewed the outcome of 257 consecutive patients who underwent operation for JR-AAAs (n = 122), SR-AAAs (n = 58), or RAOD (n = 77). METHODS: The patients with SR-AAAs and RAOD were younger (67.5 +/- 8.8 years) than were the patients with JR-AAAs (70.5 +/- 8.3 years), and more patients with RAOD were women (43% vs 21% for JR-AAAs and SR-AAAs). The patient groups were similar in the frequency of coronary artery and pulmonary disease and in most risk factors for atherosclerosis, except hypertension, which was more common in the RAOD group. Significantly more patients with RAOD had reduced renal function before surgery (51% vs 23%). Supravisceral aortic crossclamping (above the superior mesenteric artery or the celiac artery) was needed more often in patients with SR-AAAs (52% vs 39% for RAOD and 17% for JR-AAAs). Seventeen patients (7%) had undergone a prior aortic reconstruction. The most common renal reconstruction for SR-AAA was reimplantation (n = 37; 64%) or bypass grafting (n = 12; 21%) and for RAOD was transaortic renal endarterectomy (n = 71; 92%). Mean AAA diameter was 6.7 +/- 2.1 cm and was larger in the JR-AAA (7.1 +/- 2.1 cm) and SR-AAA (6.9 +/- 2.1 cm) groups as compared with the RAOD group (5.9 +/- 1.7 cm). RESULTS: The overall mortality rate was 5.8% (n = 15) and was the same for all the groups. The mortality rate correlated (P <.05) with hematologic complications (bleeding) and postoperative visceral ischemia or infarction but not with aneurysm group or cardiac, pulmonary, or renal complications. Renal ischemia duration averaged 31.6 +/- 21.6 minutes and was longer in the SR-AAA group (43.6 +/- 38.9 minutes). Some postoperative renal function loss occurred in 104 patients (40.5%), of whom 18 (7.0%) required dialysis. At discharge or death, 24 patients (9.3%) still had no improvement in renal function and 11 of those patients (4.3%) remained on dialysis. Postoperative loss of renal function correlated (P <.05) with preoperative abnormal renal function and duration of renal ischemia but not with aneurysm type, crossclamp level, or type of renal reconstruction. CONCLUSION: These results showed that pararenal AAA repair can be performed safely and effectively. The outcomes for all three aneurysm types were similar, but there was an increased risk of loss of renal function when preoperative renal function was abnormal. These data provide a benchmark for expected treatment outcomes in patients with these patterns of pararenal aortic aneurysmal disease that currently can only be managed with open repair.     

Results of open pararenal abdominal aortic aneurysm repair: Tabular review of the literature

Open surgical repair of complex abdominal aortic aneurysms requires more extensive dissection and aortic clamping above the renal or mesenteric arteries. Although results of open surgical series have shown variation, morbidity and mortality is higher compared with infrarenal aortic aneurysm repair. Potential complications include renal insufficiency, mesenteric ischemia, multisystem organ failure, and death. Although endovascular treatment with fenestrated and branched endografts might potentially decrease the risk of complications and mortality, its role is not yet defined and the technology is not widely available. Issues related to durability of the procedure and secondary interventions might limit its application to patients with higher risk or those with hostile anatomy. This article summarizes the clinical results of open surgical repair of pararenal abdominal aortic aneurysms to provide a benchmark for comparison with results of endovascular treatment, using fenestrated and branched techniques.     

