Open repair of juxtarenal aortic aneurysms (JAA) remains a safe option in the era of fenestrated endografts

Secondary Fill Minimizes Gutter Size in Chimney EVAS Configurations In Vitro

Purpose: To investigate in an in vitro model if secondary endobag filling can reduce gutter size during chimney endovascular aneurysm sealing (chEVAS). Materials and Methods: Nellix EVAS systems were deployed in 2 silicone juxtarenal aneurysm models with suprarenal aortic diameters of 19 and 24 mm. Four configurations were tested: EVAS with 6-mm balloon-expandable (BE) or self-expanding (SE) chimney grafts (CGs) in the renal branches of both models. Balloons were inflated simultaneously in the CGs and main endografts during primary and secondary endobag filling and polymer curing. Computed tomography (CT) was performed immediately after the primary and secondary fills. Cross-sectional lumen areas were measured on the CT images to calculate gutter volumes and percent change. CG compression was calculated as the reduction in lumen surface area measured perpendicular to the central lumen line. The largest gutter volume and highest compression were presented per CG configuration per model. Results: Secondary endobag filling reduced the largest gutter volumes from 99.4 to 73.1 mm³ (13.2% change) and 84.2 to 72.0 mm³ (27.6% change) in the BECG configurations and from 67.2 to 44.0 mm³ (34.5% change) and 92.7 to 82.3 mm³ (11.2% change) in the SECG configurations in the 19- and 24-mm models, respectively. Secondary endobag filling increased CG compression in 6 of 8 configurations. BECG compression changed by −0.2% and 5.4% and by −1.0% and 0.4% in the 19- and 24-mm models, respectively. SECG compression changed by 10.2% and 16.0% and by 7.2% and 7.3% in the 19- and 24-mm models, respectively. Conclusion: Secondary endobag filling reduced paragraft gutters; however, this technique did not obliterate them. Increased CG compression and prolonged renal ischemia time should be considered if secondary endobag filling is used.

Epidemiology, outcomes, and management of acute kidney injury in the vascular surgery patient

OBJECTIVE

Conventional clinical wisdom has often been nihilistic regarding the prevention and management of acute kidney injury (AKI), despite its being a frequent and morbid complication associated with both increased mortality and cost. Recent developments have shown that AKI is not inevitable and that changes in management of patients can reduce both the incidence and morbidity of perioperative AKI. The purpose of this narrative review was to review the epidemiology and outcomes of AKI in patients undergoing vascular surgery using current consensus definitions, to discuss some of the novel emerging risk stratification and prevention techniques relevant to the vascular surgery patient, and to describe a standardized perioperative pathway for the prevention of AKI after vascular surgery.

METHODS

We performed a critical review of the literature on AKI in the vascular surgery patient using the PubMed and MEDLINE databases and Google Scholar through September 2017 using web-based search engines. We also searched the guidelines and publications available online from the organizations Kidney Disease: Improving Global Outcomes and the Acute Dialysis Quality Initiative. The search terms used included acute kidney injury, AKI, epidemiology, outcomes, prevention, therapy, and treatment.

RESULTS

The reported epidemiology and outcomes associated with AKI have been evolving since the publication of consensus criteria that allow accurate identification of mild and moderate AKI. The incidence of AKI after major vascular surgery using current criteria is as high as 49%, although there are significant differences, depending on the type of procedure performed. Many tools have become available to assess and to stratify the risk for AKI and to use that information to prevent AKI in the surgical patient. We describe a standardized clinical assessment and management pathway for vascular surgery patients, incorporating current risk assessment and preventive strategies to prevent AKI and to decrease its complications. Patients without any risk factors can be managed in a perioperative fast-track pathway. Those patients with positive risk factors are tested for kidney stress using the urinary biomarker TIMP-2•IGFBP7, and care is then stratified according to the result. Management follows current Kidney Disease: Improving Global Outcomes guidelines.

CONCLUSIONS

AKI is a common postoperative complication among vascular surgery patients and has a significant impact on morbidity, mortality, and cost. Preoperative risk assessment and optimal perioperative management guided by that risk assessment can minimize the consequences associated with postoperative AKI. Adherence to a standardized perioperative pathway designed to reduce risk of AKI after major vascular surgery offers a promising clinical approach to mitigate the incidence and severity of this challenging clinical problem.

Anatomical Considerations and Open Surgery to Treat Juxtarenal Abdominal Aortic Aneurysms

Introduction:

Historically, the open approach to the abdominal aorta has been transperitoneal (TP). In comparison, a retroperitoneal (RP) incision exposes the lateral wall of the suprarenal aorta for clamp application and midline structures such as the duodenum and pancreas are not encountered. Proximal clamp position for open repair of juxtarenal abdominal aortic aneurysm (JR-AAA) is suprarenal, supra-superior mesenteric, or supraceliac. While RP and TP approaches have previously been compared for physiological reasons, there are currently no randomized controlled trials comparing these methods from an anatomical perspective.

Aims:

The primary aim is to examine the evidence for adopting an RP approach for JR-AAA and compare it with TP approach from an anatomical perspective. The secondary aim is to assess optimum proximal clamp position and its effect on renal function and mortality for the 2 approaches.

Methods/Design:

Literature was reviewed searching databases Medline and Embase for studies on clamp positioning in JR-AAA repair using a TP or RP approach, up to December 2017.

Conclusions:

There is no clear evidence for the optimum cross-clamp position for open repair of JR-AAAs. More proximal clamps provide adequate operative space with the possible downside of increased afterload leading to visceral and renal ischemia. Clamps placed inferior to the superior mesenteric artery allow continued bowel and hepatic perfusion with the potential to cause trauma to the adjacent aortic branches during application. As far as the optimum approach is concerned, many series show a strong trend for RP as a more proximal clamp is required. Significant numbers develop renal failure after JR-AAA repair, with most recovering fully irrespective of the clamp position.

