The value of late computed tomographic scanning in identification of vascular abnormalities after abdominal aortic aneurysm repair

Visceral segment aortic thrombus is associated with proximal aortic degeneration after infrarenal abdominal aortic aneurysm repair

OBJECTIVE

To identify predictors of aortic aneurysm formation at or above an infrarenal abdominal aortic aneurysm repair.

METHODS

A total of 881 infrarenal abdominal aortic aneurysm repairs were identified at a single institution from 2004 to 2008; 187 of the repairs were identified that had pre-operative and post-operative computed tomography imaging at least one year or greater to evaluate for aortic degeneration following repair. Aortic diameters at the celiac, superior mesenteric, and renal arteries were measured on all available computed tomographic scans. Aortic thrombus and calcification volumes in the visceral and infrarenal abdominal aortic segments were calculated. Multivariable modeling was used with log transformed variables to determine potential predictors of future aortic aneurysm development after infrarenal abdominal aortic aneurysm repair.

RESULTS

Of the 187 patients in the cohort, 100 had an open abdominal aortic aneurysm repair while 87 were treated with endovascular repair. Proximal aortic aneurysms developed in 26% (n = 49) of the cohort during an average of 72 ± 34.2 months of follow-up. After multivariable modeling, visceral segment aortic thrombus on pre-operative computed tomography imaging increased the risk of aortic aneurysm development above the infrarenal abdominal aortic aneurysm repair within both the open abdominal aortic aneurysm (hazard ratio 2.04, p = 0.033) and endovascular repair (hazard ratio 3.31, p = 0.004) cohorts. Endovascular repair was independently associated with a higher risk of future aortic aneurysm development after infrarenal abdominal aortic aneurysm repair when compared to open abdominal aortic aneurysm (hazard ratio 2.19, p = 0.025).

CONCLUSIONS

Visceral aortic thrombus present prior to abdominal aortic aneurysm repair and endovascular repair are both associated with an increased risk of future proximal aortic degeneration after infrarenal abdominal aortic aneurysm repair. These factors may predict patients at higher risk of developing proximal aortic aneurysms that may require complex aortic repairs.

Endovascular treatment of para-anastomotic aneurysms after open abdominal aortic surgery

INTRODUCTION

The repair of long-term complications of open abdominal aortic repair such as para-anastomotic aneurysm (PAA) and pseudoaneurysm (PSA) is very challenging. The aim of this study was to assess the outcomes of endovascular repair of PAA/PSA after previous open aortic surgery for aneurismal or occlusive disease.

EVIDENCE ACQUISITION

A systematic review was undertaken; a search was performed (PRISMA) in MEDLINE, CENTRAL, Cochrane databases and key references of all studies of endovascular treatment of PAA/PSA after open aortic surgery.

EVIDENCE SYNTHESIS

Eighteen studies included totally 433 patients (86.3% males) with mean age of 71±2.5 years were identified. Most of the patients were asymptomatic (76%) and diagnosed with PAA (60.5%), while 81.6% had history of open aortic reconstruction for aneurismal disease. The mean diameter of para-anastomotic aneurysms was 59.7 mm (from 23 mm to 110 mm) and the mean duration until their diagnosis was 10±2 years. Standard bifurcated (23.7%), fenestrated (23.4%) and aorto-uni-iliac stent-grafts (16.3%) were mostly used. The technical success rate was 97.8% (391/400) with 1.4% (6/433) 30 day-mortality rate and mean hospital stay of 6±3 days. The mean 1- and 2- year survival rate was 87.8% and 78.8%, respectively. The follow-up ranged from 9 to 43 months, with presenting complications such as endoleak type I (24/378; 6.3%), type II (15/354; 4.3%), type III (3/378;0.8%), migration (4/378; 1%) and limb occlusion (5/310;1.6%). Additionally, 5.7% (19/332) of the patients underwent open conversion, while the total re-intervention rate was 11.4% (39/340; time of reintervention ranged from 7 to 30 months). In cases in which a stent was used for splanchnic vessels (renal artery: 188, superior mesenteric artery: 98, celiac artery: 64), the primary patency rate was 97.4% (341/350).

CONCLUSIONS

Endovascular treatment of PAAs and PSAs after previous open aortic surgery is a feasible and efficient option with high technical success rate, low 30-day mortality and good mid-term outcomes.

Successful endovascular management of endoleak-like phenomenon following open abdominal aortic aneurysm repair

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Endoleaks after open abdominal aortic aneurysm (AAA) repair are a rare.

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Type I endoleak-like phenomenon post-open AAA is also defined as a proximal pseudoaneurysm.

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Type I endoleak-like phenomenon may result in aneurysmal sac rupture into the peritoneal cavity.

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This is the first reported case in the literature of successful management of concomitant types I and potential type II endoleaks post-open AAA repair using an endovascular approach.

