Fenestrated and branched stent-grafting after previous surgery provides a good alternative to open redo surgery.

OBJECTIVE: To present our experience using fenestrated and branched endoluminal grafts for Para-anastomotic aneurysms (PAA) following prior open aneurysm surgery, and after previous endovascular aneurysm repair (EVAR) complicated by proximal type I endoleak. METHODS: Fenestrated and/or branched EVAR was performed on eleven patients. Indications included proximal type I endoleak after EVAR and short infrarenal neck (n=4), suprarenal aneurysm after open AAA (n=4), distal type I endoleak after endovascular TAA (n=1), proximal anastomotic aneurysm after open AAA (n=1), and an aborted open AAA repair due to bleeding around a short infrarenal neck. RESULTS: The operative target vessel success rate was 100% (28/28) with aneurysm exclusion in all patients. Mean hospital stay was 6.0 days (range 2-12 days, SD 3.5 days). Thirty day mortality was 0%. All cause mortality during 18 months mean follow-up (range 5-44 months, SD 16.7 months) was 18% (2/11) with no deaths from aneurysm rupture. Cumulative visceral branch patency was 96% (27/28) at 42 months. Average renal function remained unchanged during the follow-up period. CONCLUSIONS: Our report highlights the potential of fenestrated and branched technology to improve re-operative aortic surgical outcomes. The unique difficulties of increased graft on graft friction hindering placement, short working distance, and increased patient co-morbidities should be recognized.     

Repair of juxtarenal para-anastomotic aortic aneurysms after previous open repair with fenestrated and branched endovascular stent grafts

Three patients with juxtarenal para-anastomotic aortic aneurysms after previous open abdominal aortic aneurysm repair were treated with custom-designed fenestrated and branched Zenith endovascular stent grafts. Six renal arteries and two superior mesenteric arteries were targeted for incorporation by graft fenestrations and branches. The fenestration/renal ostium interface was secured with balloon-expandable Genesis stents (n = 5) or Jostent stent grafts (n = 1). Completion angiography demonstrated no endoleaks and antegrade perfusion in all target vessels. During follow-up, one patient developed asymptomatic renal artery occlusion and underwent further endovascular intervention for type I distal endoleak. Computed tomography at 12 months demonstrated complete aneurysm exclusion in all patients with antegrade perfusion in the remaining target vessels. Fenestrated and branched endovascular stent grafts may be an acceptable alternative to conventional open repair in this group of patients.     

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.     

Hybrid approach to thoracoabdominal aortic aneurysms in patients with prior aortic surgery

OBJECTIVE: The hybrid approach to the repair of thoracoabdominal aortic aneurysm (TAAA), consisting of visceral aortic debranching with retrograde revascularization of the splanchnic and renal arteries and aneurysm exclusion using stent grafts, has been previously described and may be considered particularly appealing in high-risk patients, especially those who have undergone prior aortic surgery. This study analyzed prospectively recorded data of a series of high-risk patients with prior aortic surgery who underwent hybrid TAAA repair at our institute and contrasted the outcomes with those of a similar group of patients who underwent conventional open TAAA repair. METHODS: Between 2001 and 2006, 13 patients (12 men) with a median age of 69.6 years (range, 35 to 82 years) underwent one-stage hybrid repair of TAAA (7 type I, 2 type II, 2 type IV, and 2 aneurysms of the visceral aortic patch). These patients, the hybrid group, had a history of aortic surgery (30.7% ascending, 30.7% descending, 46.1% abdominal aortic repair, and 15.4% redo TAAA) and were at high risk for open repair. The criteria used to define these patients as high risk and to indicate the need for hybrid treatment were American Society of Anesthesiologists (ASA) class 3 or 4 associated with a preoperative forced expiratory volume in 1 second (FEV1)<50%. In all cases, we accomplished partial or total visceral aortic debranching through (1) a previous visceral artery retrograde revascularization with synthetic grafts (single bypass, customized Y or bifurcated grafts), and (2) aortic endovascular repair with one of three different commercially produced stent grafts (Cook, W.L. Gore & Assoc, and Medtronic). We analyzed the results and compared the outcomes of the hybrid group with those of a similar group of 29 patients (25 men) with a median age 65.3 years (range, 58 to 79) selected from our overall series of 246 TAAA repairs between 1988 and 2005. These 29 patients, the conventionally treated group, were selected for having had aortic surgery (22% ascending, 38% descending, 42% abdominal aortic repair, and 10.3% redo TAAA), an ASA 3 or 4, a preoperative FEV1<50%, and a conventional open repair of TAAA (10 type I, 5 type II, 4 type III, 7 type IV, and 3 aneurysms of the visceral aortic patch). RESULTS: In the hybrid group, 32 visceral bypasses were completed and endovascular TAAA repair was successful in all cases. No intraoperative deaths occurred. Perioperative mortality was 23%, and morbidity was 30.8% (renal failure in 2, respiratory failure in 1, and delayed transient paraplegia in 1). At a median follow-up of 14.9 months (range, 11 days to 59.4 months), all grafts were patent at postoperative computed tomography angiography and no aneurysm-related deaths, endoleak, stent graft migration, or morbidity related to visceral revascularization had occurred. No conventionally treated patients died intraoperatively. Perioperative mortality was 17.2% and morbidity was 44.8% (respiratory failure in 7, coagulopathy in 1, renal failure in 2, and paraplegia in 3). At a median follow-up of 5.4 years (range, 1.7 to 7.9 years), no significant complications related to aortic repair occurred, except for three patients (10.3%) with asymptomatic dilatation of the visceral aortic patch<5 cm undergoing radiologic surveillance. CONCLUSION: Hybrid TAAA repair is technically feasible in selected cases. Perioperative morbidity and mortality were considerable in our subset of high-risk patients with prior aortic surgery, but no aneurysm-related or procedure-related complications were reported at mid-term follow-up. Hybrid TAAA repair did not lead to a significant improvement in outcomes compared with open TAAA repair in a similar group of patients. Larger series are required for valid statistical comparisons and longer follow-ups are necessary to evaluate the durability of hybrid repairs.     

