Surgical repair of aneurysms involving the suprarenal, visceral, and lower thoracic aortic segments: early results and late outcome

Editor's Choice - Mortality is High Following Elective Open Repair of Complex Abdominal Aortic Aneurysms

OBJECTIVE

To evaluate the 30 day mortality of elective open complex abdominal aortic aneurysm (cAAA) repair and identify factors associated with death.

METHODS

This was a retrospective cohort study using a Targeted Vascular Module from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP). All patients undergoing elective repair for juxta- and suprarenal abdominal aortic aneurysm (AAA), or type IV thoraco-abdominal aneurysms (TAAA) from 2011 to 2017 were identified. Thirty day mortality and complication rates for open repair were established. A comparison endovascular aneurysm repair (EVAR) group was extracted from the same time period, and inverse probability weighting was applied for comparison. Logistic regression was used to identify factors independently associated with open repair mortality.

RESULTS

Of the 957 patients who underwent an elective open cAAA repair over the study period, 65 (6.8%) died. The mean age of the patient was 71.3 ± 8.0 years. The distribution by aneurysm type was 605 juxtarenal AAA (28 deaths, 4.6%); 284 suprarenal AAA (16 deaths, 9.5%), and 68 type IV TAAA (10 deaths, 14.7%). During the same time period, there were 1149 endovascular repairs for cAAA, with 43 deaths (3.7%). After inverse probability weighting and weighted logistic regression, open repair 30 day mortality yielded an OR 1.9, 95% CI 1.2-3.1, p = .01 compared with EVAR. Factors independently associated with death included more proximal extent aneurysm (referent [ref]: juxtarenal: OR 2.0 per extent increase, 95% CI 1.4-3.0, p < .001), BMI < 18.5 (OR 4.0, 95% CI 1.6-10.1, p = .003), history of severe chronic obstructive pulmonary disease (COPD) (OR 2.6, 95% CI 1.5-4.4, p = .001), more severe chronic kidney disease (CKD) (ref: none/mild): OR 1.9, 95% CI 1.2-2.8, p = .004), and age (OR 1.06/year, 95% CI 1.02-1.09, p = .002.

CONCLUSION

The 30 day mortality was 4.6% for juxtarenal AAA, 9.5% for suprarenal AAA, and 14.7% for type IV TAAA. The open repair odds of 30 day mortality was nearly twice that of endovascular repair for cAAA. Independent associations with death included BMI <18.5, more severe CKD level, more proximally extending aneurysm, age, and history of advanced COPD.

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.

Acute testicular pain secondary to a leaking abdominal aortic aneurysm (AAA)

We present the case of a 56-year-old male smoker with a background of hypertension who presented with acute onset right testicular pain secondary to a leaking abdominal aortic aneurysm. Following urgent surgical repair and a complicated intensive care recovery, the patient was discharged with no residual disability. This case highlights an atypical presentation of what is a devastating illness.

Management of Juxtarenal Aortic Aneurysms and Occlusive Disease with Preferential Suprarenal Clamping Via a Midline Transperitoneal Incision: Technique and Results

Surgical management of juxtarenal aortic (JR-Ao) aneurysms and occlusive disease may include supraceliac aortic clamping, a retroperitoneal approach, or medial visceral rotation. The authors report their results using preferential direct suprarenal aortic clamping via a midline transperitoneal incision. Between July 1, 1992, and July 31, 2001, they treated 58 patients with JR-Ao disease (44 aneurysmal, 14 occlusive) via a midline incision without medial visceral rotation. Preferential suprarenal aortic clamping was used in 53 cases (42 proximal to both renal arteries, 11 proximal to the left renal artery only) and supraceliac or supramesenteric clamping in 5 cases when there was insufficient space for an aortic clamp between the superior mesenteric artery and renal arteries. This strategy avoided mesenteric ischemia associated with supraceliac clamping in the majority of cases and afforded better exposure of the right renal artery than obtainable with a left retroperitoneal approach or medial visceral rotation. Eleven patients underwent concomitant renal revascularization. Critical adjuncts included the following: (1) selective left renal vein (LRV) division if the vein stump pressure was <35 mm Hg (suggesting sufficient renal venous collaterals existed), (2) bilateral renal artery occlusion during aortic clamping to prevent thromboembolism, (3) flushing of aortic debris before restoring renal perfusion, and (4) routine administration of perioperative intravenous mannitol and renal-dose dopamine. Patients with type IV thoracoabdominal aneurysms, ruptured aneurysms, or JR-Ao disease approached via a retroperitoneal incision (severely obese patients, re-do aortic surgery) were excluded. No patients died or required dialysis during their hospital stay. The LRV was divided in 12 (21%) cases and reanastomosed in 2 cases (elevated stump pressures). The average suprarenal clamp time was 26 minutes (range, 10–60). Postoperative serum creatinine remained >0.5 ng/dL above baseline in 3 (5%) patients. These results support suprarenal aortic clamping with a midline transperitoneal incision as the optimal strategy for treating juxtarenal aortic aneurysms and occlusive disease. The authors believe that selective left renal vein division enhances juxtarenal aortic exposure, and routine administration of renal protective agents, along with occlusion of both renal arteries during suprarenal aortic clamping, are critical adjuncts in performing these operations.

Vascular Surgery Kidney Injury Predictive Score: A Historical Cohort Study

OBJECTIVES

To develop a risk-prediction model for acute kidney injury (AKI) in patients undergoing vascular surgery.

DESIGN

A retrospective cohort study.

SETTING

A tertiary referral center.

PARTICIPANTS

Participants included 845 adult patients who underwent vascular surgery between January 3, 2003, and May 29, 2008.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The median age of patients was 72 years (interquartile range 65-80 years), and 653 patients (77%) were male. AKI developed in 258 (30.5%) patients. Patients with AKI had lower estimated glomerular filtration rates (60±21 v 72±21, p<0.001), were older (73 [68-78] years v 71 [65-80] years, p = 0.01), had a higher prevalence of hypertension (81% v 73%, p = 0.02), and were more likely to undergo emergency surgery (5% v 2%, p = 0.02). Patients with AKI also received more diuretics (p<0.001) and β-blockers (p = 0.003) prior to surgery. The multivariate AKI risk-prediction model with preoperative variables (estimated glomerular filtration rate, previous vascular interventions, use of preoperative diuretics and β-blockers, and emergency surgery) showed an area under the receiver operating characteristic curve of 0.67 (95% confidence interval, 0.628-0.710); a model with additional intraoperative variables (procedure duration, fluid balance, and plasma and platelet transfusion) had an area under the receiver operating characteristic curve of 0.72 (95% confidence interval, 0.685-0.760).