Introduction

Endoleaks are a well-known complication after endovascular aortic repair. Type I endoleak-like phenomenon (also defined as a proximal pseudoaneurysm) post-open abdominal aortic aneurysm (AAA) repair is described as an anastomotic leak causing recurrent pressurization of the original aneurysm sac. It is rare but may result in aneurysmal sac rupture into the peritoneal cavity.

Report

A 78-year-old man presented with a progressively enlarged aneurysmal sac due to proximal anastomotic degeneration of the proximal suture line associated with an outflow through a patent large lumbar vessel following a previous emergency open AAA repair. This was successfully treated using a combination coils and ethylene-vinyl alcohol copolymer. An Endoluminal tube stent graft was successfully deployed to seal the aortic anastomotic dehiscence.

Conclusion

Endovascular treatment of an anastomotic dehiscence associated with a large outflow lumbar artery post-open AAA repair is feasible and safe.

Endovascular Solutions to Complications of Open Aortic Repair

Open repair of abdominal aortic aneurysms (AAAs) or occlusive disease can be complicated by pseudoaneurysm formation and aneurysmal dilatation of native vessels. Reports of reoperation for these new lesions have a mortality rate of 5–17% electively, and 24–88% if ruptured. These complications are commonly several years after initial repair, and progression of other comorbidities can further complicate a repeat exploration. The authors reviewed 5 cases of late complications of open aortic bypass surgery treated with endovascular stent grafting as an alternative to reexploration in patients with increased risk for morbidity and mortality. Over a 6-year experience, 5 patients underwent endovascular stent grafting to repair paraanastomotic aneurysms. Patient records were reviewed and clinical cardiac risk evaluation was performed. Follow-up clinic notes and computed tomography (CT) scans were evaluated. Between October 1996 and February 2002, 5 patients underwent 6 endovascular procedures to repair paraanastomotic aneurysms. Mean period between interventions was 16.6 ±6.27 years (range 10–25); mean age at endovascular procedure 74.2 ±6.37 years (range 67–84). Cardiac clinical risk index increased in 80% of patients by Goldman Risk Index and in 40% by the Modified Cardiac Risk Index. On completion angiography, there was complete exclusion of the paraanastomotic aneurysms in all cases (100%). Length of postoperative stay was 1.5 ±0.547 days. Mean estimated blood loss at conclusion of endovascular procedure was 577 ±546.504 cc (range, 60 cc–1,500 cc). Mean follow-up was 24.4 ±24.593 months (range, 5–67 months). On repeat imaging, all stent grafts remain patent without rupture or endoleak. Endovascular stent grafting to repair late complications of open AAA repair is a viable alternative to reexploration in patients with significant comorbidities. These procedures can be performed without violating the previous surgical planes of sites. The operations can be performed under local anesthesia and with reduced hospitalizations. In patients with increased risk factors, endovascular stent grafting is a less morbid alternative to open surgical techniques.

Prevention of perioperative vascular prosthetic infection with a novel triple antimicrobial-bonded arterial graft

OBJECTIVE

Previously, we investigated a locally developed technique of bonding arterial grafts with three antimicrobials to protect against early (within 2 weeks) perioperative bacterial contamination encountered occasionally during aortic graft prosthetic reconstruction. Vascular graft infections are classified by their appearance time (early [<4 months] vs late [>4 months] after graft implantation), degree of incorporation into the surrounding vessel wall, connectivity to the postoperative wound, and extent of graft involvement. In the current phase of testing, we evaluated the ability of our novel triple antimicrobial-bonded graft to prevent infection in the first 8 weeks after implantation.

METHODS

In nine Sinclair miniature pigs, we surgically implanted a 6-mm vascular Dacron patch graft in the infrarenal abdominal aorta. Five pigs received grafts chemically bonded with a 60-mg/mL solution of rifampin, minocycline, and chlorhexidine, and four pigs received unbonded grafts. Before implantation, the five bonded grafts and three of the unbonded grafts were immersed for 15 minutes in a 2-mL solution containing 1-2 × 10⁷ colony-forming units (CFUs)/mL of Staphylococcus aureus (ATCC 29213); the fourth unbonded graft served as a control.

RESULTS

At week 9, all of the grafts were explanted. All S aureus-inoculated bonded grafts (n = 5) showed no bacterial growth. The unbonded, uninoculated graft (n = 1) showed low-level bacterial growth (<1.2 × 10³ CFUs); S cohnii spp urealyticus, but not S aureus, was isolated, which suggested accidental direct perioperative contamination. Two pigs that received S aureus-inoculated, unbonded grafts were euthanized because of severe S aureus infection (<6.56 × 10⁸ CFUs per graft). Results of histopathologic analysis were concordant with the microbiologic findings. Most intergroup differences were observed in the inflammatory infiltrate in the aortic wall at the site of graft implantation. In all pigs that received bonded grafts, Gram staining showed no bacteria.