Hybridverfahren zur stentgestützten Ausschaltung eines thorakoabdominalen Aortenaneurysmas

Repair of a thoracoabdominal aortic aneurysm (TAAA) can nowadays be carried out with open surgery, if necessary using a heart-lung machine, using branched grafts or combined open and endovascular procedures as a so-called hybrid operation. This technique involves an initial step of so-called abdominal debranching, i.e. open revascularization of renal and visceral vessels. The second step involves stent-assisted repair of the aneurysm. This technique avoids high aortic cross-clamping which may be responsible for paraplegia and renal failure. In contrast to branched grafts it has the advantage that side branches which can possibly become detached from the main stent are unnecessary. The concept presented in this article represents an alternative treatment for TAAA, in particular for patients unfit for open repair involving two body cavities.     

Aortenzentren

The ideal aortic center is a maximum care center which treats all pathologies from the aortic root downwards, including the side branches and target organs. Furthermore, it offers the best quality of all treatment modalities round the clock. Should aortic surgery only be performed at ideal aortic centers? Meta-analyses, which investigated the volume-outcome relationship for abdominal aortic aneurysm (AAA) surgery identified a hospital and/or surgeon low annual operation volume as being a significant mortality predictor. Data from these studies suggested that AAA surgery should be performed only at high-volume centers but there is no evidence to centralize patients with infrarenal, juxtarenal and suprarenal AAA in maximum care aortic centers as defined above. However, absolutely safe AAA surgery requires a competent and experienced team, a minimal annual case volume and an adequate infrastructure. These conditions are more or less applicable to thoracic endovascular aortic repair (TEVAR). In contrast thoracic aortic aneurysm (TAA) open repair and all thoracic abdominal aortic aneurysms (TAAA) should be treated in specialized aortic centers because TAA(A) surgery requires high expertise and vast experience as well as extensive technical equipment to provide extracorporeal circulation and neuromonitoring.     

Repair of thoracoabdominal aortic aneurysms with fenestrated and branched endovascular stent grafts

