Open Versus Endovascular Abdominal Aortic Aneurysm Repair in VA Hospitals

Follow-up compliance in patients undergoing abdominal aortic aneurysm repair at Veterans Affairs hospitals

OBJECTIVE

The Society for Vascular Surgery guidelines recommend annual imaging surveillance following endovascular aneurysm repair (EVAR) and every 5 years following open surgical repairs (OSR) of abdominal aortic aneurysms (AAAs). Adherence to these guidelines is low outside of clinical trials, and compliance at Veterans Affairs (VA) hospitals is not yet well-established. We examined imaging follow-up compliance and mortality rates after AAA repair at VA hospitals.

METHODS

We queried the VA Surgical Quality Improvement Program database for elective infrarenal AAA repairs, EVAR and OSR, then merged in follow-up imaging and mortality information. Mortality rate over time was derived using Kaplan-Meier estimation. Generalized estimating equation with a logit link and a sandwich standard error estimate was performed to compare the probability of having annual follow-up imaging over time between procedure types and to identify variables associated with follow-up imaging for EVAR patients.

RESULTS

Our analysis included 11,668 patients who underwent EVAR and 4507 patients who underwent OSR at VA hospitals between the years 2000 and 2019. The 30-day mortality rate for EVAR and OSR was 0.37% and 0.82%, respectively. OSR was associated with lower long-term mortality after adjusting age, sex, American Society of Anesthesiologists classification and preoperative renal failure with an adjusted hazard ratio of 0.88 (95% confidence interval, 0.84-0.92; P < .01). Of surviving patients, the follow-up imaging rate was 69.1% by 1 year post-EVAR. The follow-up rate after 5 years was 45.6% post-EVAR compared with 63.6% post-OSR of surviving patients. A history of smoking or drinking, baseline hypertension, and known cardiac disease were independently associated with poor follow-up after EVAR.

CONCLUSIONS

Patients undergoing elective open AAA repair in the VA hospital system had lower long-term mortality compared with patients who underwent endovascular repair. Compliance with post-EVAR imaging is low. Patient factors associated with poor post-EVAR imaging surveillance were smoking within the last year, excess alcohol consumption, and cardiac risk factors including hypertension, prior myocardial infarction, and congestive heart failure.

External iliac artery extension causes greater aneurysm sac regression than the bell-bottom technique or iliac branch endoprosthesis for repair of concomitant infrarenal aortic and iliac artery aneurysm

OBJECTIVE

Aneurysmal extension of abdominal aortic aneurysms (AAAs) to the common iliac artery (CIA) presents a technical challenge to successful endovascular abdominal aortic aneurysm repair (EVAR). In the present study, we compared sac shrinkage and perioperative outcomes after the bell-bottom technique (BBT), internal iliac artery embolization and external iliac artery extension (EIE), and iliac branch endoprosthesis (IBE).

METHODS

Using the Vascular Quality Initiative database, a retrospective analysis was conducted for patients who had undergone EVAR from 2013 to 2019. The demographic, anatomic, and perioperative data were analyzed. All patients with a proximal aortic neck length <10 mm and aortic graft diameter >32 mm were excluded from the analysis. The patients were subdivided into four groups according to the distal limb strategy: group 1, control group with a bilateral common iliac artery limb <20 mm; group 2, BBT with either a unilateral or bilateral limb >20 mm; group 3, EIE technique; and group 4, IBE. The primary endpoint was the maximal change in the aortic diameter during follow-up. The secondary endpoints included postoperative complications and the rate of endoleak.

RESULTS

The records for 14,455 patients who had undergone EVAR were queried and 5788 met the anatomic criteria. The average age was 73 years, and 86.3% were men. The maximal change in the aortic diameter in the control, BBT, IBE, and EIE groups was -7.2 mm, -6.1 mm, -4.6 mm, and -6.8 mm, respectively (P = .06). The differences were not statistically significant on univariate analysis at an average follow-up of 405 days. However, on multivariable analysis (P = .01), compared with the control group, the BBT and IBE groups were 18.4% (odds ratio [OR], 0.816; 95% confidence interval [CI], 0.68-0.98) and 48.0% (OR, 0.52; 95% CI, 0.33-0.82) less likely to experience aneurysmal shrinkage, respectively. In contrast, the EIE group showed no significant difference in shrinkage compared with that in the control group. Multivariable analysis of the groups also revealed that compared directly with the BBT group, the EIE group was 69.5% more likely to have experienced shrinkage in the aortic aneurysmal diameter (OR, 1.70; 95% CI, 1.05-2.75). The BBT and IBE groups had a significantly higher rate of type II endoleaks (17.63% and 16.95%, respectively; P = .03). The EIE group had a higher rate of type Ib endoleaks (1.9%) compared with the BBT (1.1%), IBE (1.7%), and control (0.3%) groups (P = .01). No differences were found between the groups in terms of postoperative myocardial infarction (P = .47) or respiratory (P = .61) or intestinal (P = .71) complications. However, the rates of limb complications and reoperation were higher in the EIE group.

CONCLUSIONS

The present study revealed that the EIE technique was more likely to demonstrate shrinkage in the aortic aneurysmal diameter than were the BBT and IBE groups compared with the control group on multivariable analysis. The EIE technique was also more likely to result in aneurysmal sac shrinkage than was the BBT group, albeit with greater rates of limb-related complications.

Abdominal Aortic Aneurysm: A Case Report and Literature Review

INTRODUCTION

Abdominal aortic aneurysms (AAA) more commonly affect men than women and are estimated to affect 4% to 8% of men older that age 60 years. Mortality because of a ruptured AAA is high, but elective repair is an effective and relatively safe intervention.

CASE PRESENTATION

A 79-year-old man came to the Emergency Department because of worsening back pain. Workup revealed a previously unknown, 10-cm aneurysm that had ruptured. Unfortunately, the patient died during emergency surgery.

DISCUSSION

A literature review of proper screening, referral timeframe, the most common surgical techniques, potential complications, and postoperative surveillance was conducted. Early detection, referral to vascular surgery, and possible open or endovascular repair are key to limiting the morbidity and mortality associated with AAA.