Patient and Aneurysm Characteristics Predicting Prolonged Length of Stay After Elective Open AAA Repair in the Endovascular Era

INTRODUCTION

Open aortic aneurysm repair (AAA) repair can be resource intensive and associated with a prolonged length of stay (LOS). We sought to examine patient and aneurysm predictors of prolonged LOS to better identify those at risk in the preoperative setting.

METHODS

Patient data were obtained from the targeted AAA American College of Surgery National Surgical Quality Improvement Program database from 2012 to 2014 of patients undergoing open AAA repair. Multivariable logistic regression was used to determine predictors of prolonged postoperative LOS defined as greater than 10 days (75th percentile).

RESULTS

There were 1172 open AAA repairs identified. The majority (54%) of patients were older than 70 years and male (74%). Surgical approach was transperitoneal (70.9%) and retroperitoneal (29.1%). Aneurysms were 51.4% infrarenal, 33% juxtarenal, 5.7% pararenal, 7.4% suprarenal, and 2.5% type IV thoracoabdominal. Mean and median LOS were 9.1 ± 7.4 and 7 (0-72) days, respectively. Independently associated with extended LOS factors were visceral revascularization (odds ratio [OR]: 5.32, 95% confidence interval [CI]: 2.77-10.22, P < .001), type IV thoracoabdominal extent (OR: 3.09, 95% CI: 1.01-9.46, P = .048), suprarenal extent (OR: 1.89, 95% CI: 1.07-3.34, P = .029) and juxtarenal (OR: 1.43, 95% CI: 1.01-2.02, P = .004), non-Caucasian race (OR: 2.80, 95% CI: 1.77-4.41, P < .001), chronic obstructive pulmonary disease (OR: 1.76, 95% CI: 1.20-2.59, P = .004), not-from-home admission (OR: 1.91, 95% CI: 1.13-3.24), and age greater than 70 (OR: 1.49, 95% CI: 1.08-2.05, P = .014).

CONCLUSION

We identified patient and aneurysm characteristics independently associated with protracted LOS following open AAA repair. Prospective identification of high-risk patients may allow physicians and hospitals to engage in multidisciplinary collaborations preoperatively to try to improve LOS in this resource-intensive population.

Long-term fate of renal function after open surgery for juxtarenal and pararenal aortic aneurysm

BACKGROUND

Although the indications for endovascular aneurysm repair for abdominal aortic aneurysm have been expanding, our primary strategy for pararenal and juxtarenal abdominal aortic aneurysm (P/JRAA) is open surgery (OS). One consequence of OS for P/JRAA is transient renal ischemia owing to renal artery clamping, which can be followed by acute kidney injury (AKI). Prior studies referred to the impact of renal ischemia on AKI, but they have rarely evaluated longer-term renal function. This study focused on a chronic renal decline (CRD) during follow-up.

METHODS

A retrospective review of our series of P/JRAA treated with OS from 2007 to 2015. Patients on hemodialysis at the time of surgery were excluded. Preoperative renal function was estimated using the chronic kidney disease (CKD) staging system. Postoperative AKI was defined by the RIFLE criteria (Risk, Injury, Failure, Loss of function, End-stage renal disease). CRD was defined as progression in CKD stage or estimated glomerular filtration rate (eGFR) decline of >20%.

RESULTS

Among 451 elective OS, 111 underwent repair for P/JRAA. Three patients were excluded because of preoperative hemodialysis. Consequently, 108 patients were enrolled. Preoperatively, 41 patients (38.0%) had CKD stage 3 (eGFR < 60 mL/min/1.73 m²). Eight patients (7.2%) were in stage 4 (eGFR < 30 mL/min/1.73 m²). Proximal clamping was supraceliac (6 patients), suprarenal (34 patients), and inter-renal (68 patients). The median renal ischemic time was 33 minutes. The left renal vein was divided in 24 patients. Fourteen renal arteries in 14 patients were revascularized. Cold renal perfusion was applied in 11 patients. One in-hospital death was excluded from these analyses. AKI was observed in 20 patients (18.7%). One patient required temporary hemodialysis. During a median renal function follow-up for 24.5 months (interquartile range, 3.34-48.4), 17 patients (15.9%) had CRD. One patient required hemodialysis 5 years after surgery. In univariate analysis, CKD stages 3 and 4 were significant predictors for CRD (P = .014 and P < .001, respectively). Cold renal perfusion was associated with a higher risk of CRD (P = .047). On multivariate analysis, preoperative CKD stage 3 (hazard ratio, 4.22; 95% confidence interval, 1.10-16.3; P = .036) and stage 4 (hazard ratio, 59.72; 95% confidence interval, 10.13-352.0; P < .001) were identified as risk factors. In patients with CKD stage ≤2, the estimated freedom from CRD at 5 years was 96.6 ± 3.4%.

CONCLUSIONS

CKD stage ≥3 was a significant risk for CRD after OS for P/JRAA. Renal artery clamping seemed innocuous for patients with a preoperative eGFR of ≥60 mL/min/1.73 m² in terms of CRD. No significant impact of left renal vein division on CRD was confirmed.

Evaluation of the renal function using serum Cystatin C following open and endovascular aortic aneurysm repair

Objectives

Controversies regarding renal function impairment after open and endovascular aortic aneurysm repair still exist. The purpose of this study was to evaluate the renal function following open repair and endovascular aneurysm repair using Cystatin C.

Methods

This prospective, observational case–control study was conducted in tertiary referral centre over 3 years, starting from 2012. In total, 60 patients operated due to infrarenal AAA either by means of open repair (30 patients) or endovascular aneurysm repair (30 patients) were included in the study. Biochemical markers of renal function (sCr, urea, potassium) were recorded pre-operatively and at these specific time points, immediately after the operation and at discharge, home (third postoperative day, endovascular aneurysm repair group) or from intensive care unit (third postoperative day, open repair group). Multivariate and propensity score adjustments were used to control for the baseline differences between the groups.