OBJECTIVE: To report the repair of thoracoabdominal aortic aneurysms (TAAAs) with fenestrated and branched endovascular stent grafts (EVSGs). METHODS: Four patients with asymptomatic TAAAs were treated with custom-designed Zenith fenestrated and branched EVSGs. Three patients had undergone previous open aortic aneurysm repair. Thirteen visceral vessels in four patients were targeted for incorporation by graft fenestrations and branches. RESULTS: The fenestration/orifice interface was secured with balloon-expandable Genesis stents or Jostent stent grafts in 9 of 13 target vessels. Completion angiography demonstrated antegrade perfusion in 12 of 13 target vessels. One renal artery occluded because of graft rotation during deployment. There were no endoleaks. Three patients required additional surgical procedures related to access vessels. One patient required reoperation for bleeding from an extra-anatomic bypass graft and subsequently died from multisystem organ failure. Three patients made an uncomplicated recovery. No patient developed spinal cord ischemia. Computed tomography at 12 months in the 3 survivors demonstrated complete aneurysm exclusion with antegrade perfusion in all 10 target vessels. CONCLUSIONS: TAAA repair with fenestrated and branched EVSGs is feasible and provides an acceptable and promising alternative to conventional surgical repair in selected patients.     

Open repair for pararenal abdominal aortic aneurysm: the strategy and pitfalls for safe surgery

Pararenal abdominal aortic aneurysm (PRAAA) includes two types of AAA : juxtarenal (JRAAA) and suprarenal (SRAAA). JRAAA is defined as aneurysms that extend up to but do not involve the renal arteries, necessitating suprarenal aortic clamping for repair. SRAAA is defined as aneurysms that extend up to the superior mesenteric artery, involving one or both renal arteries to be repaired. The surgical repair of PRAAAs requires more extensive aortic exposure and may result in ischemic injury to kidneys and visceral organs with higher morbidity and mortality compared with infrarenal AAAs. The four approaches to PRAAA repair are: 1) midline abdominal incision, transperitoneal, left renal vein divided or mobilized; 2) midline abdominal incision, transperitoneal, left medial visceral rotation technique 3) left flank incision, retroperitoneal; and 4) thoracoabdominal incision, thoracoretroperitoneal approach. The four positions of proximal clamping are: 1) suprarenal; 2) interrenal; 3) supramesenteric; and 4) supraceliac aorta. The surgical strategy should be determined based on computed tomography and magnetic resonance angiography imaging, and severe atherosclerotic or calcified aorta should never be clamped to prevent lethal embolic complications. Although developing fenestrated endovascular technology can be used in some cases of PRAAA repair, open surgery with thorough preoperative assessment and careful utilization of techniques to prevent visceral and renal ischemic injury is safe, effective, and durable and remains the gold standard for repair.     

Thoracoabdominal aortic aneurysm repair in patients with marfan syndrome.

OBJECTIVE: We assessed the surgical outcome of descending thoracic aortic aneurysm repair (DTAA) and thoracoabdominal aortic aneurym (TAAA) repair in patients with Marfan syndrome. METHODS: During a six year period, 206 patients underwent DTAA and TAAA repair. In 22 patients, Marfan syndrome was confirmed. The median age was 40 years with a range between 18 and 57 years. The extend of the aneurysms included 6 DTAA (1 with total arch, 2 with distal hemi-arch), 11 type II TAAA (2 with total arch, 3 with distal hemi-arch), 4 type III and one type IV TAAA. All patients suffered from previous type A (n=6) or type B (n=16) aortic dissection and 15 already underwent aortic procedures like Bentall (n=7) and ascending aortic replacement (n=8). All patients were operated on according to the standard protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion and monitoring motor evoked potentials. In patients undergoing simultaneous arch replacement (via left thoracotomy), transcranial Doppler and EEG assessed cerebral physiology during antegrade brain perfusion. In four patients circulatory arrest under moderate hypothermia was required. RESULTS: In-hospital mortality did not occur. Major postoperative complications like paraplegia, renal failure, stroke and myocardial infarction were not encountered. Mean pre-operative creatinine level was 125mmol/L, which peaked to a mean maximal level of 130 and returned to 92mmol/L at discharge. Median intubation time was 1.5 days (range 0.33-30 days). Other complications included bleeding requiring surgical intervention (n=1), arrhythmia (n=2), pneumonia (n=2) and respiratory distress syndrome (n=1). At a median follow-up of 38 months all patients were alive. Using CT surveillance, new or false aneurysms were not detected, except in one patient who developed a visceral patch aneurysm six years after open type II repair. CONCLUSION: Surgical repair of descending and thoracoabdominal aortic aneurysms provides excellent short- and mid-term results in patients with Marfan syndrome. In this series, a surgical protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion and monitoring motor evoked potentials resulted in low morbidity and absent mortality. These outcomes of open surgery should be considered when discussing endovascular aneurysm repair in Marfan patients.     