Open repair of pararenal aortic aneurysms

Surgical treatment of pararenal aortic aneurysms, if compared to open repair of infrarenal aneurysms, is characterized by more technical difficulties and haemodynamic problems. Since endovascular repair has become feasible in most cases of infrarenal aneurysms, surgical treatment of pararenal aneurysms is a matter of great interest for vascular surgery. Detection of pararenal aneurysms needs a careful preoperative diagnosis, assessment of cardiac, renal and pulmonary status of the patient and planning of the surgical intervention. The surgeon needs to face an extended proximal aorta exposure, to manage the left renal vein and to choose an appropriate clamping site. Then a skilled and quick reconstruction of the visceral arteries is fundamental to minimize organ disfunction. Coupled intraoperative selective perfusion of visceral arteries and systemic administration of nephroprotective drugs optimizes organ protection during ischemia. To better define challenges, risks and results, we reviewed our experience with the treatment of pararenal aortic aneurysms. In the period between January 1993 and May 2003, 98 consecutive patients underwent surgery for pararenal aneurysms at our Institution. We treated 98 pararenal aneurysms, divided in 68 juxtarenal and 30 pararenal ones. In the juxtarenal aneurysms group, the 30 days mortality rate was 5.8% (4/68); 3 of these patients underwent urgent operation for ruptured aneurysm. In the suprarenal aneurysms group, the 30 days mortality rate was 3.3% (1/30). In conclusion pararenal aneurysm repair is a safe procedure, especially if performed electively, and represents an interesting field of research to improve surgical and anesthesiologic techniques.     

Successful endovascular repair of juxtarenal and suprarenal aortic aneurysms with a branched stent graft

This case report describes a new technique for repairing pararenal aortic aneurysms with a transluminally placed triple-branched stent graft with sidearms extending into the superior mesenteric artery and renal arteries. Endovascular repair with the branched stent graft was attempted in two patients with a pararenal aortic Aneurysm. Stent grafting was technically successful in both patients. Although postoperative transient renal function impairment and paralytic ileus occurred in patient 2, these complications were gradually resolved in the perioperative period. A substantial shrinkage of the aneurysm was revealed by means of computed tomographic measurements in patient 1. In both patients, complete exclusion of the aneurysm and patency of the bilateral renal arteries and the superior mesenteric artery were confirmed by means of follow-up computed tomographic images at 2 years. This minimally invasive approach for pararenal aortic aneurysms appears to be a viable therapeutic option for patients who are at high risk for open surgery.     

Endovascular stent-graft repair of pararenal and type IV thoracoabdominal aortic aneurysms with adjunctive visceral reconstruction

OBJECTIVE: Pararenal and type IV thoracoabdominal aortic aneurysms (TAAA) are not currently considered as indications for endovascular repair given unfavorable neck anatomy or aneurysm involvement of the visceral vessels. Open repair of these aneurysms is associated with significant morbidity and mortality, particularly postoperative renal dysfunction. In selective high-risk patients, debranching of the visceral aorta to improve the proximal neck region can be used to facilitate endovascular exclusion of the aneurysm. METHODS: Between October 2000 and July 2003, 10 patients were treated with open visceral revascularization and endovascular repair of pararenal and type IV TAAAs at a single institution. Patient demographics and procedural characteristics were obtained from medical records. RESULTS: Overall 13 visceral bypasses were performed in 10 patients: 6 patients with a single iliorenal bypass, 3 with a hepatorenal bypass, and 1 patient with complete visceral revascularization. Juxtarenal aneurysms occurred in 5 patients (50%), suprarenal aneurysms in 3 patients (30%), and type IV TAAAs in 2 patients (20%). All patients had successful endovascular aneurysm exclusion. Mean follow-up was 8.7 months. There were no perioperative deaths, neurologic deficits coagulopathies, or renal dysfunction. Follow-up spiral computed tomography scans demonstrated patency of all bypass grafts with only one patient requiring a secondary intervention for late type I leak which was sealed with placement of a proximal cuff. CONCLUSION: These initial results suggest that are similar to infrarenal AAA endovascular repair. This combined approach to repair of pararenal and type IV TAAAs reduces the morbidity and mortality of open repair, and represents an attractive option in high-risk patients while endoluminal technology continues to evolve.     