Results

Creatinine levels in serum remained unchanged during the hospital stay in both groups without significant differences at any time point. Cystatin C levels in endovascular aneurysm repair patients significantly increased postoperatively and restored to values comparable to baseline at the discharge (0.865 ± 0.319 vs. *0.962 ± 0.353 vs. 0.921 ± 0.322, * p < 0.001). Cystatin C levels in patients treated with the open surgery was decreasing over time but not statistically significant comparing to Cystatin C values at the admission. However, decrease in Cystatin C serum levels in patients treated with conventional surgery resulted in statistically significant lower values compared to endovascular aneurysm repair patients both postoperatively and at the time of discharge (0.760 ± 0.225 vs. 0.962 ± 0.353, p < 0.05; 0.750 vs. 0.156, p < 0.05). Both multivariate linear regression models and propensity score adjustment confirm that, even after correction for previously observed intergroup differences, type of surgery, i.e. endovascular aneurysm repair is independently associated with the higher levels of Cystatin C both postoperatively and at the discharge.

Conclusions

Dynamics of Cystatin C levels have been proven as a more vulnerable marker of renal dysfunction. Endovascular aneurysm repair is associated with higher levels of kidney injury markers.

Early Experience with Snorkels and Chimneys for Expanding the Indications for Use of Endovascular Aneurysm Repair

BACKGROUND

Although fenestrated and branched devices for juxtarenal and paravisceral aneurysms are available worldwide, limited ultrasound availability has perpetuated widespread utilization of adjunctive techniques for the endovascular treatment of these aneurysms. The objective of the study is to report on the technical feasibility and short-term durability of parallel grafts for juxtarenal and paravisceral aneurysms.

METHODS

We performed a retrospective review of a prospectively collected endovascular aneurysm repair database, including all patients who underwent a parallel stent procedure. End points included were the following: (1) number of vessels snorkeled; (2) endoleaks; (3) morbidity and mortality; and (4) snorkel graft patency.

RESULTS

Forty patients (85% male, mean 77.8 years) were treated for primary aneurysms (26), para-anastomotic aneurysms (6) following prior open repair, and endoleaks (8) following prior endovascular repair. Sixty-nine visceral vessels were preserved. Bilateral femoral arteries were accessed, as well as the left upper extremity via percutaneous (n = 5) brachial, open brachial (n = 15), or open axillary (n = 20) artery exposure with conduit. The mean length of surgery was 253 min with median intensive care unit stay of 2 days. There were 6 endoleaks noted, 8 access site complications, 1 perioperative death, and 3 branch vessel stent occlusions. We have a mean follow-up time of 17.6 months (range 3-44).

CONCLUSIONS

Parallel stent-graft repair for paravisceral aneurysms is feasible and has acceptable technical/clinical success and complication rates. Although long-term follow-up is still needed, this technique fills the gap in endovascular options for poor open surgical candidates in whom fenestrated devices are not available.

Comparison of perioperative outcomes in endovascular versus open repair for juxtarenal and pararenal aortic aneurysms: A propensity-matched analysis

Objective

Endoluminal aortic aneurysm repair is suitable within certain anatomic specifications. This study aims to compare 30-day outcomes of endovascular versus open repairs for juxtarenal and pararenal aortic aneurysms (JAA/PAAs).

Methods

The ACS-NSQIP database was queried from 2012 to 2015 for JAA/PAA repairs. Procedures characterized as emergent were included in the study; however, failed prior repairs and ruptured aneurysms were excluded. The preoperative and perioperative patient characteristics, operative techniques, and outcome variables were compared between the open aortic repair and the endovascular aortic repair groups. Propensity scoring was performed to clinically match open aortic repair and endovascular aortic repair groups on preoperative risk and select perioperative factors that differed significantly in the unmatched groups. Outcome comparisons were then performed between matched groups.

Results

A total of 1005 (789 JAAs and 216 PAAs) aneurysm repairs were included in the study. Of these, there were 395 endovascular aortic repairs and 610 open aortic repairs. Propensity scoring created a matched group of 263 endovascular aortic repair and 263 open aortic repair patients. There was no statistically significant difference in 30-day mortality rates between matched endovascular aortic repair and open aortic repair patients (2.7% vs. 5.7%). The endovascular aortic repair group had a shorter ICU length of stay and overall hospital stay. The 30-day morbidity significantly favored endovascular aortic repair over open aortic repair (16% vs. 35%, p < 0.001). The main drivers of morbidity for endovascular aortic repair versus open aortic repair included return to the OR (6.8% vs. 15%, p < 0.001), rate of cardiac or respiratory failure (7.6% vs. 21%, p = 0.001), rate of renal insufficiency or failure (3.8% vs. 9.9%, p = 0.009), and rate of pneumonia (1.5% vs. 6.8%, p = 0.004).

Conclusions

There is no difference in mortality rates between endovascular aortic repair versus open aortic repair when repairing JAAs/PAAs. There is a significant difference in overall morbidity, and ICU and hospital length of stay favoring endovascular aortic repair over open aortic repair. This supports the expanded applicability and efficacy of endovascular repair for complex aneurysms.

Fenestrated and Branched Stent Grafting in Complex Aneurysmatic Aortic Disease: A Single-Center Early Experience

BACKGROUND

The aim of this study is to present our early experience and highlight the technical difficulties associated with the use of fenestrated and branched stent grafts to treat patients with juxtarenal abdominal aortic aneurysm (AAA), pararenal AAA, and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

A prospectively held database maintained at our department was queried for patients who have undergone branched and fenestrated stent grafting for AAA or TAAA treatment. Indication for repair, comorbidity precluding open repair, technical challenges associated with the repair, as well as operative mortality, morbidity, and reintervention rate were evaluated.

RESULTS

A total of 8 patients underwent repair with a fenestrated or branched stent graft. All patients had aneurysmal degeneration of the juxtarenal aorta, pararenal aorta, and thoracoabdominal aorta not suitable to standard endovascular techniques. Two patients had a prior aortic repair, a failed migrated stent graft, and an old surgical tube graft after an open repair. One patient had a type III TAAA and 1 patient had a postdissection TAAA type I. For all patients, target vessel success rate was 96.4% (27/28) and mean hospital stay was 6.0 days (range 3-21). Thirty-day and 1-year mortality were 0%. Mean follow-up was 23 months (range 7-45). Two endoleaks occurred, 1 type III and 1 type II, which were treated endovascularly. No death or major complication occurred during follow-up.