CONCLUSIONS

Our triple-bonded aortic graft prevented perioperative aortic graft infection for at least 8 weeks in a porcine model. The synergistic antimicrobial activity of this graft was sufficient to prevent and/or eradicate infection during that period. Further studies are needed to assess the graft's ability to combat early-onset vascular graft infection for up to 4 months.

Long-term complications in two patients after aortoaortic bypass for midaortic syndrome

The midaortic syndrome (MAS) refers to descending thoracic and abdominal aortic coarctation, which is rare and most common in the pediatric population. Open surgical repair, often with aortoaortic bypass, remains a highly effective treatment and is traditionally thought to be definitive despite concerns over patient growth postoperatively. This article presents 2 cases of MAS treated with aortoaortic bypass who developed long-term complications, one related to patient growth and the other to graft-enteric fistula. Consideration must be given to patient growth at operation for MAS, and long-term follow-up is necessary to identify other complications.

Imaging and management of complications of open surgical repair of abdominal aortic aneurysms

Open repair is still considered the reference standard for long-term repair of abdominal aortic aneurysms (AAA). In contrast to endovascular aneurysm repair (EVAR), patients with open surgical repair of AAA are not routinely followed up with imaging. Although complications following EVAR are widely recognized and routinely identified on follow-up imaging, complications also do occur following open surgical repair. With frequent use of multi-slice computed tomography (CT) angiography (CTA) in vascular patients, there is now improved recognition of the potential complications following open surgical repair. Many of these complications are increasingly being managed using endovascular techniques. The aim of this review is to illustrate a variety of potential complications that may occur following open surgical repair and to demonstrate their management using both surgical and endovascular techniques.

A complication of open abdominal aortic aneurysm repair closely resembling a type II endoleak

Endoleak is a well-recognized complication of endovascular treatment of abdominal aortic aneurysms. Despite over 40 years of open transabdominal aortic aneurysm surgery, only in the last decade has endoleak as a complication of open surgery been described. Endoleak after conventional open surgery was first described by Chan et al in 2000 and remains a rare complication. We describe the first reported case of type II endoleak (back-bleeding inferior mesenteric artery) after open repair of abdominal aortic aneurysm, and its successful management by endovascular coil embolization.

Minimally invasive application of thrombin in the treatment of pseudoaneurysms following open aortic surgery

BACKGROUND

Anastomotic leaks are uncommon complications following aortic surgery. To avoid the morbidity associated with a second surgical procedure, minimally invasive techniques have become increasingly popular.

PURPOSE

To evaluate the feasibility and safety of thrombin in interventional treatment of postoperative pseudoaneurysms.

MATERIAL AND METHODS

CT-guided percutaneous injection was chosen in four cases. Endovascular access using an occlusion balloon catheter placed in the orifice of the pseudoaneurysm was utilized in one case.

RESULTS

The average volume of all pseudoaneurysms was 178 ± 190 mL with a volume of the patent lumen of 25 ± 28 mL. All aneurysms thrombosed after injection of 600 ± 237 IU of thrombin. During the follow-up period of an average of 10 months all pseudoaneurysms remained occluded.

CONCLUSION

Our series demonstrates the feasibility of thrombin in the treatment of aortic anastomotic pseudoaneurysms. In combination with occlusion balloon catheters, even wide-necked pseudoaneurysms may be treated successfully. However, further investigations are warranted.

Long-term cardiovascular outcome after elective abdominal aortic aneurysm open repair

BACKGROUND

We analyzed the incidence of late cardiovascular events and mortality after elective infra-/juxtarenal abdominal aortic aneurysm open repair (AAA-OR).

METHODS

We included patients who survived AAA-OR in our center in 1988-2006. We registered late cardiac, cerebrovascular, and peripheral vascular events, as well as all-cause and cardiovascular mortality. We calculated patient survival and freedom from cardiovascular events (Kaplan-Meier) and evaluated risk factors (multivariate analysis).

RESULTS

We studied 297 patients: 292 (98.3%) men, aged 67 +/- 7 (44-83) years, 143 (48.1%) bifurcated grafts. In a mean follow-up of 78.7 +/- 52.9 months, we registered 203 cardiovascular events in 123 (41.4%) patients, at a rate of 0.16 cardiovascular events/patient-year. Eleven (3.7%) patients suffered graft-related complications. Freedom from cardiovascular events was 94.2%, 67.2%, 45.7%, and 27.6% at 1, 5, 10, and 15 years, respectively. Survival was 96.6%, 74.7%, 50.7%, and 31.5%, respectively. The main cause of death was cardiovascular disease (n = 54, 18.2%), followed by cancer (n = 43, 14.5%). Only four (1.3%) deaths were graft-related. Coronary artery disease and chronic renal failure were predictive of cardiovascular mortality (p = 0.033 and 0.006).

CONCLUSION

Although long-term survival is similar to that in the general population, successful AAA-OR patients remain at increased risk of cardiovascular events throughout their lifetime. Graft-related complications are rare, confirming the durability of the procedure.