CONCLUSIONS

As AKI is a very common complication after vascular surgery, a risk-prediction model was derived to assess the likelihood of postoperative AKI. If validated in an independent cohort, this model may be used to facilitate targeted interventions in vascular surgery patients at high risk for AKI.

Spinal cord injury following thoracic and thoracoabdominal aortic repairs

Objective

To discuss the currently available approaches to prevent spinal cord injury during thoracic and thoracoabdominal aortic repairs.

Methods

We carried out a PubMed search up to 2013 using the Medical Subject Headings: “aortic aneurysm/surgery” and “spinal cord ischemia”; “aortic aneurysm, thoracic/surgery” and “spinal cord ischemia”; “aneurysm/surgery” and “spinal cord ischemia/cerebrospinal fluid”; “aortic aneurysm/surgery” and “paraplegia”. All 190 original articles satisfying our inclusion criteria were analyzed for incidence, predictors, and other pertinent variables related to spinal cord injury, and we compared the results in recent publications with those in earlier reports.

Results

The mean age of the 38,491 patients was 65.3 ± 4.9 years. The overall incidence of paraplegia and/or paraparesis was 7.1% ± 6.1% (range 0%–32%). The incidence of spinal cord injury before 2000, from 2001 to 2007, and 2008–2013 was 9.0% ± 6.7%, 7.0% ± 6.1%, and 5.9% ± 5.2%, respectively ( p = 0.019). Various predictors of spinal cord injury were identified, extent of disease being the most common. Modification of surgical techniques, use of adjuncts, and better understanding of spinal cord perfusion physiology were attributed to the decrease in postoperative spinal cord injury in recent years.

Conclusions

Spinal cord injury after thoracic and thoracoabdominal aortic repair poses a real challenge to cardiovascular surgeons. However, with evolving surgical strategies, identification of predictors, and use of various adjuncts over the years, the incidence of spinal cord injury after thoracic/thoracoabdominal aortic repair has declined. Embracing a multimodality approach offers a good insight into combating this grave complication.

Evaluation of the optimal visceral branch configuration in open thoracoabdominal aortic repair by computed tomography

BACKGROUND

In thoracoabdominal aneurysm (TAAA) repair, our technical modification of visceral reconstruction using longer cut pre-sewn side branches has provided good surgical outcomes. Here, we assessed the long-term durability and patency of revascularized branches using computed tomography (CT) to confirm the validity of our approach.

METHODS

Early and late CT evaluations were performed in 11 TAAA patients (males: 5; mean age: 60.6 years) using the Coselli graft to evaluate the position of main graft and the diverging pattern and patency of side branches. Seven of 11 were sutured in an extra-anatomical fashion using longer cut side branches.

RESULTS

In Anatomical (n = 4) and Extra-anatomical (n = 7) groups, the early patency of side branches was not significantly different. Although the late patency of right renal artery (RA) was 100% in both groups, the one of left RA was 60% in Extra-anatomical, while 100% in Anatomical. Furthermore, the main graft in Extra-anatomical was significantly posterior and leftward to the spine with left RA side branch diverging at an acute angle.

CONCLUSIONS

When a pre-sewn branched graft designed for TAAA is used, the graft should be sutured in a fashion similar to normal patient anatomy to minimize the possibility of kinking of RA side branch for the patency.

Elective open suprarenal aneurysm repair in England from 2000 to 2010 an observational study of hospital episode statistics

BACKGROUND

Open surgery is widely used as a benchmark for the results of fenestrated endovascular repair of complex abdominal aortic aneurysms (AAA). However, the existing evidence stems from single-centre experiences, and may not be reproducible in wider practice. National outcomes provide valuable information regarding the safety of suprarenal aneurysm repair.

METHODS

Demographic and clinical data were extracted from English Hospital Episodes Statistics for patients undergoing elective suprarenal aneurysm repair from 1 April 2000 to 31 March 2010. Thirty-day mortality and five-year survival were analysed by logistic regression and Cox proportional hazards modeling.

RESULTS

793 patients underwent surgery with 14% overall 30-day mortality, which did not improve over the study period. Independent predictors of 30-day mortality included age, renal disease and previous myocardial infarction. 5-year survival was independently reduced by age, renal disease, liver disease, chronic pulmonary disease, and known metastatic solid tumour. There was significant regional variation in both 30-day mortality and 5-year survival after risk-adjustment. Regional differences in outcome were eliminated in a sensitivity analysis for perioperative outcome, conducted by restricting analysis to survivors of the first 30 days after surgery.

CONCLUSIONS

Elective suprarenal aneurysm repair was associated with considerable mortality and significant regional variation across England. These data provide a benchmark to assess the efficacy of complex endovascular repair of supra-renal aneurysms, though cautious interpretation is required due to the lack of information regarding aneurysm morphology. More detailed study is required, ideally through the mandatory submission of data to a national registry of suprarenal aneurysm repair.

Renal and abdominal visceral complications after open aortic surgery requiring supra-renal aortic cross clamping

PURPOSE

The aim of this study was to assess renal or abdominal visceral complications after open aortic surgery (OAS) requiring supra-renal aortic cross clamping (SRACC).

METHODS

We retrospectively reviewed the medical records of 66 patients who underwent SRACC. Among them, 17 followed supra-celiac aortic cross clamping (SCACC) procedure, 42 supra-renal, and 7 inter-renal aorta. Postoperative renal, hepatic or pancreatic complications were investigated by reviewing levels of serum creatinine and hepatic and pancreatic enzymes. Preoperative clinical and operative variables were analyzed to determine risk factors for postoperative renal insufficiency (PORI).