Endovascular treatment of thoracoabdominal aortic aneurysms

Open surgical repair of thoracoabdominal aortic aneurysms (TAAA) bridges the aneurysm with a large, conventional, unstented graft and restores flow to the visceral arteries through short grafts or direct sutured connections between the visceral arterial orifices and the primary conduit. The combination of retrograde visceral bypass and endovascular aneurysm exclusion substitutes an endovascular stent-graft for a standard graft, stented overlaps for sutured anastomoses, and transluminal insertion for direct aortic exposure. Compared to open surgery, the combination treatment requires less dissection, and causes less hemodynamic instability, and lower complication rates, particularly paraplegia. The multi-branched stent-graft substitutes endovascular visceral bypass through branches of the stent-graft for surgical visceral bypass through branches of a conventional extraluminal graft, which has the potential to further reduce surgical dissection, hemodynamic instability, and complication rates. We favor a modular approach in which short, axially oriented cuffs are extended into the visceral arteries, using self-expanding covered stents. In the past year, we have used this approach to implant multi-branched thoracoabdominal stent-graft in 16 patients. In our opinion, this approach will eventually assume a prominent role in the management of TAAA.     

Hybrid procedures for the treatment of thoracoabdominal aortic aneurysms and dissections

The search for less invasive therapeutic approaches to thoracoabdominal aortic aneurysms (TAAAs) brought endovascular procedures to establish themselves as alternatives to open surgery in high-risk patients. Aim of this study is to illustrate the hybrid - open and endovascular - treatment of dissecting and non-dissecting TAAAs, and to analyze short and midterm results at our Center. We analyzed 41 high-risk patients who underwent hybrid TAAA repair (dissecting TAAA in 17% of cases) with a variety of visceral rerouting configuration and of commercially available thoracic endografts. Thirty-one simultaneous (76%) and 10 staged procedures (24%) were performed with a four-vessel revascularization in 13 cases (32%), a three-vessel in 9 (22%) and a two-vessel in 19 (46%). No intraoperative deaths were observed in our series, with a technical success in endovascular TAAA repair of 100%. Two patients died in the intersurgical time. A perioperative mortality of 13% and a perioperative morbidity of 32% were recorded, including one case (2.4%) of permanent paraplegia. At a median follow-up of 23.3 months, we observed a visceral graft occlusion rate of 6%, three type II endoleak and one endograft migration. Six patients died for unrelated events. Typical complications of conventional TAAA open surgery have been not eliminated by hybrid repair and still significant mortality and morbidity have been reported. Dissecting etiology did not negatively affect the outcome of hybrid repair in our experience. Fate of visceral bypasses and incidence of endoleak and other endograft-related complications need to be carefully assessed. Hybrid TAAA repair should nowadays be limited as alternative to simple observation in patients unfit for the conventional open repair.     

The association between co-morbidity and mortality after abdominal aortic aneurysm endografting in patients ineligible for elective open surgery.

OBJECTIVE: To investigate whether co-morbidity affects mortality after endovascular stenting in patients who are fit and unfit for open surgery. METHODS: Data were obtained from the EUROSTAR registry. The association between co-morbidity and mortality was examined by Cox proportional hazards models. RESULTS: Between 1994 and July 2000, 2862 patients underwent aneurysm stenting; 381 were unfit for open surgery. The early/late mortality rates for patients fit for surgery, patients unfit for surgery and patients unfit for anaesthesia were 2.7/5.2%, 5.1/11.4% (p=0.035/p<0.0001) and 3.7/11.0% (NS/p=0.016), respectively. The survival curves among patients with poor medical condition were significantly worse than in those patients with a good medical condition (p=0.001). The presence or absence of co-existing diseases did not affect the mortality rate in patients unfit for open surgery. The age-adjusted mortality risks of patients fit for open surgery and pulmonary disease or diabetes mellitus were 1.41 (1.02-1.95) and 1.75 (1.12-2.74), respectively. CONCLUSIONS: Patients with co-morbidity had a significantly higher mortality after aortic endografting compared with patients fit for open surgery. Co-morbidity did not increase mortality after endovascular abdominal repair in patients unfit for open surgery. Endovascular repair of abdominal aortic aneurysm seems to have a limited benefit in patients unfit for open surgery.     