The management of abdominal aortic aneurysms

Abdominal aortic aneurysms cause about 6000 deaths per year in England and Wales, predominantly from rupture. Significant progress has been made in recent years in developing minimally invasive, endovascular methods of treatment. This review evaluates the current management options for abdominal aortic aneurysm.

Fate of iliac arteries following open abdominal aortic aneurysm repair

Iliac artery aneurysms are a frequent finding in patients with abdominal aortic aneurysms. The decision of whether to perform a tubular or bifurcated repair rests on a balance between the natural history of the iliac arteries during the lifetime of the patient versus the risk of symptomatic pelvic ischemia and the increased complexity of a bifurcated repair. The relatively recent increase in the use of cross-sectional imaging, especially in the setting of long-term endograft surveillance, has provided useful data on which to base these clinical decisions. A tube graft repair appears to be safe and durable in patients undergoing open aneurysm repair, when suitable distal aortic anatomy and normal iliac arteries are present. A bifurcated graft should be considered in younger patients with moderate sized iliac aneurysms (<30 mm in diameter), as well as in almost all patients with larger iliac aneurysms.

Uninfected para-anastomotic aneurysms after infrarenal aortic grafting

PURPOSE

This single-institution retrospective review examines the management of uninfected para-anastomotic aneurysms of the abdominal aorta (PAAA), developed after infrarenal grafting.

MATERIALS AND METHODS

From October 1979 to November 2005, 31 PAAA were observed in our Department. Twenty-six uninfected PAAA of degenerative etiology, including 24 false and 2 true aneurysms, were candidates for intervention and retrospectively included in our database for management and outcome evaluation. Six (23%) patients were treated as emergencies. Surgery included tube graft interposition (n = 12), new reconstruction (n = 8), and graft removal with extra-anatomic bypass (n = 3). Endovascular management (n = 3) consisted of free-flow tube endografts.

RESULTS

The mortality rate among the elective and emergency cases was 5% and 66.6%, respectively (p = 0.005). The morbidity rate in elective cases was 57.8%, whereas 75% in emergency cases (p = 0.99). The survival rate during the follow-up was significantly higher for elective cases than for emergency cases.

CONCLUSION

Uninfected PAAA is a late complication of aortic grafting, tends to evolve silently and is difficult to diagnose. The prevalence is underestimated and increases with time since surgery. The mortality rate is higher among patients treated as an emergency than among patients who undergo elective surgery, therefore, elective treatment and aggressive management in the case of pseudoaneurysm are the keys to obtain a good outcome. Endovascular treatment could reduce mortality. Patients who undergo infrarenal aortic grafting require life-long surveillance after surgery.

Endovascular treatment of anastomotic pseudoaneurysms after aorto-iliac surgical reconstruction

PURPOSE

To assess the effectiveness of endovascular treatment of anastomotic pseudoaneurysms (APAs) following aorto-iliac surgical reconstruction.

MATERIALS

We retrospectively evaluated 21 men who, between July 2000 and March 2006, were observed with 30 APAs, 13 to the proximal anastomosis and 17 to the distal anastomosis. The patients had had previous aorto-iliac reconstructive surgery with a bypass due to aneurysm (15/21) or obstructive disease (6/21). The following devices were used: 12 bifurcated endoprostheses, 2 aorto-monoiliac, 4 aortic extenders, 1 stent-graft leg, and 2 covered stents. Follow-up was performed with CT angiography at 1, 3, and 6 months after the procedure and yearly thereafter.

RESULTS

Immediate technical success was 100%. No periprocedural complications occurred. Four patients died during follow-up from causes not related to APA, and 1 (treated for prosthetic-enteric fistula) from sepsis 3 months after the procedure. During a mean follow-up of 19.7 months (range 1-72 months), 2 of 21 occlusions of stent-graft legs occurred 3 and 24 months after the procedure (treated with thrombolysis and percutaneous transluminal angioplasty and femorofemoral bypass, respectively) and 1 type I endoleak. Primary clinical success rate was 81% and secondary clinical success was 91%.

CONCLUSION

Endovascular treatment is a valid alternative to open surgery and can be proposed as the treatment of choice for APAs, especially in patients who are a high surgical risk. Further studies with larger series and longer follow-up are necessary to confirm the long-term effectiveness of this approach.

Aortic Paraprosthetic-colonic Fistulae: A Review of the Literature

BACKGROUND

Aortic graft-colonic fistulae are a rare complication of aortic reconstructive surgery.

METHODS AND FINDINGS

A comprehensive review of this entity was performed based on the available literature from 1950 until 2006. Available reports were analyzed with respect to demographics, prior surgical intervention and its indication, prosthetic material used during the initial intervention, clinical presentation, the time interval in between the initial operation and symptoms, the method of treatment of the aortic graft-colonic fistula and its outcome.