RESULTS

Indications for SRACC were 25 juxta-renal aortic occlusion and 41 aortic aneurysms (24 juxta-renal, 12 supra-renal and 5 type IV thoraco-abdominal). The mean duration of renal ischemic time (RIT) was 30.1 ± 22.2 minutes (range, 3 to 120 minutes). PORI developed in 21% of patients, including four patients requiring hemodialysis (HD). However, chronic HD was required for only one patient (1.5%) who had preoperative renal insufficiency. RIT ≥ 25 minutes and SCACC were significant risk factors for PORI development by univariate analysis, but not by multivariate analysis. Serum pancreatic and hepatic enzyme was elevated in 41% and 53% of the 17 patients who underwent SCACC, respectively.

CONCLUSION

Though postoperative renal or abdominal visceral complications developed often after SRACC, we found that most of those complications resolved spontaneously unless there was preexisting renal disease or the aortic clamping time was exceptionally long.

Revascularization and rescue of a failed kidney transplant in a case of autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease is a cause of end-stage renal disease associated with abdominal aortic aneurysms. We report a patient with autosomal dominant polycystic kidney disease who received an allograft kidney and subsequently underwent treatment of an abdominal aortic aneurysm with aortic ligation and axillary-bifemoral bypass. After years of graft function, bypass thrombosis resulted in dialysis-dependent renal failure. Aortobifemoral bypass resulted in immediate restoration of allograft function despite 6 months of prior renal failure. Aortic reconstruction restored renal function to a hibernating allograft long after clinical graft failure from arterial ischemia, a phenomenon not previously reported in the literature.

Hybrid procedure in a patient with symptomatic thoraco-abdominal aneurysm and prior abdominal aortic reconstruction - case report

Open repair of thoracoabdominal aortic aneurysm is connected with high mortality and morbidity. On the other hand, endovascular treatment of thoraco-abdominal aneurysms, which started 10 years ago, reduced perioperative mortality and morbidity. However, it results in a high level of late complications. It seems that an interesting solution to the problem is a hybrid procedure, which allows late complications to be reduced with acceptable levels of operative mortality and morbidity. This case report presents the use of a hybrid procedure in treatment of symptomatic thoraco-abdominal aneurysm in a patient with prior abdominal aortic reconstruction. In the first stage the patient underwent open revascularization of visceral vessels of the aorta. One week later a thoraco-abdominal stent-graft was implanted. The perioperative and postoperative period was uncomplicated. Two months after the second intervention the patient returned to work. Control imaging conducted 30 and 90 days after the procedure confirmed patency of all revascularized vessels and did not reveal any graft-related complications. The hybrid procedure seems to be an interesting alternative for open and endovascular repair of thoraco-abdominal aneurysms because it combines the advantages of open and endovascular repair. It also gives an opportunity to perform the procedure within a reasonable period of time from diagnosis of symptomatic thoraco-abdominal aneurysm.

Predictors of early and late mortality following open extent IV thoracoabdominal aortic aneurysm repair in a large contemporary single-center experience

OBJECTIVE

The primary purpose of this study was to examine outcomes following open repair of extent IV thoracoabdominal aortic aneurysms (TAAAs) at a single university hospital. As a secondary aim, comparison was made to patients who underwent open abdominal aortic aneurysm (AAA) repair with supraceliac clamping but without left renal artery bypass to assess the effect of left renal artery bypass on outcomes.

METHODS

Patients undergoing open extent IV TAAA repair from 1998 to 2008 were identified (n = 108). Primary outcomes were 30-day and long-term survival. Secondary outcomes were major complication, renal failure, and postoperative change in renal function. A second analysis was performed, comparing patients undergoing extent IV TAAA repair with patients undergoing AAA repair with supraceliac clamping but without left renal artery bypass (n = 50).

RESULTS

Eighty-three men (76.9%) and 25 women (23.1%), with a mean age of 72.9 years, underwent open extent IV TAAA repair. Nine patients (8.3%) were ruptured. Mean aneurysm maximal diameter was 6.5 ± 1.3 cm. Supraceliac and left renal ischemic times were 22.9 ± 9.3 and 40.6 ± 16.2 minutes, respectively. Six patients (5.6%) died at 30 days. The only predictor of 30-day mortality was decreased preoperative estimated glomerular filtration rate (eGFR) (P = .044 by multivariate analysis; and P = .011 by univariate analysis). One-year and 5-year survival rates were 87% and 50%, respectively. Patients with a history of cerebrovascular disease (P = .001) and postoperative renal insufficiency (P = .034) had increased long-term mortality by log-rank test. Twenty-five (25.3%) patients sustained a postoperative decrease in renal function, while 19 (19.2%) patients had an improvement in renal function. There was no difference in 30-day mortality (5.6% vs 6.0%; P = 1.000), 5-year survival (50% vs 48%; P = .886), major complications (37.0% vs 38.0%; P = 1.000), renal failure (6.1% vs 0%; P = .215), or postoperative change in renal function, in patients undergoing extent IV TAAA repair vs AAA repair with supraceliac clamping but without left renal artery bypass.

CONCLUSIONS

Open extent IV TAAA repair can be performed with low morbidity and mortality rates. The performance of left renal artery bypass does not appear to contribute to the morbidity and mortality of extent IV TAAA repair. While decreased preoperative eGFR appears to increase the risk of 30-day mortality, a history of cerebrovascular disease and postoperative renal insufficiency appear to increase the risk of long-term mortality. Finally, open extent IV TAAA repair not uncommonly improves renal function.

Contemporary results for open repair of suprarenal and type IV thoracoabdominal aortic aneurysms

Background

Endovascular and hybrid procedures are not yet widely established in the management of type IV thoracoabdominal aortic aneurysm (TAAA). Open surgery remains the treatment of choice until the long-term outcomes of these novel techniques are known.

Methods

This study reviewed a 10-year experience of open repair of non-ruptured type IV and suprarenal TAAA. All procedures were performed using a totally abdominal approach with supracoeliac clamping of the aorta.

Results

There were 53 patients (31 men; 58 per cent) of median age 69 (range 54–82) years. Forty-four patients had a type IV TAAA and nine a suprarenal aneurysm. Three patients (6 per cent) died within 30 days and the 12-month mortality rate for patients followed for at least 1 year was 6 per cent (three of 49). Ten patients (19 per cent) had a cardiac complication, 20 (38 percent) a respiratory complication, three (6 percent) required early reoperation, and one patient (2 percent) developed permanent paraplegia. There was one late death resulting from an aneurysm-related complication.