Management of pararenal aneurysms of the abdominal aorta

The operative treatment of 77 patients with atherosclerotic aneurysms of the pararenal aorta (54 juxtarenal and 23 suprarenal) is analyzed. Repair of these complex lesions is formidable because of difficult exposure, renal ischemia and myocardial strain as a result of proximal aortic occlusion, and associated renal atherosclerosis with secondary renal functional impairment. Nineteen (25%) patients were normotensive with normal renal function. Sixteen patients (21%) had hypertension alone and 42 (54%) were hypertensive with abnormal renal function. There were multiple renal arteries in 22% of patients. Aortic reconstruction involved infrarenal graft in 27 patients (35%), infrarenal graft plus pararenal aortic endarterectomy (TEA) in 26 (34%), and infra- and pararenal aortic graft in 24 (31%). Twenty-two patients (30%) had normal renal arteries and therefore no renal reconstruction. Of the 55 patients who required combined aortic and renal artery repair, 24 required renal artery repair because of involvement of the renal arteries by the aneurysm and 31 because of atherosclerotic renal artery disease. TEA was the most common technique of renal artery repair (54 of 93 arteries, 58%), followed by reimplantation (18 arteries) and prosthetic graft (13). The perioperative mortality rate was 1.3%. The perioperative morbidity rate was 28% and consisted principally of renal insufficiency (23%). This was usually transient (44%) and (89%) mild. Renal morbidity was adversely affected by renal ischemia status, severity of renal artery disease and extent of renal revascularization. Following reconstruction, hypertension was cured or improved in 77% of patients and abnormal renal function was cured or improved in 46% and stabilized in an additional 39% of patients. These results show that combined aortic aneurysm repair and renal artery reconstruction can be performed with minimal mortality and an acceptable morbidity. Aggressive intraoperative monitoring is necessary to minimize myocardial complications. Careful attention must be paid to the technical details of the reconstruction, especially in minimizing renal ischemia, to reduce the subsequent incidence of renal function deterioration.     

Hybrid procedures as a combined endovascular and open approach for pararenal and thoracoabdominal aortic pathologies

OBJECTIVES: to report our experience with hybrid vascular procedures in patients with pararenal and thoracoabdominal aortic pathologies. METHODS: 68 patients were treated for thoracoabdominal aortic pathologies between October 1999 and February 2004; 19 patients (16 men; mean age 68, range 40-79) with high risk for open thoracoabdominal repair were considered to be candidates for combined endovascular and open repair. Aortic pathologies included five thoracoabdominal Crawford I aneurysms, one postdissection expanding aneurysm, three symptomatic plaque ruptures (Crawford IV), five combined thoracic descending and infrarenal aneurysms with a healthy visceral segment, three juxtarenal or para-anastomotic aneurysms, and two patients with simultaneous open aortic arch replacement and a rendezvous maneuver for thoracic endografting. Commercially available endografts were implanted with standardized endovascular techniques after revascularization of visceral and renal arteries. RESULTS: Technical success was 95%. One patient developed a proximal type I endoleak after chronic expanding type B dissection and currently is waiting conversion. Nine patients underwent elective, five emergency and five urgent (within 24 h) repair. 17 operations were performed simultaneously, and 2 as a staged procedure. Postoperative complications include two retroperitoneal hemorrhages, and one patient required long-term ventilation with preexisting subglottic tracheal stenosis. Thirty-day mortality was 17% (one multiple organ failure, one secondary rupture after open aortic arch repair, one myocardial infarction). Paraplegia or acute renal failure were not observed. Total survival rate was to 83% with a mean follow-up of 30 months. CONCLUSIONS: Midterm results of combined endovascular and open procedures in the thoracoabdominal aorta are encouraging in selected high risk patients. Staged interventions may reduce morbidity.     

Factors affecting outcomes of open surgical repair of pararenal aortic aneurysms: a 10-year experience