A magnetic device to eliminate endograft migration: theory and experiment

Endograft migration is a recognized problem in endovascular aneurysm repair, which may lead to aneurysm rupture, acute vessel thrombosis, or occlusion. This study presents a novel device to eliminate endograft migration that involves the use of a ferromagnetic stent graft (internal of vessel) and two magnetic rings (external to vessel, at the two necks of the stent). The magnetic rings (proximal and distal on the graft) with sufficient adhesion force were proposed to eliminate migration without overcompression of the aorta. Specifically, the objectives of the study are (1) to design the geometry and magnetic properties of the magnetic ring based on a mathematical model to produce the necessary tangential force to prevent endograft migration and (2) to validate the theoretical model with in vitro experiments. Our experimental results were in agreement with the numerical model, which showed feasibility of the approach to eliminate migration. This magnetic approach to eliminate endograft migration may lay the foundation for improvement of endograft repair of aortic aneurysm.

Sobrevida tardia de pacientes submetidos à correção aberta eletiva de aneurisma de aorta abdominal

CONTEXTO: Os autores fazem uma revisão dos pacientes operados em hospital privado para determinar a causa da mortalidade tardia, a evolução dos demais segmentos da aorta e as complicações relacionadas à prótese. OBJETIVOS: Relatar o seguimento tardio de uma série de 76 casos operados eletivamente para a correção de aneurisma de aorta abdominal, no período de março de 1995 a janeiro de 2007. MÉTODOS: Convocação dos pacientes para uma consulta de retorno e daqueles que não puderam comparecer pessoalmente através de contato telefônico. RESULTADOS: A mortalidade operatória em 30 dias foi de 5,3%. A sobrevida tardia obtida por curva atuarial foi de 95% em 1 ano, 88% em 3 anos e 72% em 8 anos. As doenças cardiovasculares foram a principal causa de mortalidade tardia, seguidas das neoplasias malignas. A dilatação de segmento de aorta proximal à correção cirúrgica ocorreu em 9,7% dos pacientes operados, e as complicações relacionadas à prótese ocorreram em quatro casos (5,3%), sendo uma infecção de prótese, um pseudo-aneurisma proximal, um pseudo-aneurisma em ilíaca e uma oclusão de ramo. CONCLUSÃO: A cirurgia aberta para correção do aneurisma de aorta abdominal apresenta bom resultado em longo prazo, semelhante ao da literatura nacional e internacional, sendo uma boa opção para o paciente que tenha um baixo risco cirúrgico.

Outcome of common iliac arteries after straight aortic tube-graft placement during elective repair of infrarenal abdominal aortic aneurysms

PURPOSE

To determine the relative rates of common iliac artery (CIA) expansion after elective straight aortic tube-graft replacement of infrarenal abdominal aortic aneurysms (AAA).

METHODS

Five participating centers in this 2004 study entered patients they had managed by an aortoaortic tube graft for elective AAA repair. The procedures took place between January 1995 and December 2003. Postoperative computed tomography (CT) scans were obtained for all patients in 2004 to assess changes in CIA diameter. Measurements on preoperative and postoperative CT scans were all made at the same level using the same technique.

RESULTS

Entered in the study were 147 patients (138 men, 9 women) with a mean age of 68 years. Mean follow-up from aortic surgery to verification of CIA diameter on the postoperative CT scan was 4.8 years. Mean preoperative CIA diameter was 13.6 mm vs 15.2 mm postoperatively. No patient developed occlusive iliac artery disease during follow-up. Three patients (2%) required repeat surgery during follow-up for a CIA aneurysm. The 147 patients were divided into three groups based on preoperative CIA diameter shown in CT scan: group A (n = 59, 40.1%), both CIA were of normal diameter; group B (n = 53, 36.1%), ectasia (diameter between 12 and 18 mm) of at least one CIA; group C (n = 35, 23.8%), an aneurysm (diameter >18 mm) of at least one CIA. CIA diameter increased by a mean of 1 mm (9.4%) over 5.5 years in group A vs 1.7 mm (12.1%) over 4.3 years in group B and 2.3 mm (12.7%) over 4.2 years in group C. The three patients who required repeat surgery for a CIA aneurysm during follow-up were all in group C. Four variables were associated with aneurysmal change in CIA: initial CIA diameter, celiac aorta diameter on the preoperative CT scan, a coexisting aneurysm site, and the follow-up duration.

CONCLUSIONS

Tube-graft placement during AAA surgery is justified even for moderate CIA dilatation (<18 mm). CIA aneurysms with a preoperative diameter > or =25 mm enlarge more rapidly and warrant insertion of a bifurcated graft during the same surgical session as AAA repair. The evolutive potential of CIA between 18 mm and 25 mm in diameter justifies a bifurcated graft when the celiac aorta diameter is >25 mm or the patient's life expectancy is > or =8 years.

Aortic necks of ruptured abdominal aneurysms dilate more than asymptomatic aneurysms after endovascular repair

BACKGROUND

Endovascular repair of abdominal aortic aneurysm (AAA) is increasingly used. We evaluated if a difference exists in the rate of change of the aortic neck diameter between non-ruptured and ruptured AAAs after endovascular aneurysm repair (EVAR).