Conclusion

Open repair of suprarenal aneurysms and type IV TAAA may be undertaken using a totally abdominal approach with acceptable levels of morbidity and mortality.

Complex Abdominal Aortic Pathologies: Operative and Midterm Results after Pararenal Aortic Aneurysm and Type IV Thoracoabdominal Aneurysm Repair

The aim of the study was to describe the clinical outcome of pararenal aortic aneurysm (PAAA) and type IV thoracoabdominal aneurysm (TAAA) repair, with special consideration placed on disease-related complications and midterm follow-up. Data were collected retrospectively between 1997 and 2004 for patients with PAAA or type IV TAAA repair. Comorbidities, operative details, and early and late outcome were analyzed to predict disease-related complications. During the study period, 63 patients (33 PAAAs, 30 type IV TAAAs) underwent aortic repair. The 30-day mortality rate of 7.9% was acceptable for complex aortic entities compared with other series. The morbidity for cardiac events was 3.2%, for pulmonary complications 17.5%, and the need for reoperation was 14.3%. With regard to disease-related complications, two patients (3.2%) required dialysis and one patient (1.6%) developed paraplegia (spinal cord ischemia) after type IV TAAA repair. Complex aortic repair for PAAAs and type IV TAAAs showed acceptable perioperative mortality, morbidity, and midterm survival rates. Patients with type IV TAAAs suffered more major complications, such as postoperative dialysis or spinal cord ischemia.

Endovascular treatment for visceral vessel complication after branched graft replacement: initial results

OBJECTIVE

The objective of our study was to retrospectively assess the safety and efficacy of endovascular treatment for branch stenosis or obstruction after branched graft replacement in patients with thoracoabdominal aortic aneurysm or aortic arch aneurysm.

MATERIALS AND METHODS

Seven patients (all men; median age, 62 years; age range, 19-79 years) who had undergone aortic surgery using branched grafts between March 2004 and January 2007 were treated. Diagnosis was established on dynamic contrast-enhanced CT or angiography. A self- or balloon-expandable stent was placed after predilatation with a balloon catheter and, if necessary, thrombolysis was also performed. Stent patency was assessed on thin-slice axial images obtained during the arterial phase on dynamic contrast-enhanced CT.

RESULTS

Seven lesions (one celiac artery, two left subclavian arteries, and four renal arteries) were treated. The time between the surgery and treatment was 0-3 days for patients with abdominal lesions and 20-41 days for those with thoracic lesions. Stent placement was successful in five of the seven patients. In one patient, insertion of the stent delivery system was unsuccessful; in the other patient, the stent was not completely expanded. The clinical symptoms and abnormal laboratory data improved in all patients with successful procedures. No restenosis was observed on imaging follow-up, with a median patency of 104 days (range, 5-1,218 days) during clinical follow-up (range, 37-1,218 days; median, 135 days).

CONCLUSION

Endovascular repair can be an alternative treatment for visceral vessel complications of branched grafts, especially in obstructed but peripherally patent branches.

Perioperative statin therapy and renal outcomes after major vascular surgery: a propensity-based analysis

OBJECTIVE

To evaluate how the presence and timing of statin therapy affect perioperative renal outcomes after major vascular surgery.

DESIGN

Retrospective cohort study.

SETTING

Surgical intensive care unit at a single academic medical center.

PARTICIPANTS

Patients undergoing major vascular surgery between July 2004 and October 2005.

MEASUREMENTS AND MAIN RESULTS

The presence and timing of perioperative statin administration and the propensity for receiving such therapy were noted. Renal outcomes, lengths of stay, and mortality were reviewed. One hundred fifty-one procedures were performed. Eighty-nine patients (59%) received statin therapy. There was no evidence for renal protection with perioperative statin therapy (Delta creatinine 0.2 mg/dL v 0.2 mg/dL, p = 0.41; acute renal injury/acute renal failure 8% v 6%, p = 1.00; renal replacement therapy 3% v 3%, p = 1.00; all statin v no statin, respectively). With the possible exception of early reinstitution of statin therapy in chronic statin users, subgroup analyses failed to confirm an association between statin timing and prevention of postoperative renal dysfunction.

CONCLUSIONS

In the present investigation, neither the presence nor timing of perioperative statin therapy was associated with improved renal outcomes in patients undergoing a range of major vascular procedures. A possible exception is early postoperative reinitiation of statin therapy in chronic statin users. The discrepant results of available literature preclude a definitive statement on the use of statin therapy as a means of preventing postoperative renal dysfunction. An adequately powered prospective trial is needed before advocating the routine use of statin therapy for perioperative renal protection.

Endovascular Repair of Thoracoabdominal Aneurysms

Background— Morbidity and mortality after conventional repair of thoracoabdominal aneurysms remain high. Alternative techniques have been proposed and are the subject of this report.

Methods and Results— Endovascular grafts that have a means of incorporating the visceral vessels into the aortic repair were divided into devices with fenestrations and those with formal branches. Hybrid procedures whereby an extra-anatomic bypass procedure is used to provide inflow to the renal and mesenteric arteries followed by aortic relining with stent grafts were reviewed and tabulated. A description of the techniques and review of the current results are provided. Only 4 series with >10 cases of hybrid procedures have been published. The experience with such a procedure suggests feasibility, but most reports describe a persistently high risk of mortality (up to 25%). Larger series of fenestrated stent grafts to treat juxtarenal aneurysms have been published, and intermediate-term results confirm the safety and efficacy of the procedure. A larger multicenter trial is under way. Other pure endovascular methods have been used to treat thoracoabdominal aneurysms with both reinforced fenestrations and directional branches. Without counting small series (<10 cases), 2 series exist with ≈100 cases that noted perioperative mortality rates between 3% and 6%, without evidence of late ruptures.

Conclusions— Endovascular repair of thoracoabdominal aneurysms is feasible and is associated with relatively low perioperative mortality. Several methods of visceral vessel incorporation have been described. Because of persistently high mortality, hybrid procedures will likely be relegated to nonsurgical and nonendovascular patients with sizable aneurysms. Endografts with branches continue to evolve and will be assessed in the context of clinical trials.