PURPOSE: Few large series document surgical outcomes for patients with pararenal abdominal aortic aneurysms (PAAAs), defined as aneurysms including the juxtarenal aorta or renal artery origins that require suprarenal aortic clamping. No standard endovascular alternatives presently exist; however, future endovascular branch graft repairs ultimately must be compared with the gold standard of open repair. To this end, we present a 10-year experience. METHODS: Between 1993 and 2003, 3058 AAAs were repaired. Perioperative variables, morbidity, and mortality were retrospectively assessed. Renal insufficiency was defined as a rise in the concentration of serum creatinine by > or = 0.5 mg/dL. Factors predicting complications were identified by multivariate analyses. Morbidity and 30-day mortality were evaluated with multiple logistic regression analysis. RESULTS: Of a total of 3058 AAA repairs performed, 247 were PAAAs (8%). Mean renal ischemia time was 23 minutes (range, 5 to 60 minutes). Cardiac complications occurred in 32 patients (13%), pulmonary complications in 38 (16%), and renal insufficiency in 54 (22%). Multivariate analysis associated myocardial infarction with advanced age (P = .01) and abnormal preoperative serum creatinine (>1.5 mg/dL) (P = .08). Pulmonary complications were associated with advanced age (P = .03), renal artery bypass (P = .02), increased mesenteric ischemic time (P = .01), suprarenal aneurysm repair (P < .0008), and left renal vein division (P = .01). Renal insufficiency was associated with increased mesenteric ischemic time (P = .001), supravisceral clamping (P = .04), left renal vein division (P = .04), and renal artery bypass (P = .0002), but not renal artery reimplantation or endarterectomy. New dialysis was required in 3.7% (9/242). Abnormal preoperative serum creatinine (>1.5 mg/dL) was predictive of the need for postoperative dialysis (10% vs 2%; P = .04). Patients with normal preoperative renal function had improved recovery (93% vs 36%; P = .0002). The 30-day surgical mortality was 2.5% (6/247) but was not predicted by any factors, and in-hospital mortality was 2.8% (7/247). Median intensive care and hospital stays were 3 and 9 days, respectively, and longer stays were associated with age at surgery (P = .007 and P = .0002, respectively) and any postoperative complication. CONCLUSIONS: PAAA repair can be performed with low mortality. Renal insufficiency is the most frequent complication, but avoiding renal artery bypass, prolonged mesenteric ischemia time, or left renal vein transection may improve results.     

Critical Analysis of Outcome Determinants Affecting Repair of Intact Aneurysms Involving the Visceral Aorta

Visceral (mesenteric and/or renal) ischemia/reperfusion phenomena likely contribute to the greater operative risk associated with pararenal and lower thoracoabdominal aortic aneurysm (TAA) repair. To differentiate the relative adverse effects of aortic clamp level, visceral ischemic duration, and various pre- and perioperative factors shared with infrarenal aneurysm patients, a comparative analysis of early and late outcomes after open repair of intact infrarenal and visceral aortic aneurysms was undertaken. A retrospective review of our university experience from 1993-1999/2002 revealed 549 patients (mean age 70 ± 8 years, 11% female) undergoing open repair of intact, degenerative aneurysms of the infrarenal (n = 391, 71%), juxtarenal (n = 78, 14%), suprarenal (n = 35, 7%), and type IV (n = 40, 7%) and type III (n = 5, 1%) TAA segments. All pararenal aneurysms required suprarenal (SR) or supravisceral (SV, above celiac or superior mesenteric artery) clamp placement. Concomitant renal reconstruction was done in 30% of visceral aortic and 3% of open infrarenal aneurysm repairs. Thirty-day adverse outcomes [death, renal failure (creatinine 2 × baseline or new dialysis), visceral (bowel, hepatic, renal, spinal cord, multiple organ dysfunction), and nonvisceral (cardiac, pulmonary, procedural) complications] were analyzed relative to patient and operative factors using univariate comparisons and multivariate stepwise logistic regression. Perioperative mortality rates varied significantly between aneurysm locations (infrarenal 2.1%, juxtarenal 2.6%, suprarenal 11.4%, TAA 13.3%; p < 0.01) and for clamp locations (infrarenal 2.1%, SR 3.0%, SV 10.8 %; p < 0.01) but were not different between juxtarenal (1.8% vs. 4.4 %) and SR (9.1% vs. 12.5%) aneurysms requiring SR or SV clamping, respectively. Visceral ischemic time (VIT) during SR or SV clamping, and not clamp location, was the only independent predictor of operative mortality [odds ratio (OR) = 10.8, 95% confidence interval (CI) 4-29]. Sensitivity analyses revealed VIT > 32 min to be the strongest predictor of early death. Visceral complication or renal failure affected 34% and 23% of visceral aortic (5% dialysis) and 7% and 5% (1% dialysis) of infrarenal repairs, respectively. VIT > 32 min, SV clamp placement, diabetes, and inflammatory aneurysm repair were each predictive of visceral complications and/or renal failure. Five-year survival rate was similar after visceral aortic (70%) and infrarenal (75%) repairs but negatively impacted only in patients with prior infrarenal abdominal aortic aneurysm repair and recurrent aneurysms (OR = 2.8, 95% CI 1.2-6.9). The high incidence of early adverse outcomes following repair of pararenal and lower thoracoabdominal aneurysms is primarily associated with excessive periods of renal and/or gut ischemia during visceral aortic clamp placement. However, nearly equivalent early and late survival was seen for visceral aortic and infrarenal repairs when VIT < 32 min was achieved.Presented at the Twenty-eighth Annual Meeting of the Southern Association for Vascular Surgery, Rio Grande, Puerto Rico, January 14-17, 2004.     