CONCLUSIONS

Fenestrated and branched endovascular stent grafts can be used to repair juxtarenal AAA, pararenal AAA, and TAAA in patients with significant comorbidities. However, several technical challenges have to be overcome due to the unique complex aortic pathology of each patient.

Organ protection during aortic cross-clamping

Open surgical repair of an aortic aneurysm requires aortic cross-clamping, resulting in temporary ischemia of all organs and tissues supplied by the aorta distal to the clamp. Major complications of open aneurysm repair due to aortic cross-clamping include renal ischemia-reperfusion injury and postoperative colonic ischemia in case of supra- and infrarenal aortic aneurysm repair. Ischemia-reperfusion injury results in excessive production of reactive oxygen species and in oxidative stress, which can lead to multiple organ failure. Several perioperative protective strategies have been suggested to preserve renal function during aortic cross-clamping, such as pharmacotherapy and therapeutic hypothermia of the kidneys. In this chapter, we will briefly discuss the pathophysiology of ischemia-reperfusion injury and the preventative measures that can be taken to avoid abdominal organ injury. Finally, techniques to minimize the risk of complications during and after open aneurysm repair will be presented.

Patient selection and perioperative outcomes are similar between targeted and nontargeted hospitals (in the National Surgical Quality Improvement Program) for abdominal aortic aneurysm repair

OBJECTIVE

The targeted vascular module in the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) consists of self-selected hospitals that choose to collect extra clinical details for better risk adjustment and improved procedure-specific outcomes. The purpose of this study was to compare patient selection and outcomes between targeted and nontargeted hospitals in the NSQIP regarding the operative management of abdominal aortic aneurysm (AAA).

METHODS

We identified all patients who underwent endovascular aneurysm repair (EVAR) or open AAA repair from 2011 to 2013 and compared cases by whether the operation took place in a targeted or nontargeted hospital. EVAR and open repair as well as intact and ruptured aneurysms were evaluated separately. Only variables contained in both modules were used to evaluate rupture status and operation type. All thoracoabdominal aneurysms were excluded. Univariate analysis was performed for intact and ruptured EVAR and open repair grouped by complexity, defined as visceral involvement in open repair and a compilation of concomitant procedures for EVAR. Multivariable models were developed to identify effect of hospital type on mortality.

RESULTS

There were 17,651 AAA repairs identified. After exclusion of aneurysms involving the thoracic aorta (n = 352), there were 1600 open AAA repairs at targeted hospitals (21% ruptured) and 2725 at nontargeted hospitals (19% ruptured) and 4986 EVARs performed at targeted hospitals (6.7% ruptured) and 7988 at nontargeted hospitals (5.2% ruptured). There was no significant difference in 30-day mortality rates between targeted and nontargeted hospitals for intact aneurysms (EVAR noncomplex, 1.8% vs 1.4% [P = .07]; open repair noncomplex, 4.2% vs 4.5% [P = .7]; EVAR complex, 5.0% vs 3.2% [P = .3]; open repair complex, 8.0% vs 6.0% [P = .2]). For ruptured aneurysms, again there was no difference in mortality between the targeted and nontargeted hospitals (EVAR noncomplex, 23% vs 25% [P = .4]; open repair noncomplex, 38% vs 34% [P = .2]; EVAR complex, 29% vs 33% [P = 1.0]; open repair complex, 27% vs 41% [P = .09]). Multivariable analysis further demonstrated that having an operation at a targeted vs nontargeted hospital had no impact on mortality for both intact and ruptured aneurysms (odds ratio, 1.1 [0.9-1.4] and 1.0 [0.8-1.3], respectively).

CONCLUSIONS

This analysis highlights the similarities between targeted and nontargeted hospitals within the NSQIP for AAA operative management and suggests that data from the targeted NSQIP, in terms of AAA management, are generalizable to all NSQIP hospitals.

Fenestrated and Chimney Technique for Juxtarenal Aortic Aneurysm: A Systematic Review and Pooled Data Analysis

Juxtarenal aortic aneurysms (JAA) account for approximately 15% of abdominal aortic aneurysms. Fenestrated endovascular aneurysm repair (FEVAR) and chimney endovascular aneurysm repair (CH-EVAR) are both effective methods to treat JAAs, but the comparative effectiveness of these treatment modalities is unclear. We searched the PubMed, Medline, Embase, and Cochrane databases to identify English language articles published between January 2005 and September 2013 on management of JAA with fenestrated and chimney techniques to conduct a systematic review to compare outcomes of patients with juxtarenal aortic aneurysm (JAA) treated with the two techniques. We compared nine F-EVAR cohort studies including 542 JAA patients and 8 CH-EVAR cohorts with 158 JAA patients regarding techniques success rates, 30-day mortality, late mortality, endoleak events and secondary intervention rates. The results of this systematic review indicate that both fenestrated and chimney techniques are attractive options for JAAs treatment with encouraging early and mid-term outcomes.

Results of Open Surgical Repair of Chronic Juxtarenal Aortic Occlusion

PURPOSE

The aim of study was to review the results of open surgical repair (OSR) of chronic juxtarenal aortic occlusion (JRAO).

MATERIALS AND METHODS

We retrospectively reviewed the results of OSR performed in 47 patients (male, 92%; mean age, 59.9±9.3 years [range, 44-79]) with chronic JRAO during the past 21 years. In order to reduce intraoperative renal ischemic time (RIT), we excised a portion of the occluded segment of the infrarenal aorta without proximal aortic clamping. We then performed suprarenal aortic clamping with both renal arteries clamped, removed the proximal aortic thrombus cap, confirmed both renal artery orifices, and moved the suprarenal aortic clamp to the infrarenal aorta to allow renal perfusion and standard aortoiliac reconstruction. We investigated early (<30 days) postoperative surgical morbidity (particularly renal function), operative mortality, and longterm patient survival. We conducted risk factor analysis for postoperative renal insufficiency.