Early Results after Staged Hybrid Repair of Thoracoabdominal Aortic Aneurysms

BACKGROUND

The morbidity and mortality rates associated with open thoracoabdominal aortic aneurysm (TAAA) repair are substantial. This study was designed to review our early experience with the hybrid endovascular and, or open approach for TAAA repair.

STUDY DESIGN

Patients undergoing elective hybrid repair of their TAAAs were retrospectively reviewed.

RESULTS

Seventeen patients (mean age 69+/-15 years, male, 76%) underwent visceral and renal revascularization as the first stage of their hybrid repair. The Crawford extent included: II, 2; III, 8; and IV, 7. Perioperative mortality and complication rates after the first stage were 24% and 25%, respectively; the mean intensive care unit stay and total length of stay were 7+/-12 days (range 1 to 45 days) and 22+/-33 days (range 3 to 100 days), respectively. The endovascular aneurysm repair or second stage procedure was performed in 12 of 13 (92%) of the surviving patients, with a mean of 27+/-27 days (range 6 to 99 days) between the procedures. Two patients experienced intraoperative complications during the second stage, but there were no deaths or additional postoperative complications. Patients did not require the intensive care unit, and the overall mean length of stay after the second stage was 2+/-2 days (range 1 to 5 days). The mean postoperative followup among the 11 patients completing both stages was 8+/-12 months (range 1 to 15 months). The primary patency rate for the visceral and renal bypasses was 96% (54 of 56).

CONCLUSIONS

The hybrid approach for patients with TAAAs may reduce complications in the average, low-risk patient and may extend the indications for repair to patients considered higher risk based on age, comorbidities, or anatomic considerations.

Current Treatment of Peripheral Arterial Disease

Despite advances in medical therapies to help prevent the development of atherosclerosis and improve the management of patients with established peripheral arterial disease (PAD), the prevalence of PAD and associated morbidity remains high. Over the past decade, percutaneous revascularization therapies for the treatment of patients with PAD have evolved tremendously, and a great number of patients can now be offered treatment options that are less invasive than traditional surgical options. With the surgical approach, there is significant symptomatic improvement, but the associated morbidity and mortality preclude its routine use. Although newer percutaneous treatment options are associated with lower procedural complications, the technical advances have outpaced the evaluation of these treatments in adequately designed clinical studies, and therapeutic options are available that may not have been rigorously investigated. Therefore, for physicians treating patients with PAD, an understanding of the various therapies available, along with the inherent benefits and limitations of each treatment option is imperative as a greater number of patients with PAD are being encountered.

Anesthesia and renal disease

PURPOSE OF REVIEW

To present and interpret the relevant research (Jan 2001-Feb 2002) which has the most important implications for clinical anesthesiology as regards the prevention of perioperative renal dysfunction and the anesthetic management of patients with renal disease.

RECENT FINDINGS

Prolonged sevoflurane anesthesia with fresh gas flow less than 1 l min is unlikely to lead to clinically significant renal injury. When used as maintenance agents for patients undergoing coronary artery bypass grafting, sevoflurane anesthesia at a fresh gas flow of 3 l min, isoflurane and propofol are associated with similar rates of postoperative renal dysfunction. Less compound A is produced with smaller soda lime containers. High flow sevoflurane anesthesia (fresh gas flow of 4-6 l min) in combination with perioperative ketorolac is unlikely to lead to renal injury. Chronic treatment with angiotensin-converting enzyme inhibitors is associated with an increased incidence of postoperative renal impairment in patients undergoing elective aortic surgery. Thoracic epidural anesthesia and postoperative analgesia are associated with a decreased incidence of renal failure in patients undergoing coronary artery bypass grafting. Compared with open surgical repair, endovascular repair of aortic aneurysm is associated with less renal injury.

SUMMARY

Sevoflurane anesthesia at low or high fresh gas flow rates is probably no more injurious to the kidneys than other commonly used maintenance agents. Chronic angiotensin-converting enzyme inhibition may increase perioperative renal dysfunction. The use of thoracic epidural anesthesia and analgesia may reduce the incidence of postoperative renal failure.

Optimal End-Organ Protection for Thoracic and Thoracoabdominal Aortic Aneurysm Repair Using Deep Hypothermic Circulatory Arrest

BACKGROUND

Despite the advent of numerous protective strategies, thoracic and thoracoabdominal aortic replacement remains a high risk. While mortality rates have improved over the last 15 years, the incidence of adverse outcomes (including stroke, renal failure, and paraplegia, as well as death) remains at 13% to 30% in all published series. The use of deep hypothermic cardiopulmonary bypass with circulatory arrest has been associated with high morbidity in the past; however, we report a single surgeon's experience of improved end-organ protection with low morbidity and mortality utilizing this technique.

METHODS

One hundred seventy-three consecutive patients with descending thoracic and thoracoabdominal aneurysms were operated on between April 1995 and March 2005. Hypothermic (15 degrees C) cardiopulmonary bypass with circulatory arrest and open proximal anastomosis were utilized in all subjects. Visceral arteries were uniformly reimplanted as an island while additional renal artery bypasses were performed as required. Lower intercostals and lumbar arteries were aggressively reimplanted or preserved at the aortic anastomosis. No other adjuncts for spinal cord protection were routinely employed.

RESULTS

Sixty-three patients with isolated descending thoracic aortic aneurysms and 27 patients with extent I, 49 with extent II, 20 with extent III, and 14 with extent IV thoracoabdominal aortic aneurysms underwent operative repair. Ninety percent of cases were elective while 10% were urgent or emergent. There were seven hospital deaths, and the hospital mortality was 4.0%. Operative complications included stroke in seven patients (4.1%), paraplegia in four (2.4%), including 0 of 62 ambulatory patients with isolated thoracic aneurysm repairs, and acute renal failure requiring dialysis in two of 168 operative survivors that were not dialysis-dependent before surgery.

CONCLUSIONS

Deep hypothermic circulatory arrest allows replacement of complex aortic pathology with low mortality. End-organ protection is excellent with lower incidences of dialysis-dependent renal failure and paraplegia than are reported with other currently used surgical techniques.