Surgical Repair of Juxtarenal Abdominal Aortic Aneurysms and safety of Suprarenal Aortic Clamping

Background

Juxtarenal abdominal aortic aneurysm (AAA) comprises 15–20% of all AAAs and often requires open surgical repair (OSR) due to anatomical limitations associated with endovascular aneurysm repair (EVAR), particularly in the case of hostile proximal necks. This study aimed to evaluate short- and long-term outcomes of suprarenal clamping during OSR of juxtarenal AAAs and compare the outcomes of this technique with those of infrarenal clamping for AAAs.

Methods

Between January 1 2014, and December 31 2016, 289 consecutive patients aged ≥40 years underwent primary repair for infrarenal AAAs, including 141 OSRs and 148 EVARs. Of the 141 patients, 20 were excluded and totally, 121 patients were included.

Results

All patients had fusiform-type AAAs and were divided into infrarenal (N = 98) or suprarenal (N=23) clamp groups. The mean follow-up period was 51.4 months (95% CI: 48.6–54.2). Mean survival time was 51.4 months (95% CI: 48.6–54.2). Thirty-day mortality was 0.8%, and there was no significant difference between two groups (P > .999). Renal complication in infrarenal clamp group was 4.1% and suprarenal clamp group was 4.3% (P > .999). Old age (HR: 1.084; 95% CI: 1.025–1.147; P=.005) and high ASA score (HR: 2.361; 95% CI: 1.225–4.553; P = .010) were substantially associated with in-hospital complications.

Conclusions

Although endovascular procedures for repairing juxtarenal AAAs, such as fenestrated EVAR, have been developed, surgical repair is the standard treatment for juxtarenal AAAs. Morbidity and mortality due to open surgery were not higher in the juxtarenal AAA group than in the infrarenal AAA group. Therefore, need for suprarenal clamp should not preclude OSR and also there is continued need for training in surgical exposure of juxtarenal AAA and OSR.

     

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.     

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.     

Open surgical repair of thoracoabdominal aortic aneurysms

Despite much advancement in preoperative evaluation and perioperative care of patients with thoracoabdominal aortic aneurysms (TAAA), open surgical repair of TAAAs remains a formidable challenge for the vascular surgeon. It requires extensive dissection and mobilization of the aorta and its branches, as well as cross-clamping of the aorta above intercostal and visceral arteries. Over the past decade, the mortality and morbidity associated with open TAAA repair have improved significantly. However, it remains one of the most complex, extensive surgical procedures performed in the field of vascular surgery. Recently, there has been much attention directed at less invasive methods such as the so-called "hybrid" or "debranching" procedure, or complete endovascular repair with fenestrated and branched endografts for repairing TAAAs. However, the gold standard for repair of TAAA remains open surgery, and this article summarizes the clinical outcomes of open surgical repair of TAAAs during the past decade (2000-2010) to provide a benchmark for comparison with results from previous decades and also with which to compare the results of modern-day hybrid and/or complete endovascular techniques.     

Extended use of endovascular aneurysm sealing: Chimneys for juxtarenal aneurysms

Hostile infrarenal aortic neck anatomy presents a challenge for the endovascular treatment of abdominal aortic aneurysm. Open surgical repair has been seen as the gold standard treatment for juxtarenal abdominal aortic aneurysm; however, endovascular techniques are now becoming more prevalent, particularly in patients deemed high risk for morbidity and mortality with open repair. The morphology of an aneurysm is a determinant of long-term outcomes, and short aneurysm necks are associated with poorer outcomes and a higher rate of secondary reinterventions. Parallel grafts have been used in combination with endovascular aneurysm repair to elongate the sealing zone into the paravisceral segment of the aorta. This technique is associated with a risk of proximal Type I endoleak due to “guttering.” This risk may be decreased when parallel grafts are used in combination with endovascular aneurysm sealing and, as such, this technique may represent an alternative to current techniques for the treatment of juxtarenal abdominal aortic aneurysm, such as the use of conventional bifurcated grafts (with or without parallel grafts) and fenestrated endovascular stent grafts.     

Do branched and fenestrated devices have a role in chronic type B aortic dissection?