Endovascular Repair of Aortoiliac or Common Iliac Artery Aneurysm Using the Lifetech Iliac Bifurcation Stent Graft System: A Prospective Multicenter Clinical Study

BACKGROUND

Sacrifice of the internal iliac artery (IIA) may result in ischemic manifestations after aortoiliac aneurysm (AIA) or common iliac artery aneurysm (CIAA) endovascular repair. This study sought to evaluate the safety and efficacy of a new Iliac Bifurcation Stent Graft (IBSG; Lifetech Scientific, Shenzhen, China) system for revascularization of the IIA.

METHODS

Patients who underwent implantation of the IBSG at 8 centers in China from September 2015 to June 2018 were enrolled. Clinical and computed tomography angiography follow-up assessments were conducted at 30 and 180 days postoperatively. The primary end point was the IIA patency rate of the IBSG device at 180 days postoperatively. Secondary end points comprised the postoperative technical success rate and clinical success rate at 30 and 180 days. Descriptive statistics and the Clopper-Pearson exact method were used to analyze the data.

RESULTS

Seventy-three patients (mean age, 69.6 years; 91.8% men) were eligible for this trial, and 59 patients were eligible for primary effectiveness end-point analysis. AIA was present in 55 patients (75.34%) and CIAA in 18 patients (24.66%). The iliac artery aneurysms were unilateral in 69 patients (94.52%) and bilateral in 4 patients (5.48%). Overall technical success was 89.04% (65 of 73 patients). IIA patency at 180 days was 96.61% (57 of 59 patients). Sexual dysfunction occurred in 1 patient (1.69%), and 2 patients (3.39%) experienced buttock claudication. There was no mortality, type III endoleak, stent migration, kinking, or fracture during the procedure and follow-up.

CONCLUSIONS

The IBSG implantation system is a safe and effective technique for IIA preservation during AIA or CIAA endovascular repair. The high technical success rate, IIA patency rate, and low complication rate are promising. Follow-up will be continued for 5 years to confirm the durability of the device.

Unplanned 30-day readmissions after endovascular aneurysm repair: An analysis using the Nationwide Readmissions Database

BACKGROUND

Endovascular aneurysm repair (EVAR) is the preferred method for addressing abdominal aortic aneurysms (AAAs), with proven reduction in perioperative morbidity and mortality. There are, however limited data examining the readmissions after EVAR that are associated with increased patient morbidity and cost. As EVAR use continues its dominance in the management of AAAs, it becomes imperative to identify and mitigate risk factors associated with unplanned hospital readmissions.

METHODS

The Nationwide Readmissions Database (NRD) was queried for all 30-day readmissions after an index EVAR procedure from 2012 to 2014. Preoperative patient demographics, hospital characteristics, readmission diagnosis, and costs were compared between those who were and were not readmitted within 30 days of the index operation. Multivariable logistic regression was used to identify potential risk factors associated with unplanned readmissions within 30 days.

RESULTS

We identified 120,646 patients who underwent an EVAR from 2012 to 2014 in the United States. The overall unplanned readmission rate during this period was 11.6% (n = 14,073) within 30 days of the index EVAR procedure. The readmission rate was the highest in 2012, with a rate of 12.3% (P = .02). Multivariate regression analysis showed that EVAR readmissions were significantly higher in patients who were of younger age (18 to 49 years) compared with other age groups (odds ratio [OR], 1.9-2.17; P < .001), female sex (OR, 1.367; P < .001), had Medicare (OR, 1.39) or Medicaid (OR, 1.25) insurance, or a combination of these. Underlying patient comorbidities significantly associated with readmissions included congestive heart failure (OR, 2.4), peripheral vascular disease (OR, 1.1), chronic pulmonary disease (OR, 1.2), cancer with no metastasis (OR, 1.5), metastatic cancer (OR, 2.2), renal failure (OR, 1.8), and diabetes (OR, 1.5).

CONCLUSIONS

The trend in 30-day readmission rates after EVAR has decreased slightly since 2012, but overall rates are at 11.6%, which is not insubstantial. Patient factors strongly associated with hospital readmission were younger age and patient comorbidities, including congestive heart failure, concurrent cancer diagnosis, renal failure, and diabetes.

Meta-analysis of long-term survival after elective endovascular or open repair of abdominal aortic aneurysm

BACKGROUND

Endovascular aneurysm repair (EVAR) has become the preferred strategy for elective repair of abdominal aortic aneurysm (AAA) for many patients. However, the superiority of the endovascular procedure has recently been challenged by reports of impaired long-term survival in patients who underwent EVAR. A systematic review of long-term survival following AAA repair was therefore undertaken.

METHODS

A systematic review was performed according to PRISMA guidelines. Articles reporting short- and/or long-term mortality of EVAR and open surgical repair (OSR) of AAA were identified. Pooled overall survival estimates (hazard ratios (HRs) with corresponding 95 per cent c.i. for EVAR versus OSR) were calculated using a random-effects model. Possible confounding owing to age differences between patients receiving EVAR or OSR was addressed by estimating relative survival.

RESULTS

Some 53 studies were identified. The 30-day mortality rate was lower for EVAR compared with OSR: 1·16 (95 per cent c.i. 0·92 to 1·39) versus 3·27 (2·71 to 3·83) per cent. Long-term survival rates were similar for EVAR versus OSR (HRs 1·01, 1·00 and 0·98 for 3, 5 and 10 years respectively; P = 0·721, P = 0·912 and P = 0·777). Correction of age inequality by means of relative survival analysis showed equal long-term survival: 0·94, 0·91 and 0·76 at 3, 5 and 10 years for EVAR, and 0·96, 0·91 and 0·76 respectively for OSR.

CONCLUSION

Long-term overall survival rates were similar for EVAR and OSR. Available data do not allow extension beyond the 10-year survival window or analysis of specific subgroups.

Open surgery and endovascular repair for mycotic aortic aneurysms: Benefits beyond survival

OBJECTIVE

Endovascular techniques have been increasingly used to treat mycotic aortic aneurysms. However, apart from survival, the potential benefits of open surgery and endovascular repair for mycotic aortic aneurysms are poorly understood. The aim of this study was to evaluate the short- and mid-term outcomes after open surgery versus endovascular repair for mycotic aortic aneurysms.