Endovascular treatment of abdominal aortic aneurysms: is there a benefit regarding postoperative outcome?

BACKGROUND AND OBJECTIVE: The endovascular treatment of abdominal aortic aneurysms has raised great interest amongst vascular surgeons. The aim of this study was to compare the postoperative morbidity and mortality rates of endovascular treatment with those of open surgery, from the anaesthesiologist's standpoint. METHODS: From January 1997 to June 2000, 425 consecutive patients with abdominal aortic aneurysms were referred for regular surgery. Thirty-nine patients who needed a visceral or renal artery revascularization, or a nephrectomy were excluded. The remaining 386 patients were studied in a prospective manner. Aneurysms were evaluated with spiral computerized tomography scanning and calibrated aortography. After informed consent, only those patients with a suitable vascular anatomy underwent endovascular treatment (n = 193). All other patients underwent open surgery and are considered as a control group (n = 193). Endovascular treatment was performed by a femoral or an iliac retroperitoneal route. All stent-grafts were made to measure using auto-expandable stainless-steel stents covered with a standard polyester prosthetic graft. RESULTS: Six patients in the endovascular treatment group needed to be converted to the open surgical technique (during the same operation) because of rupture of the iliac bifurcation (1 patient), a large endoleak (2 patients), or technical problems (3 patients). CONCLUSION: The amount of bleeding and the need for blood products were significantly lower in the endovascular treatment group. Despite the absence of significant differences regarding cardiac complications and mortality, there was a lesser incidence of pneumonia, acute respiratory and renal failure. Patients in the endovascular treatment group spent less time in the intensive care unit and in the Hospital.     

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??Prevention and treatment of abdominal aortic aneurysm open repair complication ZHAO Ji-chun. Division of Vascular Surgery, West China Hospital, Sichuan University, Chengdu610041, China
Abstract Open repair with graft placement has been utilized to treat abdominal aortic aneurysms(AAAs) and is the standard procedure. The major risks in open AAA repair are still the risk of massive blood ,persistant unclamping hypotension,sigmoid colon ischemia and distal artery embolization during open AAA repairs but perioperative cardiac events and renal or respiratory failure. Elective open surgical AAA repair is a complex procedure with a 30-day mortality of 3%~5% and a complication rate of 15% to 20%.     

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.     

Surgical repair of thoracoabdominal aortic aneurysms

Morbidity and mortality following thoracoabdominal aortic aneurysm (TAAA) repair are tremendous. Preoperative assessment is essential in detecting cardiac and pulmonary risk factors in order to reduce cardiopulmonary complications. Paraplegia and renal failure are main determinants of postoperative mortality and therefore gained substantial attention during the last decades. Left heart bypass, cerebrospinal fluid (CSF) drainage and epidural cooling have significantly reduced paraplegia rate, however, this dreadful event still occurs in up to 25% of patients undergoing type II repair. Renal failure has been partly prevented by means of retrograde aortic perfusion and cooling but renal failure still remains a significant problem. We have evaluated the effects of protective measures aiming for reduction of paraplegia and renal failure. Monitoring motor evoked potentials (MEPs) is an accurate technique to assess spinal cord integrity during TAAA repair, guiding surgical strategies to prevent paraplegia. Selective volume- and pressure controlled perfusion is a technique to continuously perfuse the kidneys during aortic cross clamping and subsequent circulatory exclusion In patients with atherosclerotic thoracoabdominal aortic aneurysms, blood supply to the spinal cord depends on a highly variable collateral system. In our experience, monitoring MEPs allowed detection of cord ischemia, guiding aggressive surgical strategies to restore spinal cord blood supply and reduce neurologic deficit: overall paraplegia rate was less than 3%. We believe that these protective measures should be included in the surgical protocol of TAAA repair, especially in type II cases. Renal and visceral ischemia can be reduced significantly by continuous perfusion during aortic cross clamping in TAAA repair. Not only sufficient volume flow but also adequate arterial pressure appears to be essential in maintaining renal function.Obviously, endovascular modalities have been successfully applied in TAAA patients, the majority of which as part of hybrid procedures. Technological innovation will eventually cause a shift from open to minimal invasive surgical repair. At present, however, open surgery is considered the gold standard for TAAA repair, especially in (relatively) young patients and patients suffering from Marfan's disease.     