Preservation of Renal Function Utilizing Hypothermic Circulatory Arrest in the Treatment of Distal Thoracoabdominal Aneurysms (Types III and IV)

Although left heart bypass and hypothermia are often used in the performance of type I and type II thoracoabdominal aneurysms (TAAs), most of these more distal aneurysms are done utilizing the clamp and sew technique. Renal failure occurs between 8.6% to 39% in recent series of patients following surgery for type III and IV TAAs. The purpose of this study was to determine whether the use of hypothermic circulatory arrest in these cases would serve to protect renal function. All patients were operated on using hypothermic circulatory arrest. The kidneys were perfused with cold blood during the procedures, and renal artery bypasses were aggressively used (when stenoses greater than 50% were observed). The series describes 33 consecutive patients with type III and IV TAAs who were operated on utilizing hypothermic circulatory arrest with a core temperature of 15 degrees centigrade. All visceral and renal arteries were individually perfused; 20 patients had bypass grafts of their renal artery stenoses. Although six patients had renal failure preoperatively, only one developed postoperative renal failure. This was the patient who was operated on as an emergency for severe abdominal pain, back pain, and acidosis who was also the only hospital death. Of the remaining five patients with elevated creatinines preoperatively, four had postoperative decrease of the serum creatinine. One patient developed paraparesis and one developed a stroke. The median length of stay was 8 days. Consideration should be given to the use of hypothermic circulatory arrest in type III and IV TAAs for the preservation of renal function and improved overall results.

Effects of statins on renal function after aortic cross clamping during major vascular surgery

Ischemic reperfusion injury is an important cause of renal dysfunction after major vascular surgery and increases postoperative morbidity and mortality. The aim of the present study was to assess the effect of statins on renal function in patients at high risk for renal dysfunction, that is, those who underwent suprarenal aortic cross clamping-declamping. Seventy-seven patients (28 statin users, 57 men; mean age 69 +/- 8 years) with normal preoperative renal function requiring suprarenal aortic cross clamping-declamping during vascular surgery from 1995 to 2005 were studied. Creatinine levels were obtained before surgery and on days 1, 2, 3, 7, and 30 after surgery. An analysis-of-variance model for repeated measurements was applied to compare creatinine levels between statin users and nonusers, with adjustment for clamping time and blood loss. There were no differences in baseline clinical characteristics, preoperative creatinine levels (0.93 vs 0.96 mg/dl, p = 0.59), and glomerular filtration rate (79 vs 73 ml/min, p = 0.1). Postoperative creatinine levels during the 30 days after surgery were significantly lower in statin users than in nonusers (analysis-of-variance p <0.01, 1.17 vs 1.98 mg/dl). Postoperative hemodialysis was required (temporarily) in 7 patients (9.1%), all statin nonusers. These findings suggest an association between statin use and preserved renal function after suprarenal aortic clamping.

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 x 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.

Aneurisma tóraco-abdominal inflamatório

Os autores relatam o caso de um paciente apresentando aneurisma tóraco-abdominal tipo IV de etiologia inflamatória. Esse paciente foi submetido à correção cirúrgica eletiva através de incisão tóraco-abdominal, rotação medial das vísceras, com dificuldade, devido às aderências, e utilização de perfusão visceral durante o pinçamento supracelíaco, com um circuito de circulação extracorpórea modificado.

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 Thoracoabdominal Aneurysm Type IV

BACKGROUND

Thoracoabdominal aneurysm type IV (TAA IV) represents only a minority of aortic aneurysms, but as it is an entirely abdominally located aneurysm, vascular surgeons are likely to see such aneurysms in their practice. The current surgical management of TAA IV is reviewed.

METHODS

A PubMed/Medline-literature search for TAA IV.

RESULTS AND CONCLUSIONS

A detailed preoperative evaluation to determine the rupture and operative risk is required. A threshold size of 5.5-6 cm is recommended for elective repair of TAA IV, which then is adjusted for age and other risk factors. Operative simplicity with the clamp and sew approach to obtain a short aortic cross-clamp time seems to have most support in the literature. The necessity of adjunct treatment to prevent visceral and spinal cord ischemia seems to be needed rarely. Uncomplicated repair has a minimal risk of neurological injury and a low risk of renal failure requiring dialysis in patients without preoperative renal dysfunction or renal artery stenosis. The role of endovascular repair of these aneurysms remains to be established.

Endovascular Abdominal Aortic Aneurysm Repair: Does Gender Matter?

Substantial differences across genders have been documented for the natural history and clinical course of cardiovascular diseases. This study's objective is to compare preoperative characteristics, intraoperative events, and postoperative outcomes in men and women undergoing endovascular abdominal aortic aneurysm repair (EVAR). We hypothesized that despite gender anatomic specificities, EVAR may achieve similar results across genders. We included 241 consecutive patients who underwent elective EVAR at our institution from December 1996 through May 2003. Demographic variables and comorbidities were collected by chart review, and intraoperative events were from surgical notes. Baseline anatomic characteristics were evaluated on the last preoperative computed tomography (CT) scan. Radiologic outcomes were evaluated on all postoperative CT scans, and clinical follow-up information was abstracted from charts. Women constituted 12% (n = 29) of our cohort and were older than men (79.9 vs. 74.9 years, p = 0.0003). When compared to men, they had aneurysms with similar diameter (54.1 vs. 55.5 mm, p = 0.491) but narrower (23.1 vs 25.5 mm, p < 0.0001) and shorter (18.9 vs. 30.4 mm, p < 0.0001) proximal necks. Female iliac arteries were narrower (9.6 vs. 11.4 mm, p < 0.0001), with higher calcification scores (2.5 vs. 2.3, p = 0.047) but lower tortuosity indexes (1.2 vs. 1.3, p = 0.0001). Additional access maneuvers were more frequent in women: iliac access angioplasty (31% vs. 10.9%, = p = 0.007), uni-iliac conversion (13.8% vs. 1.4%, p = 0.005), and iliac "chimney" conduit (12.1% vs. 1.2%, p = 0.0001). There was a trend toward longer fluoroscopy time in women (34.6 vs. 26.9 min, p = 0.056). The following postoperative outcomes at 24 months were similar in women and men: freedom from endoleak (63.4% vs. 72.7%, p = 0.74), reintervention rate (28% vs. 24.5%, p = 0.878), aneurysm shrinkage (24.3% vs. 68.7%, p = 0.199), aneurysm expansion (0% vs. 3%, p = 0.213), and survival (92.9% vs. 84.3%, p = 0.341). There was a trend toward higher rates of neck dilation relative to preoperative diameter in women (48.5% vs. 16% at 12 months, p = 0.059) and toward lower limb patency rates in men (100% vs. 92.8%, p = 0.098). In sum, women have shorter proximal necks and smaller and more calcified iliac arteries, which increases the necessity of access-related additional maneuvers. Despite being older and having a less favorable anatomy, women can expect similar technical and clinical outcomes after EVAR.