METHODS

All patients treated for mycotic aortic aneurysms at Peking University People's Hospital between 2001 and 2017 were identified. Survival was analyzed using Kaplan-Meier analysis and log-rank tests. The reoperation rate was analyzed using a competing-risk analysis.

RESULTS

Forty-three patients were identified. The mean follow-up time was 41 months (median, 29; range, 1-135 months). The 30-day mortality in the open surgery group was 8.7% (2/23) versus 5% (1/20) in the endovascular repair group (P = .999). The overall survival for open surgery and endovascular repair was 78% versus 75%, respectively, at 1 year, and 69% versus 41% (P = .210), respectively, at 5 years. But during the follow-up, the open surgery group demonstrated multiple benefits, including a shorter length of hospital stay (26.80 ± 14.1 days vs 42.73 ± 21.22 days, P = .026), fewer readmissions (mean 0.61 vs 1.30, P = .037), and lower infection-related reoperations (P = .018) than endovascular repair at 3 years. Subgroup analysis revealed better survival for open surgery in patients with a periaortic mass less than 20 mm (P = .03).

CONCLUSIONS

There were no significant differences between endovascular repair and open surgery in survival. However, in the mid-term, the potential benefits of open surgery are favorable compared with endovascular repair, including lower infection-related reoperation rates and reduced medical burden.

Comparative study of clinical outcome of endovascular aortic aneurysms repair in large diameter aortic necks (>31 mm) versus smaller necks

BACKGROUND

This study compares short-term (30 days) and intermediate term (3 years) clinical outcomes in patients with large (≥31 mm) versus small aortic neck diameters (≤28 and ≤31 mm).

METHODS

Prospectively collected data from 741 patients who underwent endovascular aortic aneurysm repair were analyzed. Some surgeons have reported the threshold for a large aortic neck for endovascular aortic aneurysm repair to be 28 mm, whereas for others it is 31 mm. Therefore, we classified aortic neck diameter into less than or equal to 28 versus greater than 28 mm; and less than or equal to 31 versus greater than 31 mm. Logistic regression and Kaplan-Meier analyses were used to compare outcomes.

RESULTS

There were 688 patients who had a defined aortic neck diameter: 592 with less than or equal to 28 mm, 96 with greater than 28 mm, 655 with less than or equal to 31 mm, and 33 with greater than 31 mm. The mean follow-up was 25.2 months for less than or equal to 31 mm versus 31.8 months for greater than 31 mm. Clinical characteristics were similar in all groups, except that there were more patients outside the instructions for use in the greater than 31 mm versus less than or equal to 31 mm group (94% vs 44%; P < .0001). There was a significant increase in early type I endoleak for patients with an aortic neck diameter of greater than 31 versus less than or equal to 31 mm (9 [27%] vs 74 [11%]; P = .01); late type I endoleaks (4 [14%] vs 18 [3%]; P = .01); sac expansion (5 [17%] vs 28 [5%]; P = .01); late intervention (5 [17%] vs 23 [4%]; P = .01); and death (9 [31%] vs 48 [8%]; P < .0001). There were no differences in outcomes between the patients with greater than 28 mm aortic neck diameters and the less than or equal to 28 mm diameters. Freedom from late type I endoleak at 1, 2, and 3 years were 96%, 88%, and 88% for patients with a neck diameter of greater than 31 mm versus 97%, 97%, and 97% for a diameter less than or equal to 31 mm (P = .19). The rate of freedom from sac expansion for patients with a diameter greater than 31 mm was 88%, 81%, and 81% at 1, 2, and 3 years versus 99%, 97%, and 92% for a diameter less than or equal to 31 mm (P = .02). Freedom from late intervention for 1, 2, and 3 years for patients with a diameter greater than 31 mm were 91%, 91%, and 91% versus 99%, 97%, and 96% for those with a diameter less than or equal to 31 mm. Survival rates at 1, 2, and 3 years for a diameter greater than 31 mm were 83%, 74%, and 68% versus 96%, 92%, and 90% for a diameter less than or equal to 31 mm (P < .001). Multivariate logistic regression analysis showed that patients with a diameter greater than 31 mm had an odds ratio of 6.1 (95% confidence interval [CI], 2.2-16.8) for mortality, 4.7 (95% CI, 1.4-15.5) for sac expansion, and 4.9 (95% CI, 1.4-17.4) for late type I endoleak.

CONCLUSIONS

Patients with large aortic neck diameters (>31 mm) had higher rates of early and late type I endoleak, sac expansion, late intervention, and mortality.

Laparoscopic surgery for elective abdominal aortic aneurysm repair

BACKGROUND

Abdominal aortic aneurysm (AAA) is an abnormal dilatation of the infradiaphragmatic aorta that is equal to or greater than 30 mm or a local dilatation of equal to or greater than 50% compared to the expected normal diameter of the artery. AAAs rarely occur in individuals under 50 years of age, but thereafter the prevalence dramatically increases with age, with men at a six-fold greater risk of developing an AAA than women. Prevalence of AAA has been reported to range from 1.3% in women aged 65 to 80 years to between 4% and 7.7% in men aged 65 to 80 years.There is evidence that the risk of rupture increases as the aneurysm diameter increases from 50 mm to 60 mm. People with AAAs over 55 mm in diameter are therefore generally referred for consideration of repair, as the risk of rupture exceeds the risk of repair. The traditional treatment for AAA is open surgical repair (OSR) which involves a large abdominal incision and is associated with a significant risk of complications. Two less invasive procedures have recently become more widely used: endovascular aneurysm repair (EVAR) and laparoscopic repair. EVAR is carried out through sheaths inserted in the femoral artery in the groin: thereafter, a stent graft is placed within the aneurysm sac under radiological image guidance and anchored in place to form a new channel for blood flow. Laparoscopic repair involves the use of a laparoscope which is inserted through small cuts in the abdomen and the synthetic graft is sewn in place to replace the weakened area of the aorta. Laparoscopic AAA repair falls into two categories: hand-assisted laparoscopic surgery (HALS), where an incision is made to allow the surgeon's hand to assist in the repair; and total laparoscopic surgery (TLS). Both EVAR and laparoscopic repair are favourable over OSR as they are minimally invasive, less painful, associated with fewer complications and lower mortality rate and have a shorter duration of hospital stay.Current evidence suggests that elective laparoscopic AAA repair has a favourable safety profile comparable with that of EVAR, with low conversion rates as well as similar mortality and morbidity rates. As a result, it has been suggested that elective laparoscopic AAA repair may have a role in treating those patients for whom EVAR is unsuitable.