METHODS

Details of patients undergoing elective (group I) and emergency (group II) EVAR using Talent stents between October 1999 and September 2005 were reviewed. Top neck diameters were prospectively recorded on the hospital database from computed tomography scans preoperatively and at 1, 3, 12, and 24 months postoperatively. The aortic neck diameter rate of change was calculated for each group.

RESULTS

Endovascular repair was performed on 110 elective and 41 emergency patients, of which 100 (80 male) elective and 29 (26 male) emergency patients were included in this analysis. Mean age was similar in each group. Stents were oversized by 20.9% +/- 13.6% in group I and by 24.7% +/- 16.3% in group II (P = .37). The preoperative mean proximal aortic neck was larger in group II (25.0 +/- 3.3 mm vs 23.5 +/- 2.8 mm; P = .029). The growth rate of the top neck diameter was significantly greater at 12 months (1.48 +/- 2.4 mm/year vs 3.89 +/- 6.24 mm/year; P = .04) and 24 months (.99 +/- 1.1 mm/year vs 2.61 +/- 3.3 mm/year; P = .04) in group II than in group I. A decreasing sac size was found in 68.2% of patients whose neck dilated. The complication rate was similar in each group.

CONCLUSION

Aneurysm necks in patients with ruptured aneurysms are larger and dilate at a greater rate than those with nonruptured aneurysms. The accelerated rate of expansion in some patients must be borne in mind during follow-up and in secondary endovascular interventions and conversion to open surgery.

Late reintervention for aortic graft-related events and new aortoiliac disease after open abdominal aortic aneurysm repair in an Australian population

OBJECTIVE

To examine late reintervention rates for aortic graft-related events and new aortoiliac disease after open abdominal aortic aneurysm (AAA) repair in an Australian population.

METHODS

Interrogation of a prospective computerized database identified 1256 consecutive patients (1058 men, 198 women; median age, 70 years; range, 40 to 97 years) who survived open repair of nonruptured (n = 957, group I) and ruptured (n = 299, group II) infrarenal AAA in a single institution between January 1, 1982 and December 31, 2003. Median (range) follow-up was 41 (1 to 261) months for group I and 30 (1 to 243) months for group II.

RESULTS

In group I, 33 patients (3.4%) underwent 38 late reinterventions: 20 patients (2.1%) for aortic graft-related events at a median (range) interval of 36 (1 to 94) months after the index AAA repair, with a 30-day mortality rate of 15%; and 13 patients (1.4%) for new aortoiliac disease at a median (range) interval of 33 (3 to 207) months, with 30-day mortality of 8%. In group II, 15 patients (5%) underwent 16 late reinterventions: 10 patients (3.3%) for aortic graft-related events at a median (range) interval of 5 (2 to 112) months, with a 30-day mortality of 10%; and five patients (1.7%) for new aortoiliac disease at a median (range) interval of 67 (39-105) months, with a 30-day mortality of 40%. There was no significant difference in the late reintervention rate between the groups: group I, 33 (3.4%) of 957 vs group II, 15 (5%) of 299 (P = .23). For all patients, the estimated survival at 1, 3, 5 and 10-years was 90%, 79.4%, 66.4%, and 31.6%, respectively; estimated survival free from reintervention at 1, 3, 5 and 10-years was 98.7%, 97.1%, 95.1%, and 91.9%, respectively.

CONCLUSIONS

These data demonstrate, for the first time, that open AAA repair has excellent long-term durability in an Australian population and the results compare favorably with previous reports from North America and Europe. These data represent an important benchmark for comparison of the results of endovascular AAA repair in this patient population.

Abdominal wall hernias after open abdominal aortic aneurysm repair: prospective radiographic detection and clinical implications

The purpose of this study was to evaluate the prevalence of radiographically detected abdominal wall defects (AWD) after open abdominal aortic aneurysm (AAA) repair and to correlate it with prospectively gathered clinical information. Fine collimation, high-resolution, serial follow-up computed tomography (CT) scans for 99 patients in the control group of the Guidant Ancure device trial were reviewed. CT scans were obtained at 12, 24, 36, 48, and 60 months. AWDs, defined as discontinuity of the fascial layer with protrusion of abdominal contents, were identified. Clinical information regarding AWDs was retrieved from the study registry. The prevalence of AWD exceeds 20% and plateaus at 24 months. Eight patients (8%) had clinical evidence of ventral incisional hernias. One patient underwent repair, but no other patient developed hernia incarceration or intestinal obstruction or required additional procedures related to the AWD. AWDs are radiographic findings occurring frequently after open AAA repair. Radiographic evaluation is more sensitive than clinical observation for detection of ventral hernias. Clinical events and reinterventions related to these radiographic abnormalities are rare.