Morbidity and mortality after conventional open repair of post-dissecting thoracoabdominal aortic aneurysms (TAAA) remain high despite the improvement of results. Recently, "hybrid" open de-branching procedures combined with endovascular stent-grafting of the atherosclerotic thoracic aortic aneurisms have been performed, as an alternative approach. However, patients with significant cardiac, pulmonary or renal comorbidities, may represent an unfit cohort also for such hybrid procedures, and, of consequence, may be resigned to medical treatment. Recent experiences with fenestrated and branched stent-grafts have opened new opportunities in the treatment of extensive aortic aneurysms involving the visceral and renal arteries, particularly in case of atherosclerotic aneurysms. Post-dissection thoracoabdominal aneurysms present with additional challenges such as narrow true lumen at the level of the visceral vessels origin, and the lack of a stable distal landing zone. In this report, we discuss the role of fenestrated and branched stent-grafts as feasible treatment of post-dissecting TAAA.     

Acute and chronic open conversion after endovascular aortic aneurysm repair: a 14-year review

OBJECTIVE: This study reviewed outcomes of patients requiring surgical conversion after endovascular abdominal aortic aneurysm (AAA) repair. METHODS: Records for all patients undergoing open conversion after endovascular AAA repair were reviewed. RESULTS: From 1993 to 2006, 574 patients underwent endovascular repair for AAA. Seventeen patients, including three patients who underwent prior endovascular repair at other centers, required surgical conversion with complete (n = 9) or partial graft removal (n = 8). Five patients required immediate conversion (acute), and 12 underwent delayed conversion 4 to 72 months after endovascular repair. Indications for acute conversion were large type I endoleak (n = 3, 60%), including one patient with graft migration, and retroperitoneal bleeding (n = 2, 40%). Indications for chronic conversion were endoleak with increasing aneurysm size (n = 9, 75%), stent fracture without endoleak (n = 1, 8%), delayed retroperitoneal bleeding (n = 1, 8%), and infection (n = 1, 8%). Suprarenal aortic cross-clamping was required in two patients (12%), and endograft components were retained in eight (47%). An aortic occlusion balloon placed through the body of the existing endograft facilitated proximal control in three patients. There were two perioperative deaths in the acute conversion group (2/5; 40%) and none in the delayed conversion group (P = .04). Five-year actuarial survival was 71.9%. Mean follow-up was 41.6 +/- 32.2 months. Retained endovascular components in patients with partial graft removal remained stable during follow-up. CONCLUSIONS: Surgical conversion after endovascular AAA repair can be performed without suprarenal clamping in most patients. Endovascular aortic control with a balloon avoids suprarenal exposure. Partial endograft removal in selected patients facilitates open conversion and appears durable. Acute conversion is associated with increased mortality.     

Endovascular treatment of thoracoabdominal aortic aneurysms

OBJECTIVE: This study assessed the role of multibranched stent grafts for thoracoabdominal aortic aneurysm (TAAA) repair. METHODS: Self-expanding covered stents were used to connect the caudally directed cuffs of an aortic stent graft with the visceral branches of a TAAA in 22 patients (16 men, 6 women) with a mean age of 76 +/- 7 years. All patients were unfit for open repair, and nine had undergone prior aortic surgery. Customized aortic stent grafts were inserted through surgically exposed femoral (n = 16) or iliac (n = 6) arteries. Covered stents were inserted through surgically exposed brachial arteries. Spinal catheters were used for cerebrospinal fluid pressure drainage in 22 patients and for and spinal anesthesia in 11. RESULTS: All 22 stent grafts and all 81 branches were deployed successfully. Aortic coverage as a percentage of subclavian-to-bifurcation distance was 69% +/- 20%. Mean contrast volume was 203 mL, mean blood loss was 714 mL, and mean hospital stay was 10.9 days. Two patients (9.1%) died perioperatively: one from guidewire injury to a renal arterial branch and the other from a medication error. Serious or potentially serious complications occurred in 9 of 22 patients (41%). There was no paraplegia, renal failure, stroke, or myocardial infarction among the 20 surviving patients. Two patients (9.1%) underwent successful reintervention: one for localized intimal disruption and the other for aortic dissection, type I endoleak, and stenosis of the superior mesenteric artery. One patient has a type II endoleak. Follow-up is >1 month in 19 patients, >6 months in 12, and >12 months in 8. One branch (renal artery) occluded for a 98.75% branch patency rate at 1 month. The other 80 branches remain patent. There are no signs of stent graft migration, component separation, or fracture. CONCLUSIONS: Multibranched stent graft implantation eliminates aneurysm flow, preserves visceral perfusion, and avoids many of the physiologic stresses associated with other forms of repair. The results support an expanded role for this technique in the treatment of TAAA.