Hypothermic cardiopulmonary bypass and circulatory arrest in the management of extensive thoracic and thoracoabdominal aortic aneurysms

Hypothermic cardiopulmonary bypass, usually in combination with an interval of circulatory arrest, was used for the treatment of 211 patients with extensive thoracic or thoracoabdominal aortic disease during a 17-year interval. Profound hypothermia, distal perfusion, and intravenous methylprednisolone and thiopental were used for neuroprotection. No other technique or other adjunctive agents were used. The 30-day mortality rate was 7.1% (15 patients). It was 40% (8 of 20) for patients undergoing emergent operations for aortic rupture or acute dissection and 3.7% (7 of 191) for all other patients (P<0.001). Paraplegia occurred in 5 and paraparesis in 1 of the 205 operative survivors whose lower limb function could be assessed postoperatively (2.9%). Of the 121 survivors with thoracoabdominal aortic disease, paraplegia occurred in 1 of 38 patients with Crawford type I disease (2.6%), 2 of 49 with type II (4.1%), and 2 of 34 with type III (5.9%). Paralysis developed in 1 (1.7%) of the 58 patients who underwent aortic dissection. Renal dialysis was required in 6 (2.9%) of the 205 operative survivors, prolonged inotropic support (>48 hours) in 23 (11%), reoperation for bleeding in 10 (5%), mechanical ventilation (>48 hours) in 50 (24%), and tracheostomy in 21 (10%). Four (1.9%) patients sustained a stroke. Hypothermic cardiopulmonary bypass provides safe and substantial protection against paralysis, and renal, cardiac, and visceral organ system failure that equals or exceeds that of other currently used techniques but without the need for other adjuncts.

Renal dysfunction and prolonged visceral ischaemia increase mortality rate after suprarenal aneurysm repair

BACKGROUND

Elective juxtarenal abdominal aneurysm repair has a significantly lower mortality rate than suprarenal repair. Identification of factors affecting outcome may lead to a reduction in mortality rate for suprarenal repair.

METHODS

Data were collected prospectively between 1993 and 2000 for 130 patients who underwent type IV thoracoabdominal aneurysm (TAA) repair and 44 patients who had juxtarenal aneurysm (JRA) repair. Preoperative risk factors and operative details were compared between groups and related to outcome after TAA repair (there were only two deaths in the JRA group).

RESULTS

The in-hospital mortality rate was significantly higher following TAA repair (20.0 per cent; 26 of 130 patients) than JRA repair (4.5 per cent; two of 44). Raised serum creatinine concentration was the only preoperative factor (P = 0.013) and visceral ischaemia the only significant operative factor (P = 0.001) that affected mortality after TAA repair.

CONCLUSION

JRA repair was performed with similar risks to those of infrarenal aneurysm repair. Impaired preoperative renal function was related to death following TAA repair and conservative treatment should be considered for patients with a serum creatinine level above 180 micromol/l. Reducing the duration of visceral ischaemia might improve outcome.

Coronary and carotid artery disease in patients with degenerative aneurysm of the descending thoracic or thoracoabdominal aorta: prevalence and impact on operative mortality

From January 1, 1995 to July 31, 2000, a total of 133 patients underwent elective surgical treatment for degenerative aneurysm of the descending thoracic (n = 45) or thoracoabdominal (n = 88) aorta. There were 116 men (87%) and 17 women (13%) with a mean age of 66.4 +/- 8.7 years (range, 39 to 84 years). Sixteen patients (12%) died in the immediate postoperative period. Thirteen patients (10%) had already undergone myocardial revascularizaton. Thirty-five patients (26%) presented clinical symptoms of coronary artery disease. Preoperative coronary arteriography was performed in 84 (63%) patients, demonstrating normal findings or clinically insignificant lesions in 48 patients (57%), single-vessel lesions (>70% reduction in diameter) in 19 patients, two-vessel lesions in 12 patients, and three-vessel lesions in 5 patients. On the basis of these findings, myocardial revascularization was performed before aortic repair in 11 patients. The total number of myocardial revascularization procedures in this series was 24 (18%). Four patients had previously undergone a total of 6 carotid endarterectomy procedures. Routine duplex ultrasound demonstrated significant carotid artery lesions in 12 patients (9%). Ten of these patients (8%) underwent carotid endarterectomy. The total number of carotid endarterectomy procedures in this series was 16 in 14 patients. The prevalence of coronary and carotid lesions in patients indicated for elective treatment for degenerative aneurysm of the descending thoracic or thoracoabdominal aorta was similar to that observed in patients presenting degenerative aneurysm of the infrarenal abdominal aorta. Univariate analysis demonstrated that coronary and carotid lesions with or without treatment are a significant risk factor for mortality following surgical repair of degenerative aneurysm of the descending thoracic or thoracoabdominal aorta. This finding suggests that routine preoperative coronary arteriography and duplex ultrasound are warranted.

Endovascular stent-graft repair of descending thoracic aortic aneurysms: the nursing implications for care

Endovascular repair of descending thoracic aortic aneurysms is a minimally invasive procedure performed with the patient under epidural or spinal anesthesia as an alternative to the conventional left thoracotomy repair. A Dacron graft, similar to the one used in the conventional repair, is placed in the thoracic aorta with fluoroscopic guidance via the femoral or iliac artery. Once the graft is in place, the aneurysm is excluded from the general circulation, thereby preventing rupture. Endovascular repair is currently being offered at selected sites to patients who otherwise would not be candidates for surgical repair due to severe comorbidities such as cardiac, pulmonary, or renal disease. As both the technique and the devices become perfected, endovascular stent-graft repair of descending thoracic aortic aneurysms will most likely be offered as a method of treatment in both high- and low-risk patients who are anatomic candidates for the procedure. This article describes the conventional repair and the endovascular repair of descending thoracic aneurysms. It discusses the implications for nursing care in the preoperative and postoperative settings and defines guidelines for the long-term follow-up of patients who undergo endovascular repair.