OBJECTIVES

To assess the effects of laparoscopic surgery for elective abdominal aortic aneurysm repair.The primary objective of this review was to assess the perioperative mortality and operative time of laparoscopic (total and hand-assisted) surgical repair of abdominal aortic aneurysms (AAA) compared to traditional open surgical repair or EVAR. The secondary objective was to assess complication rates, all-cause mortality (> 30 days), hospital and intensive care unit (ICU) length of stay, conversion and re-intervention rates, and quality of life associated with laparoscopic (total and hand-assisted) surgical repair compared to traditional open surgical repair or EVAR.

SEARCH METHODS

The Cochrane Vascular Information Specialist (CIS) searched the Specialised Register (last searched August 2016) and CENTRAL (2016, Issue 7). In addition the CIS searched trials registries for details of ongoing or unpublished studies. We searched the reference lists of relevant articles retrieved by electronic searches for additional citations.

SELECTION CRITERIA

Randomised controlled trials and controlled clinical trials in which patients with an AAA underwent elective laparoscopic repair (total laparoscopic repair or hand-assisted laparoscopic repair) compared with either open surgical repair or EVAR.

DATA COLLECTION AND ANALYSIS

Studies identified for potential inclusion were independently assessed for inclusion by at least two review authors.

MAIN RESULTS

One randomised controlled trial with a total of 100 male participants was included in the review. The trial compared hand-assisted laparoscopic repair with EVAR and provided results for in-hospital mortality, operative time, length of hospital stay and lower limb ischaemia. The included study did not report on the other pre-planned outcomes of this review. No in-hospital deaths occurred in the study. Hand-associated laparoscopic repair was associated with a longer operative time (MD 53.00 minutes, 95% CI 36.49 to 69.51) than EVAR. The incidence of lower limb ischaemia was similar between the two treatment groups (risk ratio (RR) 0.50, 95% confidence interval (CI) 0.05 to 5.34). The mean length of hospital stay was 4.2 days and 3.4 days in the hand-assisted laparoscopic repair and EVAR groups respectively but standard deviations were not reported and therefore it was not possible to independently test the statistical significance of this result. The quality of evidence was downgraded for imprecision due to the inclusion of one small study; and wide confidence intervals and indirectness due to the study including male participants only. No study compared laparoscopic repair (total or hand-assisted) with open surgical repair or total laparoscopic surgical repair with EVAR.

AUTHORS' CONCLUSIONS

There is insufficient evidence to draw any conclusions about effectiveness and safety of laparoscopic (total and hand-assisted) surgical repair of AAA versus open surgical repair or EVAR, because only one small randomised trial was eligible for inclusion in this review. High-quality randomised controlled trials are needed.

Endovascular management for peripheral arterial trauma: The new norm?

BACKGROUND

Endovascular therapy is well studied in atraumatic conditions; and there appears to be a growing interest in its application to traumatic injuries. The objective of this study is to compare open and endovascular techniques in the management of peripheral arterial trauma.

METHODS

This is a retrospective review of patients admitted to a Level I Trauma Center sustaining injuries to the subclavian, axillary, superficial femoral, and popliteal arteries. Demographics, surgical interventions, complications, and clinical outcomes were evaluated in patients requiring open or endovascular repair between 2009 and 2015.

RESULTS

Sixty-eight patients with 70 total arterial injuries were identified. There were 10 subclavian, 14 axillary, 15 superficial femoral, and 31 popliteal artery injuries. Endovascular (n=20) compared to open repairs (n=50) were more commonly performed: by vascular surgeons (90% vs. 54%, p=0.01); in older patients (median age: 38 years vs. 25, p=0.01); primarily involving upper extremity injuries (60% vs. 24%, p=0.01). Furthermore, endovascular repairs less commonly required fasciotomy (15% vs. 46%, p=0.03) and trended towards lower transfusion requirements (50% vs. 77%, p=0.06). Patients undergoing open repair had lower pre-hospital systolic blood pressures (110 vs. 120, p=0.03) and lower initial hematocrit (31.5 vs. 36.2, p=0.02). However, outcomes between groups were trending higher in the endovascular group with respect to limb salvage rates at discharge (94% vs. 89%), median length of stay (14days vs. 9), and median follow-up (288days vs. 92) compared to the open group, but the data were not statistically significant. There was increasing utilization of endovascular repair over time (7% of total procedures in 2009; 50% in 2014).

CONCLUSIONS

Overall, endovascular and open techniques were not statistically different in early outcomes. Endovascular therapy appears to provide some advantage when it comes to: challenging anatomy, decreasing blood product utilization, and minimizing physiologic derangement. However, patients with injuries resulting in free hemorrhage or significant external blood loss may still be best served with open repair. Despite this, given the increasing use of endovascular techniques, close collaboration is needed between trauma and endovascular specialists to properly select the optimal management for patients with peripheral arterial trauma.

[Patient volume and quality in surgery for abdominal aortic aneurysm]

BACKGROUND Patient volume is assumed to affect quality, whereby complex procedures are best performed by those who perform them frequently. We have conducted a systematic review of the research on the association between patient volume and quality of vascular surgery. In this article we describe the outcomes for abdominal aortic aneurysm surgery.MATERIAL AND METHOD We undertook systematic searches in relevant databases. We searched for systematic reviews, and randomised and observational studies. The search was concluded in December 2015. We have summarised the results descriptively and assessed the overall quality of the evidence.RESULTS Forty-six observational studies fulfilled our inclusion criteria. We found a possible association for both hospital and surgeon volume. Higher patient volume may possibly be associated with lower 30-day mortality and lower hospital mortality for both open and endovascular surgery. Although the association appears to apply to both elective and acute hospitalisations, there is greater uncertainty with regard to the most ill patients. For hospital volume there may also be fewer complications for open and endovascular surgery, as well as for all surgery assessed as a whole. We considered the evidence base to be medium to very low quality.INTERPRETATION We found a possible correlation between patient volume and quality indicators such as mortality and complications. It may be advantageous to allocate planned procedures to institutions and surgeons with high volume, while this is less certain with regard to acute hospitalisations.