Hybrid-procedures for the treatment of thoracoabdominal aortic aneurysms and dissections.

AIM: The conventional open repair of thoracoabdominal aneurysms and dissections remains complex and demanding and is associated with significant morbidity and mortality. We present our experience of hybrid open and endovascular treatment of thoracoabdominal aneurysms and dissections. METHODS: Within an experience of 226 aortic stent-grafts between 1998 and April 2006, 6 of the patients (median age 60 years, range 35 to 68 years) with thoracoabdominal aneurysms (Crawford type I, II, III, and V) were treated with a combined endovascular and open surgical approach. Five men and one woman, with median aneurysm diameter of 75 mm (range 70-100 mm), received revascularization of the renal arteries, the superior mesenteric artery, and the coeliac trunk accomplished via transperitoneal bypass grafting. Aneurysmal exclusion was then performed by stent-graft deployment. RESULTS: The entire procedure was technically successful in all patients. The patients were discharged a median of 9 days after the operation, while the postoperative studies revealed the patency of the vessels and no evidence of type I endoleak or secondary rupture of the aneurysm. During follow up (1 to 22 months) spiral-CT scanning revealed distinct shrinkage of the aneurysm, no graft migration or endoleak and patency of all revascularised vessels, except one renal artery in two patients. No patient experienced any temporary or permanent neurological deficit, and no dialysis was necessary. CONCLUSION: The combined endovascular and open surgical approach is feasible, without cross clamping of the aorta and with minimized ischemia time for renal and visceral arteries, and seems to be an appropriate strategy for patients with a thoraco-abdominal aortic aneurysm or dissection.     

Left flank retroperitoneal exposure: a technical aid to complex aortic reconstruction

Over the last 5 years an extended left flank retroperitoneal approach was used in 85 of 531 (16%) aortic reconstructions deemed technically complex. Abdominal aortic aneurysm repair was performed in 70 patients (82%), bypass of aortoiliac occlusive disease was performed in 11 (13%), and aortic endarterectomy for mesenteric and/or renovascular disease was performed in 4 (5%). Indications for use of this approach included a "hostile" abdomen (43 patients), juxta/suprarenal abdominal aortic aneurysm (35), large (greater than 10 cm) abdominal aortic aneurysm (12), extreme obesity (10), associated renal and/or visceral artery stenosis requiring endarterectomy (9), inflammatory abdominal aortic aneurysm (2), and horseshoe kidney (2). Suprarenal or supraceliac aortic clamping, averaging 31 minutes, was required in 43 patients (50%). Postoperative recovery was rapid (average length of stay, 10.2 days), and morbidity was minimal despite the complex nature of these reconstructions. The perioperative mortality rate in elective operations was 1.2%. This approach facilitated proximal abdominal aortic exposure and anastomosis, especially in large, pararenal aneurysms or in situations unfavorable to a transabdominal approach. Whereas a left flank retroperitoneal approach can be used in most aortic reconstructions, it seems especially suited to those that pose significant technical challenges.     