Thoracovisceral segment aneurysm repair after previous infrarenal abdominal aortic aneurysm surgery

OBJECTIVE

Repair of thoracovisceral aortic aneurysms (TVAA) after previous open repair of an infrarenal abdominal aortic aneurysm (AAA) poses significant challenges. We sought to better characterize such recurrent aneurysms and to evaluate their operative outcome.

METHODS

We reviewed the records and radiographs of 49 patients who underwent repair of TVAAs between 1988 and 2002 after previous repair of an AAA. Visceral artery reconstructions were completed with combinations of beveled anastomoses, inclusion patches, and side arm grafts. In 14 patients visceral endarterectomy was required to treat associated occlusive disease. Sixteen patients had cerebrospinal fluid drainage, and 10 patients had distal perfusion during cross-clamping.

RESULTS

Patient mean age was 72 years, and 80% were men. Fifty-one percent of patients had symptomatic disease, and average TVAA diameter was 6.2 cm. Mean time between AAA and TVAA repair was 77 months. Twenty-six percent of aneurysms were restricted to the lower visceral aortic segment, 35% extended to the diaphragm, another 35% extended to the distal or middle thoracic aorta, and 4% involved the entire remaining visceral and thoracic aorta. The 30-day operative mortality rate was 4.1% in patients with nonruptured aneurysms and 50% in patients with ruptured aneurysms, for an overall mortality rate of 8.2%. Fifteen patients (30.6%) had major morbidity, including paresis in two patients and dialysis-dependent renal failure in five patients. At late follow-up, three patients required further aortic operations to treat additional aneurysms, and four patients had fatal aortic ruptures. Two-year and 5-year cumulative survival rates were 61% (+/-7.5%) and 37% (+/-7.8%), respectively. At univariate analysis, operative blood loss was the sole significant predictor of major morbidity (P <.023), and rupture (P <.030, P <.0001) and aneurysm extent (P <.0007, P <.0001) correlated with both operative death and long-term survival. Only aneurysm extent (P <.010, relative risk 37.3) remained a significant predictor of long-term survival at multivariate analysis.

CONCLUSION

Elective repair of TVAAs after previous AAA repair can be performed with an acceptable level of operative mortality, though with considerable operative morbidity. Limited long-term survival mandates careful patient selection, and the high mortality associated with ruptured TVAA underscores the need for post-AAA surveillance.

The Gore Excluder US multi-center trial: analysis of adverse events at 2 years

Although open surgical repair of abdominal aortic aneurysms remains the standard of care, endovascular repair is becoming an attractive alternative as more long-term outcome data become available to show its safety and efficacy. The authors review data on the 2-year outcome of the pivotal US multicenter, prospective Gore Excluder Trial. Patients treated with the Excluder endograft (W.L. Gore, Flaggstaff, AZ) had less blood loss (310 +/- 19 v 1,590 +/- 124 mL; P <.0001), required fewer homologous transfusions (6% v 32%; P <.0001), and had faster inpatient recovery (2.0 +/- 0.1 v 9.8 +/- 1.4 days; P <.0001) compared with those treated with open repair. Early major adverse events were reduced significantly in the patients treated with the endograft (14% v 57% in control; P <.0001), and this persisted at 2 years. There was no difference in overall survival rate (P =.13). There were no deployment failures, early conversions, or aneurysm ruptures. At the 2-year time-point, trunk migration occurred in 1%, limb migration in 1%, limb narrowing in 1%, endoleak in 20%, and aneurysm growth in 14%. There was a 7% annual reintervention rate in the endograft group in the first 2 years. The Excluder endograft is a safe and effective treatment compared with open surgical repair for infrarenal abdominal aortic aneurysms with appropriate anatomy.

Guidelines for the treatment of abdominal aortic aneurysms. Report of a subcommittee of the Joint Council of the American Association for Vascular Surgery and Society for Vascular Surgery

Decision-making in regard to elective repair of abdominal aortic aneurysms (AAA) requires careful assessment of factors that influence rupture risk, operative mortality, and life expectancy. Individualized consideration of these factors in each patient is essential, and the role of patient preference is of increasing importance. It is not possible or appropriate to recommend a single threshold diameter for intervention which can be generalized to all patients. Based upon the best available current evidence, 5.5 cm is the best threshold for repair in an "average" patient. However, subsets of younger, good-risk patients or aneurysms at higher rupture risk may be identified in whom repair at smaller sizes is justified. Conversely, delay in repair until larger diameter may be best for older, higher-risk patients, especially if endovascular repair is not possible. Intervention at diameter <5.5 cm appears indicated in women with AAA. If a patient has suitable anatomy, endovascular repair may be considered, and it is most advantageous for older, higher-risk patients or patients with a hostile abdomen or other technical factors that may complicate standard open repair. With endovascular repair, perioperative morbidity and recovery time are clearly reduced; however, there is a higher reintervention rate, increased surveillance burden, and a small but ongoing risk of AAA rupture. There is no justification at present for different indications for endovascular repair, such as earlier treatment of smaller AAA. Until long-term outcome of endoluminal repair is better defined and results of randomized trials available, the choice between endovascular and open repair will continue to rely heavily on patient preference.