RESULTS

The mean intraoperative RIT was 10.7±5.5 minutes (range, 3-25), including 6 patients who underwent concomitant pararenal aortic thromboendarterectomy. Postoperatively, five (11%) patients had transient renal insufficiency, one had pneumonia, and one patient had an acute myocardial infarction. However, there was no operative mortality or newly developed dialysis-dependent renal failure. Postoperative follow up was available in 36 (77%) patients for a mean period of 6.3 years (range, 1 month-17 years). Kaplan Meier calculations of patient survival at 5 and 10 years after surgery were 91.2% and 83.6%, respectively.

CONCLUSION

We have experienced short RIT, acceptable early postoperative results and long-term survival after OSR of chronic JRAO.

Developing a new endograft for the treatment of juxtarenal aortic aneurysms: definition and experimentation

OBJECTIVES

To analyze angiotomographic parameters of juxtarenal aneurysms to assess the applicability of an endograft model to patients and to create in vitro and in vivo models to assess the new endograft.

METHODS

A total of 49 patients with juxtarenal aneurysms were submitted to angiotomographic evaluation, and parameters such as the aortic diameter, the length of the neck, and the angulations of the celiac trunk, superior mesenteric artery and renal arteries; the distances between them; and anatomic variations were analyzed. Based on these parameters, an endograft model was developed and tested in a newly created in vitro model of juxtarenal aneurysm. An experimental model of juxtarenal aneurysm was then established in six pigs weighing 50-60 kg to assess the new endograft model.

RESULTS

The angiotomographic parameters of juxtarenal aneurysm measured in this study were similar to those reported in the literature and allowed the development of an endograft based on the hourglass concept, which was applicable to 85.8% of the patients. The in vitro model of juxtarenal aneurysm evidenced good radiopacity and functionality and permitted adjustments in the new device and technical improvements in the procedures for treating these aneurysms. In addition, the porcine model of juxtarenal aneurysm was successfully created in all six animals using a bovine pericardial patch, and use of the new endograft in three pilot procedures evidenced its feasibility.

CONCLUSIONS

The Hourglass endograft was rendered applicable to treatment of the majority of patients with juxtarenal aneurysms simply by changing its diameter. Moreover, the new in vitro and in vivo models were shown to be effective for assessing both the presented endograft and experiments assessing the endovascular treatment of juxtarenal aneurysms.

Long-term survival and quality of life after open abdominal aortic aneurysm repair

BACKGROUND

Open repair of abdominal aortic aneurysm (AAA) generally involves postsurgery admission to the intensive care unit (ICU). Few studies have evaluated the impact of surgery for either ruptured or nonruptured AAA (with postoperative ICU treatment) on long-term survival and quality of life. The primary aim of this study was to quantify long-term survival and health-related quality of life (HrQpL) of a cohort of patients undergoing open AAA repair after hospital discharge.

METHODS

Consecutive patients undergoing open elective or acute AAA reconstruction with postoperative admission to the ICU and discharged alive from the hospital during 2009 were identified. Primary outcome measures were 1-year and long-term mortality. The secondary outcome was the HrQoL using the EuroQol-6D (EQ-6D) questionnaire at the end of the follow-up period.

RESULTS

A total of 263 patients were treated and postoperatively discharged alive: 56 had a ruptured AAA (rAAA), 35 a symptomatic AAA, and 172 an asymptomatic AAA. The 1-year mortality after open AAA repair was 8 %. Overall, 39 % of patients died within 10 postoperative years (mean 6.0 ± 2.8 years). Long-term survival of patients with a ruptured or symptomatic aneurysm was similar to that of patients undergoing elective aneurysm repair. Long-term HrQoL of the total study population was worse than that of an age-matched general Dutch population on the EQ-us (range 0-1, difference 0.12). This decrease in HrQoL was mainly seen in mobility, self-care, usual activities, and cognition.

CONCLUSIONS

Ten years after open AAA repair, the overall survival rate was 59 %. Long-term survival and HrQoL were similar for patients with a repaired ruptured or symptomatic aneurysm and those who underwent elective aneurysm repair. There were also no differences in patients with infrarenal versus juxtarenal/suprarenal aneurysms. Surviving patients had a lower HrQoL than the age-matched general Dutch population, especially regarding mobility, self-care, usual activities, and cognition.

N, Lichtenfels E, Aerts N. Surgical treatment of chronic aortoiliac occlusion

BACKGROUND: Chronic aortoiliac occlusion (CAIO) is a significant cause of lower limb ischemia and is often found in young patients who smoke. OBJECTIVE: To review recent results achieved treating CAIO patients with open surgery. METHODS: From November 2011 to April 2014, 21 patients with CAIO were treated at the Santa Casa de Misericórdia, Porto Alegre, Brazil. Demographic data, comorbidities, clinical presentation and surgical results were analyzed. RESULTS: Eleven women and ten men were treated with direct aortic bypass (DAB; n=18) or with extra-anatomic bypass (EAD; n=3). Mean age was 53.7 ± 7.3 years (range: 43-79 years) and all patients smoked. Thirteen patients (62%) had critical ischemia. Six of the patients treated with DAB (33.4%) also required additional revascularization (3 renal and 3 femoropopliteal procedures). Perioperative mortality was zero. Four patients (22.2%) suffered transitory renal dysfunction, but only one patient (5.6%) required hemodialysis. Median follow-up time was 17 months (range: 2-29 months) and there was just one late death, from ischemic heart disease, 7 months after the surgery on the abdominal aorta. CONCLUSIONS: Aortic reconstruction is a safe method for treating patients with CAIO, with low perioperative morbidity and mortality rates.