A mathematical model of aortic aneurysm formation

Abdominal aortic aneurysm (AAA) is a localized enlargement of the abdominal aorta, such that the diameter exceeds 3 cm. The natural history of AAA is progressive growth leading to rupture, an event that carries up to 90% risk of mortality. Hence there is a need to predict the growth of the diameter of the aorta based on the diameter of a patient’s aneurysm at initial screening and aided by non-invasive biomarkers. IL-6 is overexpressed in AAA and was suggested as a prognostic marker for the risk in AAA. The present paper develops a mathematical model which relates the growth of the abdominal aorta to the serum concentration of IL-6. Given the initial diameter of the aorta and the serum concentration of IL-6, the model predicts the growth of the diameter at subsequent times. Such a prediction can provide guidance to how closely the patient’s abdominal aorta should be monitored. The mathematical model is represented by a system of partial differential equations taking place in the aortic wall, where the media is assumed to have the constituency of an hyperelastic material.

Midterm Results of Endovascular Infrarenal Abdominal Aortic Aneurysm Repair in High-Risk Patients

Short-term and midterm clinical outcomes after endovascular repair of abdominal aortic aneurysms (AAAs) have been well documented. Evaluation of longer term outcomes is now possible. Here we describe our initial 100 high-risk patients treated with endovascular aneurysm repair (EVAR), all with a minimum of 5 years of follow-up. A retrospective review of prospectively recorded data in a departmental database was undertaken for the first 100 consecutive EVAR patients with a minimum of 5 years (range, 60-105 months) of follow-up performed between December 1997 and June 2001. Information was obtained from surgical follow-up visits and family doctors' offices. Endovascular repair of AAA in high-risk patients can be achieved with acceptably low postoperative mortality and morbidity. Longer term results in this high-risk cohort suggest that EVAR is effective in preventing aneurysm-related deaths at 5 years and beyond. All late mortalities were due to patients' comorbid diseases.

Concomitant abdominal aortic aneurysm and gastrointestinal malignancy: evolution of treatment paradigm in the endovascular era - review article

The incidence of concomitant abdominal aortic aneurysm and gastrointestinal malignancy is rare. Current treatment strategies in patients with both lesions remain controversial. It is unclear whether to treat the AAA and gastrointestinal malignancy simultaneously or in a staged manner. In patients with concomitant AAA and gastrointestinal malignancy surgical orthodoxy dictates that the most symptomatic lesion or the most life threatening condition should be treated first, however there is a therapeutic dilemma when neither or both of the lesions are symptomatic .In this review we explore (a) Priority of treatment in patients with concomitant abdominal aortic aneurysm and gastrointestinal malignancy (b) The role of EVAR in the management of abdominal aortic aneurysm and concomitant gastrointestinal malignancy.

Differences in readmissions after open repair versus endovascular aneurysm repair

OBJECTIVE

Reintervention rates after repair of abdominal aortic aneurysm (AAA) are higher for endovascular repair (EVAR) than for open repair, mostly due to treatment for endoleaks, whereas open surgical operations for bowel obstruction and abdominal hernias are higher after open repair. However, readmission rates after EVAR or open repair for nonoperative conditions and complications that do not require an intervention are not well documented. We sought to determine reasons for all-cause readmissions within the first year after open repair and EVAR.

METHODS

Patients who underwent elective AAA repair in California during a 6-year period were identified from the Health Care and Utilization Project State Inpatient Database. All patients who had a readmission in California ≤1 year of their index procedure were included for evaluation. Readmission rates and primary and secondary diagnoses associated with each readmission were analyzed and recorded.

RESULTS

From 2003 to 2008, there were 15,736 operations for elective AAA repair, comprising 9356 EVARs (60%) and 6380 open repairs (40%). At 1 year postoperatively, the readmission rate was 52.1% after open repair and 55.4% after EVAR (P=.0003). The three most common principle diagnoses associated with readmission after any type of AAA repair were failure to thrive, cardiac issues, and infection. When stratified by repair type, patients who underwent open repair were more likely to be readmitted with primary diagnoses associated with failure to thrive, cardiac complications, and infection compared with EVAR (all P<.001). Those who underwent EVAR were more likely, however, to be readmitted with primary diagnoses of device-related complications (P=.05), cardiac complications, and infection.

CONCLUSIONS

Total readmission rates within 1 year after elective AAA repair are greater after EVAR than after open repair. Reasons for readmission vary between the two cohorts but are related to the magnitude of open surgery after open repair, device issues after EVAR, and the usual cardiac and infectious complications after either intervention. Systems-based analysis of these causes of readmission can potentially improve patient expectations and care after elective aneurysm repair.

The impact of using informative priors in a Bayesian cost-effectiveness analysis: an application of endovascular versus open surgical repair for abdominal aortic aneurysms in high-risk patients

BACKGROUND

Bayesian methods have been proposed as a way of synthesizing all available evidence to inform decision making. However, few practical applications of the use of Bayesian methods for combining patient-level data (i.e., trial) with additional evidence (e.g., literature) exist in the cost-effectiveness literature. The objective of this study was to compare a Bayesian cost-effectiveness analysis using informative priors to a standard non-Bayesian nonparametric method to assess the impact of incorporating additional information into a cost-effectiveness analysis.

METHODS

Patient-level data from a previously published nonrandomized study were analyzed using traditional nonparametric bootstrap techniques and bivariate normal Bayesian models with vague and informative priors. Two different types of informative priors were considered to reflect different valuations of the additional evidence relative to the patient-level data (i.e., "face value" and "skeptical"). The impact of using different distributions and valuations was assessed in a sensitivity analysis. Models were compared in terms of incremental net monetary benefit (INMB) and cost-effectiveness acceptability frontiers (CEAFs).