Gender differences in endovascular abdominal aortic aneurysm repair with the AneuRx stent graft

OBJECTIVE

The objective of this study was to evaluate gender differences in the selection, procedure, and outcome of endovascular abdominal aortic aneurysm repair (EVAR).

PATIENTS

Between October 1996 and January 2001, 378 patients were evaluated for EVAR and 189 patients underwent EVAR with the Medtronic AneuRx stent graft at a single center.

RESULTS

Women constituted 17% of patients considered for EVAR. Their eligibility rate (49%) did not differ significantly from that of men (57%), and they constituted 14% of patients who underwent EVAR (26/189). Women who underwent EVAR were older (77.9 +/- 6.3 years versus 73.1 +/- 8.1 years; P <.005) with a higher rate of chronic obstructive lung disease (50% versus 28%; P <.05). Maximal aneurysm diameter (57.2 +/- 10.9 mm versus 57.8 +/- 9.4 mm; not significant) did not differ between men and women. Mean diameters of the proximal neck (20.4 +/- 2.3 mm versus 22.3 +/- 2.0 mm; P <.01), common iliac arteries (11.4 +/- 1.2 mm versus 13.5 +/- 3.6 mm; P <.001), and external iliac arteries (7.9 +/- 0.7 mm versus 9.4 +/- 1.4 mm; P <.001) were all smaller in women, and abdominal aortic aneurysm/neck diameter ratio was larger (2.82 +/- 0.59 versus 2.60 +/- 0.49; P <.05). The length of the proximal aortic neck was shorter in women (20.7 +/- 8.2 mm versus 24.5 +/- 11.8 mm; P <.05). Women had significantly more intraoperative complications (31% versus 13%; P <.05), primarily related to arterial access, and needed more frequent arterial reconstruction (42% versus 21%; P <.05), without a difference in postoperative mortality rate (0/26 versus 2/163; not significant) and complication rate (23% versus 20%: not significant). During a follow-up period of 13.8 +/- 11.7 months, no gender-related difference was found in survival rate, endoleak rate, or reintervention rate or in the rate of change in aneurysm diameter or volume.

CONCLUSION

Eligibility rates of women for EVAR are similar to those of men. Women are at an increased risk for access-related complications during EVAR, but outcome is equivalent to that of men.

Safety and efficacy of hypothermic cardiopulmonary bypass and circulatory arrest for operations on the descending thoracic and thoracoabdominal aorta

BACKGROUND

Hypothermic cardiopulmonary bypass with circulatory arrest is an important adjunct for operations on the distal aortic arch and the descending thoracic and thoracoabdominal aorta. Its safety and efficacy compared with other techniques (eg, simple aortic clamping, partial cardiopulmonary bypass, and regional hypothermia) are not clearly established.

METHODS

One hundred sixty-one patients (ranging from 20 to 83 years old) with descending thoracic or thoracoabdominal aortic disease had resection and graft replacement of the involved aortic segments using hypothermic cardiopulmonary bypass usually with intervals of circulatory arrest (mean interval, 38 minutes).

RESULTS

The 30-day mortality rate was 6.2% (10 patients). It was 41% (7 of 17) for patients having emergent operations (rupture or acute dissection) and 2.1% (3 of 144) for all other patients (p < 0.001). The 90-day mortality rate was 11.8% (19 patients). Paraplegia occurred in 4 and paraparesis in 1 of the 156 operative survivors whose lower limb function could be assessed postoperatively (3.2%). Among the 91 survivors with thoracoabdominal aortic disease, early paraplegia occurred in 1 of 33 patients with Crawford type I disease, 0 of 34 with type II disease, and 2 of 24 with type III disease. One patient (type II disease) had development of paraplegia on the tenth postoperative day. None of the 50 patients with aortic dissection experienced paralysis. Renal dialysis was required in 4 (2.5%) of the 157 operative survivors, prolonged inotropic support (> 48 hours) in 17 (11%), reoperation for bleeding in 8 (5%), mechanical ventilation (> 48 hours) in 31 (20%), and tracheostomy in 13 (8%). Three patients (1.9%) sustained a stroke.

CONCLUSIONS

Hypothermic cardiopulmonary bypass provides safe and substantial protection against paralysis and renal, cardiac, and visceral organ system failure that equals or exceeds that of other currently used techniques but without the need of other adjuncts.

Factors affecting outcome in proximal abdominal aortic aneurysm repair

Sixty-five consecutive patients undergoing nonemergent repair of an abdominal aortic aneurysm (AAA) originating above the visceral and/or renal arteries were studied to determine operative results and identify factors influencing outcome of proximal AAA repair. Factors associated with postoperative morbidity were analyzed using multivariate analysis. There were no postoperative deaths, paraplegia/paraparesis, or symptomatic visceral ischemia. Proximal AAA repair can be accomplished with acceptable mortality. If renal artery bypass or reimplantation is anticipated, cold renal perfusion may protect against renal dysfunction. Postoperative pulmonary dysfunction can be reduced by avoiding radial division of the diaphragm.

An endovascular system for thoracoabdominal aortic aneurysm repair

PURPOSE

To describe a stent-graft system for endovascular repair of thoracoabdominal aortic aneurysm (TAAA) that preserves side branch perfusion.

TECHNIQUE

The modular endograft system includes 3 components. The primary stent-graft is custom-made from conventional graft fabric and Gianturco Z-stents. Covered nitinol Smart Stents are used for the visceral and renal extensions, and the distal extension is made from a modified Zenith system. With the supine patient under general anesthesia, the components are delivered sequentially through surgically exposed femoral and right brachial arteries in an operation that requires prolonged periods of magnified high-resolution imaging. This system was first used in a 76-year-old man with a contained rupture of a supraceliac ulcer and a large abdominal aortic aneurysm ending proximally at the celiac artery. The endograft was implanted successfully, but the patient developed paraplegia on day 2; imaging documented an excluded aneurysm and excellent flow through the endograft and all prosthetic branches.

DISCUSSION

Endovascular repair of TAAA appears to be feasible. If there are no serious, specific, unavoidable complications, the potential advantages are enormous.