Fenestrated endovascular repair of abdominal aortic aneurysms is associated with increased morbidity but comparable mortality with infrarenal endovascular aneurysm repair

OBJECTIVE

A recent prospective study found that fenestrated endovascular abdominal aortic aneurysm (AAA) repair (FEVAR) was safe and effective in appropriately selected patients at experienced centers. As this new technology is disseminated to the community, it will be important to understand how this technology compares with standard endovascular AAA repair (EVAR). The goal of this study was to compare the outcomes of FEVAR vs EVAR of AAAs.

METHODS

The American College of Surgeons-National Surgical Quality Improvement Program database from 2005 to 2012 was queried for AAAs (International Classification of Diseases, Ninth Revision code 441.4). Patients were stratified according to procedure (FEVAR vs EVAR). A bivariate analysis was done to assess preoperative and intraoperative risk factors for postoperative outcomes. Thirty-day postoperative mortality and complication rates were described for each procedure type. Multivariable logistic regression was performed to assess the association between the type of procedure and the risk of postoperative complications.

RESULTS

A total of 458 patients underwent FEVAR and 19,060 patients underwent EVAR for AAA. Patients undergoing FEVAR were older (P = .02) and less likely to have a bleeding disorder (P = .046). Otherwise, the incidence of comorbidities in both groups was similar. FEVAR was associated with increased median operative time (156 vs 137 minutes; P < .001), and average postoperative length of stay (3.3 vs 2.8 days; P = .03). There was a statistically significant increase in overall complications (23.6% vs 14.3%; P < .001) and postoperative transfusions (15.3% vs 6.1%, P < .001) and trends toward increased cardiac complications (2.2% vs 1.3%; P = .09) and the need for dialysis (1.5% vs 0.8%; P = .08) in the FEVAR group. Mortality (2.4% vs 1.5%; P = .12) was not statistically different. On multivariable analysis, FEVAR remained independently associated with the need for postoperative transfusions when operative time was <75th percentile (adjusted odds ratio, 1.72; 95% confidence interval, 1.09-2.72; P = .02) as well as when operative time was >75th percentile for respective procedures (adjusted odds ratio, 5.33; 95% confidence interval, 3.55-8.00; P < .001).

CONCLUSIONS

Patients undergoing FEVAR are more likely than patients undergoing EVAR to receive blood transfusions postoperatively and are more likely to sustain postoperative complications. Although mortality was similar, trends toward increased cardiac and renal complications may suggest the need for judicious dissemination of this new technology. Future research with larger number of FEVAR cases will be necessary to determine if these associations remain.

Endovascular repair of a juxtarenal saccular aneurysm using the Multilayer Flow Modulator: report of the first case performed in a Public Hospital in Brazil

Endovascular treatment of abdominal aortic aneurysms (AAA), involving the exits of the renal and visceral arteries still constitutes a considerable challenge. Many different techniques have been developed over the years in attempts to surmount the difficulties presented by these cases. Techniques that have gained prominence include fenestrated or branched stents, methods involving parallel prostheses, such as the chimney, periscope and sandwich techniques, and, more recently, flow modulation with Multilayer stents. We describe a case of a complex juxtarenal saccular AAA with a high surgical risk, both according to cardiological assessment and because the patient had a difficult airway caused by a total laryngectomy for early stage laryngeal neoplasm. In view of the technical simplicity of using Multilayer stents, the presence of chronic obstructive aortoiliac disease, ostial stenosis of the renal artery and a small diameter suprarenal aorta, options involving fenestrated/branched stents and techniques involving parallel prostheses were ruled out, because of the need for multiple accesses. In view of the dilemma it presented, we describe this case as a therapeutic challenge and present the treatment option employed, which has been successful over the short term.

Open and endovascular repair of juxtarenal abdominal aortic aneurysms: a systematic review

This systematic review focuses on the 30-day mortality associated with open surgery and fenestrated endografts for short-necked (<15 mm) juxtarenal abdominal aortic aneurysms. A search for studies published in English and indexed in the PubMed and Medline electronic databases from 2002 to 2012 was performed, using "juxtarenal abdominal aortic aneurysm" and "treatment" as the main keywords. Among the 110 potentially relevant studies that were initially identified, eight were in accordance with the inclusion criteria in the analysis. Similar outcomes for open and endovascular repair were observed for 30-day mortality. No differences were observed regarding the secondary outcomes (duration of surgery, hospital stay, postoperative renal dysfunction and late mortality), except that the late mortality rate was significantly higher for the patients treated with open repair after a median follow-up of 24 months. Fenestrated endografting is a viable alternative to conventional surgery in juxtarenal abdominal aortic aneurysms with a proximal neck <15 mm.

Renal protection in juxtarenal and suprarenal aortic aneurysm surgery

Among the most important factors driving morbidity and mortality after aortic surgery is post operative renal insufficiency. The attendant metabolic derangements greatly complicate surgical care, expedite arrhythmias, and can significantly prolong hospital stay and cost. This article seeds to define factors contributory to renal complications after aortic surgery and offers a review of techniques to protect renal mass from post operative declines.

Outcomes after abdominal aortic aneurysm repair requiring a suprarenal cross-clamp

OBJECTIVE

The objective of this study was to analyze the early and late outcomes of patients who require a suprarenal aortic cross-clamp during elective open repair of an abdominal aortic aneurysm (AAA).

METHODS

Patients from 1998 to 2012 who required a suprarenal aortic cross-clamp during elective open AAA repair were reviewed. Data abstracted included demographics and comorbidities; preoperative, perioperative, and late renal function; late interventions related to AAA repair; and late mortality. A decrease in renal function was defined as a >30% decline in estimated glomerular filtration rate (eGFR) compared with the preoperative value. Primary outcomes included renal function, intervention-free survival, and overall survival.