RESULTS

The bootstrapping and Bayesian analyses using vague priors provided similar results. The most pronounced impact of incorporating the informative priors was the increase in estimated life years in the control arm relative to what was observed in the patient-level data alone. Consequently, the incremental difference in life years originally observed in the patient-level data was reduced, and the INMB and CEAF changed accordingly.

CONCLUSIONS

The results of this study demonstrate the potential impact and importance of incorporating additional information into an analysis of patient-level data, suggesting this could alter decisions as to whether a treatment should be adopted and whether more information should be acquired.

Medical treatment for small abdominal aortic aneurysms

BACKGROUND

Screening for abdominal aortic aneurysm (AAA) in selected groups is now performed in England, the USA and Sweden. Patients with aneurysms over 55 mm in diameter are generally considered for elective surgical repair. Patients with aneurysm diameters below or equal to 55 mm (termed 'small AAAs') are managed with aneurysm surveillance as there is currently insufficient evidence to recommend surgery in these cases. As more patients are screened, there will be an increasing number of small AAAs identified. There is interest in pharmaceutical interventions (for example angiotensin converting enzyme (ACE) inhibitors, antibiotics, beta-blockers, statins) which could be given to such patients to delay or reverse aneurysm expansion and reduce the need for elective surgical repair.

OBJECTIVES

To assess the effects of medical treatment on the expansion rate of small abdominal aortic aneurysms.

SEARCH METHODS

The Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (May 2012) and CENTRAL (2012, Issue 5). Clinical trials databases were searched for details of ongoing or unpublished studies. The reference lists of articles retrieved by electronic searches were searched for additional citations.

SELECTION CRITERIA

We selected randomised trials in which patients with small AAAs allocated to medical treatment with the intention of retarding aneurysm expansion were compared to patients allocated to a placebo treatment, alternative medical treatment, a different regimen of the same drug or imaging surveillance alone.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data and assessed the risk of bias in the trials. Meta-analyses were used when heterogeneity was considered low. The two primary outcomes were the mean difference (MD) in aneurysm diameter and the odds ratio (OR) calculated to compare the number of individuals referred to AAA surgery in each group over the trial period.

MAIN RESULTS

Seven trials involving 1558 participants were included in this review; 457 were involved in four trials of antibiotic medication, and 1101 were involved in three trials of beta-blocker medication. Five of the studies were rated at a high risk of bias.Individually, all of the included trials reported non-significant differences in AAA expansion rates between their intervention and control groups.The two major drug groups were then analysed separately. For AAA expansion it was only possible to combine two of the antibiotic trials in a meta-analysis. This demonstrated that roxithromycin had a small but significant protective effect (MD -0.86 mm; 95% confidence interval (CI) -1.57 to -0.14). When referral to AAA surgery was compared (including all four antibiotic trials in the meta-analysis), non-significantly fewer patients were referred in the intervention groups (OR 0.96; 95% CI 0.59 to 1.57) than the control groups. When only the trials reporting actual elective surgery were included in a subgroup analysis, the result remained statistically non-significant (OR 1.17; 95% CI 0.57 to 2.42).For the beta-blocker trials, when all were combined in a meta-analysis, there was a very small, non-significant protective effect for propranolol on AAA expansion (MD -0.08 mm; 95% CI -0.25 to 0.10), and non-significantly fewer patients were referred to AAA surgery in the propranolol group (OR 0.74; 95% CI 0.52 to 1.05). Bronchospasm and shortness of breath were the main adverse effects from the beta-blockers. In one trial the adverse effects were reportedly so severe that the trial was stopped early after two years.

AUTHORS' CONCLUSIONS

There is some limited evidence that antibiotic medication may have a slight protective effect in retarding the expansion rates of small AAAs. The quality of the evidence makes it unclear whether this translates into fewer referrals to AAA surgery, owing mainly to the small sample sizes of the studies.Antibiotics were generally well tolerated with minimal adverse effects. Propranolol was poorly tolerated by patients in all of the beta-blocker trials and demonstrated only minimal and non-significant protective effects. Further research on beta-blockers for AAA needs to consider the use of drugs other than propranolol.In general, there is surprisingly little high quality evidence on medical treatment for small AAAs, especially in relation to the use of newer beta-blockers, ACE inhibitors and statins.

An update on the 'fast-track' abdominal aortic aneurysm repair

Patients who have unfavourable anatomy for endovascular repair of an abdominal aortic aneurysm require open repair. This is particularly the case for juxtarenal aortic aneurysms, or those patients with small or occluded iliac access vessels.An experience of 'fast-track' abdominal aortic aneurysm repair that was previously reported is updated in the present case. A retroperitoneal approach to the aorta is taken, using a small incision, and is followed by a patient care pathway protocol that demonstrated excellent results and a shortened length of stay. The present update on 56 patients is approximately double the previously reported experience.

A comparative study of the bell-bottom technique vs hypogastric exclusion for the treatment of aneurysmal extension to the iliac bifurcation

INTRODUCTION

A significant proportion of patients undergoing endovascular aneurysm repair (EVAR) have common iliac artery aneurysms (CIAA). Aneurysmal involvement at the iliac bifurcation potentially undermines long-term durability.

METHODS

Patients with CIAA who underwent EVAR were identified in two teaching hospitals. Bell-bottom technique (BBT; iliac limb ≥20 mm) or internal iliac artery embolization and limb extension to the external iliac artery (IIE + EE) were used. Outcome between these two approaches was compared.

RESULTS

We identified 185 patients. Indication for EVAR included asymptomatic abdominal aortic aneurysm (AAA) in 157, symptomatic or ruptured aneurysm in 19, and CIAA in nine. Mean AAA diameter was 59 mm. Among 260 large CIAAs that were treated, BBT was used to treat 166 CIAA limbs, and 94 limbs underwent IIE + EE. Total reintervention rates were 11% for BBT (n = 19) and 19.1% for IIE + EE (n = 18; P = .149). Rates of reintervention for type Ib or III endoleak were 4% for BBT (n = 7) and 4% for IIE + EE (n = 4; P > .99). The difference in limb patency rates was not significant. The 30-day mortality rate was 1%. Median follow-up was 22 months. Complications did not differ significantly between the two groups; however, the combined incidence of perioperative complications and reinterventions was higher in the IIE + EE group (49% vs 22%; P = .002).