Conformational changes associated with proximal seal zone failure in abdominal aortic endografts

OBJECTIVE

Endovascular aneurysm repair (EVAR) has become a popular treatment for abdominal aortic aneurysm (AAA). This study examines conformational changes in the infrarenal aortas of patients in whom proximal seal zone failures (PSF) developed after EVAR.

METHODS

All 189 patients with aortic endograft underwent routine post-EVAR computed tomographic scan surveillance. Patients identified with proximal type I endoleaks, type III endoleaks, or proximal component separation without demonstrable endoleak underwent three-dimensional reconstruction of the computed tomographic scans from which measurements of the migration, length, volume, and angulation of the infrarenal aorta were made.

RESULTS

Five patients (3%) had PSF develop, four of whom had aortic extender cuffs. Although changes in the AAA volume and aortic neck angle were slight or variable, the mean AAA length increased 34 mm and the mean aortic body angulation increased 17 degrees (P =.03 and.01, respectively). Lengthening and migration caused proximal component separation in four patients, with concomitant migration in two patients. Two patients underwent endovascular repair, two patients needed explantation of the endograft, and one patient awaits endovascular repair. Proximal component separation and type III endoleak recurred in one patient and were repaired with a custom-fitted graft.

CONCLUSION

PSF of aortic endografts is associated with proximal angulation and lengthening of the infrarenal aorta. These findings reinforce the importance of proper initial deployment to minimize the need for aortic extender cuffs, which pose a risk of late endoleak development.

Endovascular repair reduces early and late morbidity compared to open surgery for abdominal aortic aneurysm

PURPOSE

To compare systemic complications between standard surgery and endovascular repair of abdominal aortic aneurysms (AAA) for both primary and late secondary procedures.

METHODS

At a single center between July 1993 and May 2000, 297 patients (255 men; mean age 73.4 +/- 8.1 years, range 50-93) were treated with open surgical repair; beginning in 1996, 200 (166 men; mean age 73.6 +/- 8.0 years, range 45-96) patients were treated with the AneuRx stent-graft. In a comparison of the cohorts, which were similar in terms of age, gender, and aneurysm diameter, the main outcomes were early major systemic morbidity following the primary procedure to treat the aneurysm and late (>30 days) organ system morbidity for any secondary procedures.

RESULTS

Mean length of follow-up for open patients was 20.1 +/- 17.1 months (range 1-150) compared to 12.4 +/- 9.6 months (range 1-60) after endovascular repair (p<0.05). There were 36 (12.1%) systemic complications after the primary open surgery and 15 (7.5%) after endovascular repair (p=NS). There were 43 (14.5%) combined primary and secondary morbidities in the open surgery group versus 15 (7.5%) for patients undergoing endovascular repair (p<0.01). The need for invasive procedures to treat these primary and secondary systemic complications was 4 times greater in the open group (17, 5.7%) than in endograft patients (3, 1.5%) (p<0.05). After secondary procedures (32 in the open group and 30 in the endovascular patients) for graft-related complications, there were 7 (21.9%) adverse events in the open group versus none (0%) for endograft patients (p<0.01). Hospital lengths of stay following both primary and secondary procedures were lower for the endograft patients (p<0.01 and p<0.001, respectively).

CONCLUSIONS

Endovascular stent-graft repair compared to open surgery has reduced the early and late morbidity by half. Complications that require invasive or secondary surgical procedures and hospitalization are reduced with endovascular repair.

Infrarenal rupture of an abdominal aortic aneurysm, previously repaired using an endoaneurysmorrhaphy technique

Unusual as well as well-known complications can occur after aortic reconstruction. In an effort to heighten awareness of these possibilities, a case is presented of a 71-year-old male who was brought to the emergency department with severe back pain of 2 days duration and hypotension. He had undergone repair of an infrarenal abdominal aortic aneurysm 6 years earlier. An emergency computed tomography scan demonstrated a 10-cm abdominal aortic aneurysm extending from just above the celiac axis, through the aortic bifurcation, with retroperitoneal and intraperitoneal hematoma. He was found at operation to have extension of his aneurysmal disease proximally, with complete separation of the proximal suture line, and rupture of the distal aortic wall. Since the aneurysm had been closed around the graft at the time of the original operation, his aneurysm had essentially been restored, and the diseased wall was again exposed to the tensile stresses from the pulsatile column of blood. Emergency repair was successful, despite postoperative complications including myocardial infarction, and later rupture of an iliac artery aneurysm. Patients presenting with signs and symptoms consistent with a ruptured abdominal aortic aneurysm after previous repair should be addressed aggressively with computed tomography if it is immediately available and the diagnosis is in doubt. The patient should then undergo an immediate operation. Such recurrence, although rare, must always be considered a possibility. Similar scenarios may be encountered secondary to endoleaks occurring after endoluminal aortic repairs.