RESULTS

During the study period, 211 patients underwent open elective or urgent AAA repair; 69 required a suprarenal cross-clamp. The mean age was 71 years, and 80% were men. The mean preoperative creatinine concentration was 1.2 mg/dL, and the mean preoperative eGFR was 66 mL/min/1.73 m2. Location of the aortic cross-clamp was suprarenal (37), supramesenteric (21), and supraceliac (11). Perioperatively, 21 patients (30%) experienced a significant decrease in eGFR; four patients required hemodialysis. Six patients had full recovery of renal function by discharge. Perioperative morbidity and mortality were 35% and 4%, respectively. At a mean follow-up of 3 years, seven patients had an eGFR significantly less than the preoperative value. Late interventions related to the AAA repair were required in eight patients. Indications included wound complication (3), anastomotic aneurysm (2), incisional hernia (1), anastomotic graft stenosis (1), and proximal aortic dilation (1). Overall 5-year intervention-free survival was 62% and overall survival 77%. Intervention-free survival was enhanced by antiplatelet use (P = .04), whereas overall survival was decreased by chronic obstructive pulmonary disease (P = .003) and perioperative pneumonia (P = .001).

CONCLUSIONS

More than a quarter of patients requiring a suprarenal cross-clamp during open AAA repair experience renal dysfunction. Late graft-related complications are few, with preoperative and perioperative pulmonary function negatively affecting overall patient survival.

Survival after repair of pararenal and paravisceral abdominal aortic aneurysms

OBJECTIVE

The objective of this study was to review our 27-year clinical experience with open proximal abdominal aortic aneurysm repairs, with a focus on long-term survival.

METHODS

A retrospective cohort study was undertaken of all patients who underwent proximal abdominal aortic aneurysm repair between 1986 and 2013 at a tertiary care referral center. Demographics, operative variables, complications, and 30-day mortality were analyzed. Postoperative acute kidney injury was analyzed by the RIFLE (Risk, Injury, Failure, Loss, End-stage renal disease)/Acute Kidney Injury Network criteria. Long-term survival was assessed through review of electronic medical records and the Social Security Death Index. Associations between demographics and complications were investigated to determine predictors of long-term survival.

RESULTS

The study identified 245 patients. Mean age was 71 years (range, 38-92 years); 69% were men, and 88% were white. Aneurysm type was juxtarenal in 127 patients (52%), suprarenal in 68 patients (28%), and type IV thoracoabdominal in 50 patients (20%). In-hospital mortality was 3.3% (eight patients), and 30-day mortality was 2.9% (seven patients). At least one major complication occurred in 64% of the patients, which included the following: acute kidney injury, 60% (persistent acute kidney injury at discharge, however, was 28%, and hemodialysis at discharge was 1.6%); major pulmonary complications, 22%; myocardial infarction, 4%; visceral ischemia, 2%; and paraplegia, 0.5%. Median follow-up was 54 months. Kaplan-Meier survival estimates were 70% at 5 years and 43% at 10 years. Variables associated with poorer survival included congestive heart failure (hazard ratio [HR], 3.5; P < .001), chronic obstructive pulmonary disease (HR, 1.8; P < .002), and increased aneurysm size at presentation (HR, 1.1; P < .013). Persistent stage 3 acute kidney injury was associated with poor long-term survival.

CONCLUSIONS

Open surgical repair of proximal abdominal aortic aneurysms can be performed with low mortality. Acute kidney injury is the most frequent complication, but the need for hemodialysis at discharge is low. Long-term survival is favorable. These data should assist in establishing benchmarks for endovascular repair of complex proximal abdominal aortic aneurysms.

Technical considerations and results of chimney grafts for the treatment of juxtarenal aneursyms

OBJECTIVE

To present our initial experience and technical considerations for the use of chimney grafts in the treatment of patients that require endovascular aneurysm repair with aortic branch preservation.

METHODS

All patients treated with a chimney procedure between October 2009 and June 2011 were included in our analyses. Chimney procedures were only performed in patients that were unsuitable for open repair and without opportunity to use fenestrated grafts (because of unsuitable anatomy or emergency operation). Open brachial or axillary access was used to deploy covered chimney grafts in the target vessels, and subsequently, a stent graft was deployed via femoral cut-down access.

RESULTS

Thirteen patients (12 males; mean age, 77.2 ± 6.2 years; mean maximal diameter, 71.4 ± 10.2 mm) underwent a chimney procedure with the preservation of 22 aortic side branches. Primary technical success was 92.3% due to occlusion of one renal artery within 24 hours. Thirty-day mortality was 0%. Infrarenal mean neck length was 2.6 mm ± 3.2 mm (range, 0-8 mm) and could be extended to 27.3 mm ± 9.9 mm (range, 18-53 mm) by the use of chimney grafts. During follow-up (median, 10.8 months; interquartile range, 7.4-19.4), one patient died from complications from mesenteric ischemia based on a stenosis of the celiac trunk attributable to the bare stent of the stent graft, and one patient died from aneurysm rupture. Other complications included late occlusion of one renal artery and a type II endoleak, which was unsuccessfully treated with coil embolization and required laparotomy. If we disregard the ruptured patient who had an enormous increase of aneurysm diameter, mean aortic aneurysm diameter reduced from 70.7 ± 10.3 mm (range, 54-89 mm) to 66.7 ± 13.9 mm (range, 48-96 mm) during follow-up (P = .13). In three patients, the aneurysm diameter decreased by more than 5 mm and in two patients, the diameter increased by more than 5 mm. The aneurysm diameter remained stable in the other eight patients.

CONCLUSIONS

Until off-the-shelf fenestrated or branched stent grafts become available, the chimney procedure offers a minimally invasive treatment option in patients requiring aneurysm exclusion with side branch revascularization. Although long-term follow-up has to be awaited, the initial results show that chimney grafts can help to decrease or stabilize the aneurysm diameter in most patients, but aneurysm rupture was not prevented in all patients.

Temporary extracorporeal axillo-iliac vascular prosthesis shunt in open repair of a pararenal aortic aneurysm

INTRODUCTION

When a long aortic clamp time is expected or when upper body to lower body collateral arteries are sparse, temporary lower body perfusion may be needed to reduce ischemic injury during supraceliac clamping in open repair of pararenal aortic aneurysms. The use of conventional extracorporeal perfusion techniques carry extra risks and is not in the armamentarium of most vascular surgeons. An axillo-femoral or -iliac shunt using a vascular prosthesis does not require the same degree of anticoagulation and causes less activation of blood components.