CONCLUSIONS

The combined incidence of perioperative complications and reinterventions is significantly higher with IIE + EE than with BBT; therefore, when feasible, BBT is desirable.

Long-term outcomes of endovascular aneurysm repair for challenging aortic necks using the Talent endograft

The aim of the present paper is to evaluate the long-term outcomes of endovascular aneurysm repair (EVAR) for challenging aortic necks. Subgroup analyses were performed on 156 patients from the prospective multicenter Talent eLPS (enhanced Low Profile Stent Graft System) trial. Patients with high-risk aortic necks (length < 15 mm or diameter ≥28 mm) were compared with the remaining patients. Patients with high-risk (n = 86) and low-risk necks (n = 70) had similar age and gender distribution. Despite similar prevalences of co-morbidities, the high-risk group had higher Society for Vascular Surgery scores. The high-risk group also had larger maximum aneurysm diameters (56.6 versus 53.0 mm, P < 0.02). There were lower freedoms from major adverse events (MAEs) for the high-risk group at 30 days (84.9 versus 95.7%; P < 0.04) and 365 days (73.4 versus 89.2%; P = 0.02). Effectiveness endpoints at 12 m showed no significant differences. Freedom from all-cause mortality at 30 days (96.5 versus 100%) and aneurysm-related mortality at 365 days (96.0 versus 100%) were similar. At five years, there were no differences in endoleaks or change in aneurysm diameter. All migrations occurred in the high-risk group. The five-year freedom from aneurysm-related mortality for the high- and low-risk groups was 93.2 and 100%, respectively. In conclusion, despite a higher rate of MAEs within the first year and higher migration rates at five years, EVAR in aneurysms with challenging aortic necks can be treated with acceptable long-term results.

A 5-year evaluation using the talent endovascular graft for endovascular aneurysm repair in short aortic necks

BACKGROUND

Although endovascular aneurysm repair has been shown to be an effective way to treat abdominal aortic aneurysm (AAA), certain anatomic characteristics such as a short aortic neck, limit its applicability. Initially, commercially available devices were approved only for the treatment of AAA with an aortic neck length ≥ 15 mm. The purpose of this study was to evaluate the outcomes of the recently approved Talent endograft for AAAs with a short aortic neck length (10-15 mm).

METHOD

Data were obtained from the prospective, nonrandomized, multicenter Talent enhanced Low Profile Stent Graft System trial which enrolled patients between February 2002 and April 2003. A total of 154 patients with adequate preoperative imaging were identified for this study. Subgroup analyses were performed for AAA with 10-15 mm aortic neck and those with >15 mm neck. Safety and effectiveness endpoints were evaluated at 30 days, 1 year, and 5 years postprocedure.

RESULTS

Patients treated with aortic neck lengths of 10-15 mm (n = 35) and those with >15 mm (n = 102) had similar age, gender, and risk factor profile. Both groups had similar preoperative aneurysm morphology in terms of maximum aneurysm size, degree of neck angulation, or proximal neck diameter. There were no statistically significant differences in freedom from major adverse events and mortality rates at 30 and 365 days. Similarly, there was no difference in the effectiveness endpoints at 12 months. At 5 years, there was no difference in migration rate, endoleaks, or change in aneurysm diameter from baseline. In addition, there is no difference in freedom from aneurysm-related mortality (94% vs. 99%).

CONCLUSIONS

AAAs with short aortic necks (10-15 mm) and otherwise suitable anatomy for endovascular repair can be safely and effectively treated with the Talent endograft with excellent 1 and 5 year outcomes.

Tratamento endovascular de pseudoaneurisma de aorta torácica: relato de caso

Paciente de 31 anos vítima de acidente automobilístico apresentou falta de ar inspiratória progressiva acompanhada de dor dissecante no tórax, de forte intensidade, sem irradiação; Glasgow 15 e ISS 26 (16 + 9 + 1); exames laboratoriais e radiográficos compatíveis com a normalidade. Foi operado de fratura de tíbia 1 dia depois, tendo recebido alta 3 dias depois da entrada no serviço. No entanto, foi piorando da falta de ar e da dor torácica, retornando para nova consulta 2 dias após a alta hospitalar. Foi realizada tomografia computadorizada helicoidal que revelou pseudoaneurisma de aorta torácica. Optou-se por tratamento endovascular com implante de endoprótese.

Five-year results for the Talent enhanced Low Profile System abdominal stent graft pivotal trial including early and long-term safety and efficacy

OBJECTIVES

The pivotal trial of the Talent enhanced Low Profile System (eLPS; Medtronic Vascular, Santa Rosa, Calif) stent graft evaluated short and long-term safety and efficacy of endovascular aneurysm repair (EVAR). These data and a confirmatory group assessing the performance of the CoilTrac delivery system supported the United States premarket approval application for the device.

METHODS

The pivotal trial was a prospective, nonrandomized study conducted at 13 sites from February 2002 to April 2003. The study group (n = 166) underwent EVAR using the Talent eLPS stent graft. The control group (n = 243) underwent open surgical AAA repair. Data for this group were obtained from the Society for Vascular Surgery Endovascular AAA Surgical Controls project. Outcomes were compared at 30 days and 12 months. Additional 5-year follow-up was obtained for the eLPS group. A single-center cohort of 137 patients was the confirmatory group for the assessment of the clinical performance of the CoilTrac delivery system, with analysis of outcomes <or=30 days from the procedure.