Aorto-Left Renal Artery Bypass as an Adjunct to Suprarenal Abdominal Aortic Aneurysm Repair

Renal ischemia remains a vexing issue in the repair of suprarenal abdominal aortic aneurysms (SR-AAAs). Multiple reconstruction methods have been described, including fish-mouth anastomoses, renal artery reimplantation, and aortorenal interposition grafts. We present an alternative method of SR-AAA repair that minimizes renal ischemia time. We describe our approach in two patients with SR-AAAs. Both patients had normal preoperative renal function. Maximal aneurysm diameters were 6.0 and 7.4 cm. In each case, the abdominal aorta was exposed via the retroperitoneal approach and the supraceliac aorta was dissected from the surrounding tissue. A partially occluding side-biting aortic clamp was placed at this level to facilitate placement of a synthetic 6 mm interposition graft that was sewn in an end-to-side fashion to the suprarenal aorta first. These grafts were then sewn end-to-end to the left renal artery, completing the aorto-left renal bypass. Left renal ischemia times were 12 and 14 min. The aneurysm was then repaired with a beveled proximal anastomosis, accommodating the right renal artery orifice. Both patients had minimal postoperative renal dysfunction, with peak creatinine levels of 1.9 and 1.4 mg/dl. At discharge, both patients had a creatinine level of 1.1 mg/dl. Urinary output remained normal throughout the hospital stays, and neither patient required dialysis. Retroperitoneal aortic exposure with preliminary aorto-left renal artery bypass is an effective method of treating SR-AAAs. Proximal anastomosis can be done with less urgency and minimal right renal ischemia, by revascularizing the left kidney first.Presented at the Twenty-second Annual Meeting of the Southern California Vascular Surgery Society, La Jolla, CA, April 30-May 2, 2004.     

Aortic reconstruction in patients with functioning renal allografts

Patients with functioning renal allografts requiring aortic reconstruction pose a considerable challenge to the vascular surgeon. A variety of strategies for renal allograft preservation during intervention have been described including hypothermia, indwelling shunts, cold renal perfusion, axillofemoral bypass, and endovascular stent-grafting. Reported here are two cases of successful aortic reconstruction utilizing standard open surgical techniques designed simply to minimize warm renal ischemia. The first case was that of a 55 year-old patient with a functional renal allograft originating from the right external iliac artery, who presented acutely with large symptomatic aortic and bilateral iliac artery aneurysms. He was treated with aorto-right femoral/left iliac bypass grafting. The right femoral anastomosis was performed first so that warm renal ischemia was limited to the 34 min required to perform the proximal end-to-end aortic anastomosis. The second case was that of a 44-year-old patient also with a transplanted kidney originating from the right external iliac artery. He presented with worsening hypertension, decreasing renal function, claudication, and severe aortoiliac occlusive disease. He was treated with aorto-left femoral bypass grafting via a retroperitoneal approach, followed by femorofemoral crossover bypass for retrograde perfusion of the kidney (total warm ischemia time 20 min). Both patients recovered uneventfully without a decrement in renal function and remain well on follow-up. It is concluded that standard open surgery without adjunctive shunts or bypasses remains a viable treatment option for these patients, provided warm renal ischemia can be minimized.     

Emergency endovascular treatment for ruptured abdominal aortic aneurysm and the risk of spinal cord ischemia