PRESENTATION OF CASE

A patient, who had extensive vascular stenotic disease and large bowel ischemia, was operated on for a pararenal aortic aneurysm while the lower body was perfused via a temporary extracorporeal vascular prosthesis axillo-iliac shunt. Copious backbleeding encountered while suturing the proximal anastomosis testified to the efficacy of the temporary shunt. A left hemicolectomy had to be performed for gangrene of the sigmoid colon and he needed 2 days of respiratory support; otherwise the postoperative course was uneventful.

DISCUSSION

In our case more ischemic injury than that observed might have been expected without the temporary bypass but significant backbleeding may have negated some of the beneficial effect of the shunt.

CONCLUSION

A temporary axillo-femoral or -iliac shunt prevents lower limb ischemia and provides an ample amount of collateral blood flow to the torso. It does not need to be buried subcutaneously as previously described. Occlusive balloons should be used where possible to prevent backbleeding and to further increase available collateral blood supply.

Technical factors are strongest predictors of postoperative renal dysfunction after open transperitoneal juxtarenal abdominal aortic aneurysm repair

OBJECTIVE

Juxtarenal abdominal aortic aneurysms (AAAs) have predominantly been repaired using an open technique. We present a series of patients with juxtarenal AAAs and analyze multiple factors predictive of postoperative renal dysfunction.

METHODS

Between March 2000 and September 2011, all patients in our prospectively maintained database undergoing juxtarenal AAA repair were evaluated for demographics, operative details, and in-hospital outcomes. Postoperative renal dysfunction was classified using the RIFLE (risk, injury, failure, loss, end-stage renal disease) criteria (glomerular filtration rate decrease >25%). The relationship between perioperative factors and postoperative renal dysfunction was explored using both univariate and multivariate analysis (logistic regression).

RESULTS

Of 169 patients, 76 (45%) required clamping above one renal artery, whereas 93 patients (55%) required clamping above both renal arteries. Mean (standard deviation) renal ischemia time was 29.2 (8.9) minutes (range, 12-65 minutes). Twenty-seven patients (16%) underwent adjunctive renal procedures, 19 (11.3%) required left renal vein division, and 130 (76.9%) received intraoperative mannitol. Postoperative renal dysfunction occurred in 63 patients (37.3%), with the majority (69%) resolving during hospital stay. Seven patients (4.1%) required postoperative dialysis, which was permanent in two cases. Patients who developed postoperative renal dysfunction had significantly longer mean renal ischemia times (34.7 [9.3] minutes vs 25.9 [6.6] minutes; P < .001), a higher rate of bilateral suprarenal aortic clamping (68.3% vs 47.2%; P = .008), higher rates of adjunctive renal artery procedures (26.7% vs 8.8%; P = .002), and higher rates of left renal vein division (20.6% vs 5.7%; P = .003). Logistic regression identified left renal vein division, renal ischemia time, and aortic clamp position as the strongest predictors of renal dysfunction. The use of mannitol was seen to be protective. Overall in-hospital mortality was 4.1% and was 9.5% among patients with postoperative renal dysfunction.

CONCLUSIONS

Postoperative transient renal dysfunction occurred in 37.3% of patients after open juxtarenal AAA repair, with a low incidence of dialysis and a low rate of permanent dysfunction. Technical factors including renal ischemia time, aortic clamp position, and left renal vein division are the strongest predictors of renal dysfunction. The use of intraoperative mannitol was associated with decreased postoperative renal dysfunction.

Comparison of fenestrated endovascular and open repair of abdominal aortic aneurysms not suitable for standard endovascular repair

BACKGROUND

Abdominal aortic aneurysms that are unsuitable for a standard endovascular repair (EVAR) could be considered for fenestrated endovascular repair (f-EVAR). The aim of this study was to conduct a risk-adjusted retrospective concurrent cohort comparison of f-EVAR and open repair for such aneurysms.

METHODS

All patients who underwent repair of an abdominal aortic aneurysm that was unsuitable for a standard EVAR due to inadequate neck within one institution between January 2006 and December 2010 were identified. Case notes were retrieved for clinical data, Vascular Physiological and Operative Severity Score for enUmeration of Mortality and Morbidity (V-POSSUM) score, and aneurysm morphology. Computed tomography scans were reviewed to establish aneurysm morphology.

RESULTS

A total of 107 patients were identified. The open surgery cohort included 54 patients (35 men) who were a median age of 72 years (interquartile range [IQR], 9.5; range, 60-86 years). The aortic cross-clamp was infrarenal in 20 patients, suprarenal or above in 21, and inter-renal in eight. Postoperatively, 63 major complications were noted in 30 patients, nine of whom required 16 reinterventions. Cumulative hospital stay of the cohort was 1170 days (median, 12; IQR, 13; range, 1-205 days) of which 234 days (median, 28; IQR, 36; range, 1-77 days) were in the intensive therapy unit (ITU). Perioperative mortality was 9.2% (n = 5), exactly as estimated by V-POSSUM. The f-EVAR cohort included 53 patients (47 men) who were a median age of 76 years (IQR, 11.50; range, 55-87 years). Two fenestrations and one scallop was the most frequent configuration (n = 31). Postoperatively, 37 major complications were noted in 18 patients, six requiring reintervention. Hospital stay was 559 days (median, 7; IQR, 4.5; range, 4-64 days), of which 31 days (median, 4; IQR, 10.5; range, 1-15 days) were in the ITU. Two patients died perioperatively (3.7%), resulting in an observed crude absolute risk reduction of 5.5% compared with open repair. The V-POSSUM estimated perioperative death in five patients (9.4%) in the f-EVAR cohort. In a hypothetic scenario of the f-EVAR cohort undergoing open repair, V-POSSUM estimated seven deaths (13.2%), resulting in an estimated risk-adjusted absolute risk reduction due to f-EVAR of 9.5%.

CONCLUSIONS

In this group of patients, f-EVAR reduced mortality and morbidity substantially compared with open repair and also reduced total hospital stay and ITU utilization.