BACKGROUND: Spinal cord ischemia is a rare complication after open surgical repair for ruptured abdominal aortic aneurysms (rAAA). The use of emergency endovascular aortic aneurysm repair (eEVAR) is increasing, and paraplegia has been observed in a few patients. The objective of this study was to assess the incidence and pathogenesis of spinal cord ischemia after eEVAR in greater detail. METHODS: This was a retrospective analysis of patients who had eEVAR for rAAA in three hospitals in The Netherlands and Belgium during a 3-year study period that ended in February 2004. The use of aortouniiliac devices combined with a femorofemoral crossover bypass was the preferred technique. Patients with postoperative symptoms of spinal cord ischemia were identified and the influence of potential risk factors was assessed. These factors included the presence of common iliac artery aneurysms necessitating device limb extension to the external iliac artery with associated overlapping the hypogastric artery, the prolonged interruption of bilateral hypogastric artery arterial inflow during the procedure (defined "functional aortic occlusion time" >30 minutes), and the occurrence of preoperative hemodynamic shock. RESULTS: Thirty-five patients were treated by EVAR and they constituted the study group. The first-month mortality in the study group with EVAR was 23%. Four patients (11.5%) with EVAR developed paraplegia postoperatively; the unilateral or bilateral hypogastric artery in all four patients became occluded during the procedure. In the other 31 patients who did not have paraplegia, the unilateral or bilateral hypogastric arteries became occluded in 14 patients (45%). This constituted a significant difference in the prevalence of hypogastric artery occlusion in patients with or without paraplegia (P = .04). The functional aortic occlusion time was prolonged in all four patients with paraplegia and in five without spinal cord ischemia (P = .0003). All four patients with spinal cord ischemia presented with hemodynamic shock. This factor did not reach a significant difference from nonparaplegic patients. CONCLUSION: Emergency EVAR continues to be a promising approach to reduce the high mortality of rAAA, but the incidence of spinal cord ischemia after endovascular treatment of rAAA was worrisome. Although the pathogenesis is most likely multifactorial, interruption of the hypogastric artery inflow appeared to have significant influence. In patients with aneurysmatic common iliac arteries, any effort should be made to minimize hypogastric occlusion time during the procedure and to maintain hypogastric artery inflow afterwards, either by the use of a bell-bottom iliac extension or by electing open repair.     

Ancillary techniques to facilitate endovascular repair of aortic aneurysms.

PURPOSE: The ability to treat abdominal aortoiliac aneurysms and thoracic aortic aneurysms may be limited by coexisting arterial disease. Device deployment may be impaired by occlusive disease and tortuosity of the arteries used to access the aneurysm or by suitability of the implantation sites. In this study we describe the auxiliary procedures performed to circumvent these obstacles and thereby enable endovascular aneurysm repair. PATIENTS AND METHODS: Between January 1, 1993, and December 31, 1999, 390 patients treated for aneurysm of the aorta with endovascular devices were entered prospectively in a vascular registry. Fifty (12%) of the 390 patients required adjunctive surgical techniques to (1) create or extend the length of the proximal or distal device implantation site or (2) permit device navigation through diseased iliac arteries. Auxiliary techniques used to extend or enhance implantation sites were elephant trunk graft (n = 2), the construction of renovisceral bypass grafts (n = 1), and subclavian artery transposition (n = 2). Plication of the common iliac artery at its bifurcation was performed in conjunction with femorofemoral bypass graft in nine patients to allow preservation of pelvic circulation by avoiding internal iliac artery sacrifice. Construction of a bypass graft to transpose the internal iliac artery orifice was performed in one patient. The auxiliary techniques used to facilitate device navigation were iliac artery angioplasty or stenting (n = 8), external iliac artery endovascular endarterectomy or straightening (n = 14), endoluminal iliofemoral bypass conduit (n = 5), and the construction of an open iliofemoral bypass conduit (n = 8). RESULTS: Successful deployment of the endovascular devices was achieved in 49 (98%) of 50 patients. Auxiliary techniques were successful in providing access for endovascular device deployment in all 35 patients (100%). Mean follow-up for techniques to facilitate device navigation is 26 months for endovascular procedures and 42 months for the open bypass graft construction patients; no occlusions were observed at this moment. There were five patients with incisional hematomas that did not necessitate intervention. Fourteen (94%) of 15 patients underwent successful device implantation after the auxiliary maneuvers to enhance implantation site. Mean follow-up for implantation site manipulation is 28 months. One of the subclavian transpositions had a new onset of Horner's syndrome, two of nine patients who had common iliac artery ligated had retroperitoneal hematomas that did not necessitate interventions, and no colon ischemia was seen. The patient who underwent nonanatomic bypass grafting of viscero-renal arteries had a retroperitoneal hematoma that necessitated reexploration. CONCLUSIONS: Significant coexisting arterial disease may be encountered in patients with aortic or iliac aneurysms. Identification of coexisting arterial diseases is essential to help tailor the appropriate supplemental surgical procedure to allow the performance of endovascular aneurysm repair in patients who would otherwise require open surgical repair.