RESULTS

AAA anatomy with neck length as short as 3 mm and maximum neck diameter of 32 mm were included in the eLPS group. EVAR was superior to open repair for periprocedural outcomes, including mean procedure duration (167.3 vs 196.4 minutes, P < .001), blood transfusion (18.2% vs 56.8%, P < .001), median intensive care unit stay (19.3 vs 74.3 hours, P < .001), and mean hospital stay (3.6 vs 8.2 days, P < .001). Freedom from major adverse events was 89.2% for EVAR at 30 days vs 44.0% (P < .001) and 81.3% vs 42.4% at 1 year (P < .001). Freedom from all-cause mortality and aneurysm-related mortality (ARM) was 93.7% and 98.2% for EVAR vs 92.4% and 96.7% for the controls. Through 5 years for the EVAR group, rates of freedom from all-cause mortality, ARM, aneurysm rupture, and conversion to surgery were 69.8%, 96.5%, 98.2%, and 99.1%, respectively, with one conversion to surgery, 25 secondary reinterventions, and five site-reported instances of stent graft migration. The technical success rate for the CoilTrac confirmatory group was 100%, with no aneurysm rupture or conversion to open repair at 30 days. The 30-day all-cause mortality rate was 1.5% (2 of 137).

CONCLUSIONS

In a population with challenging anatomic characteristics, EVAR with the Talent eLPS and use of the CoilTrac delivery system compared favorably with open repair through 1 year. Sustained protection from ARM, with minimal reinterventions, was attained through 5 years.

Infrarenal Abdominal Aortic Aneurysm with Concomitant Urologic Malignancy: Treatment Results in the Era of Endovascular Aneurysm Repair

During diagnostic workup for urologic malignancies, an abdominal aortic aneurysm (AAA) is identified in a proportion of patients. In the era of open AAA repair, these patients presented a surgical dilemma with regard to the sequence of the operations: cancer treatment first or AAA repair first? Previous assessments have concluded that irrespective of the followed strategy, the early and mediumterm mortality from the two operative procedures in this patient category was significant. With the introduction of endovascular aneurysm repair (EVAR), the mortality and morbidity associated with the treatment of both pathologic conditions may be more favorable than with open aneurysm repair. The objective of this study was to assess, in an institutional series of patients receiving EVAR, the early and long-term survival and complication rates in patients with urologic malignancies. In a series of 385 patients receiving EVAR, 14 had a concomitant urologic malignancy: renal cell carcinoma (5 patients), prostate carcinoma (6 patients), and carcinoma of the bladder (3 patients). The first-month mortality was nil. Long-term survival was 80%, 83%, and 67% for the three tumor types, respectively. EVAR offers improved treatment in patients with concomitant AAA and urologic malignancy and should be considered the first choice for these patients.

Outcomes of care of abdominal aortic aneurysm in Veterans Health Administration facilities: results from the National Surgical Quality Improvement Program

This report describes outcomes of care for abdominal aortic aneurysms (AAAs), along with methods used by the Veterans Affairs (VA) National Surgical Quality Improvement Program (NSQIP) in tracking, monitoring, and improving surgical results in VA facilities. Since the inception of NSQIP in 1994, a continual drop in overall surgical mortality, along with decreased morbidity, has occurred. A parallel improvement in results of vascular surgery and AAA repair was also observed. Soon after introduction of endovascular aneurysm repair (EVAR), with Food and Drug Administration device approval in 1999, robust electronic NSQIP records immediately began to capture individual facility performances and outcomes for both types of AAA repair. The NSQIP data center provided actual and risk-adjusted analyses for both procedures semiannually. These analyses have been used by its executive board to provide recommendations, often based on site visits, to improve outcomes. Requirements for reporting of facility-specific data and feedback, paper audits, and site visits appear to relate directly to improved AAA care. Veterans Health Administration (VHA) outcomes of AAA repair are comparable to those reported nationally and internationally and have continued to improve in recent years. National VHA initiatives, based on data feedback and active oversight, relate to some of the lowest AAA mortality rates available. This review describes past, present, and possible future NSQIP strategies to improve outcomes for AAA repair with general comments about recent alternative proposals.

Estudo comparativo entre tratamento endovascular e cirurgia convencional na correção eletiva de aneurisma de aorta abdominal: revisão bibliográfica

O tratamento eletivo do aneurisma de aorta abdominal é recomendado pela alta morbiletalidade decorrente da eventual ruptura. O objetivo deste trabalho foi comparar o reparo endovascular eletivo com a cirurgia aberta e avaliar as mortalidades hospitalar e perioperatória, em 1 ano, por todas as causas e relacionadas ao aneurisma, a permanência hospitalar, as complicações, as taxas de sobrevida, conversão e reintervenção, a durabilidade do enxerto, o custo-benefício e a relação desses dados com o treinamento da equipe médica responsável pelo tratamento. Realizou-se uma revisão da literatura sobre reparo endovascular versus cirurgia convencional. Foram observados vantagem na sobrevivência perioperatória e menor estresse pós-cirúrgico; no entanto, os benefícios iniciais são perdidos por complicações e reintervenções tardias. Trabalhos baseados nas primeiras gerações de endopróteses superestimam as taxas de mortalidade em curto prazo, complicações e reintervenções. A durabilidade do enxerto, a real vantagem na sobrevida e o custo-benefício são incertos, e outros estudos são necessários para o seguimento em longo prazo.

Changing Indications and Outcomes for Open Abdominal Aortic Aneurysm Repair since the Advent of Endovascular Repair

The indications for open abdominal aortic aneurysm (AAA) repair have changed with the development of endovascular techniques. The purpose of this study is to clarify the indications and outcomes for open repair since endovascular aneurysm repair (EVAR) and to compare contemporary AAA repair with the pre-EVAR era. Patients undergoing open AAA repair were identified; the demographics, outcomes, and indications for open repair were reviewed. Outcomes were compared based on indication for open repair in the EVAR era and between the pre-EVAR and EVAR eras. Open indications in the EVAR era included: age younger than 65 years with minimal comorbidities (AGE, n = 24 [9.8%]), unfavorable anatomy (ANAT, n = 146 [59.3%]), aortoiliac occlusive disease (AIOD, n = 38 [15.4%]), and miscellaneous (OTHER, n = 38 [15.4%]). Mortality (30-day and 5-year) was affected by indication: AGE = 0 and 0 per cent, ANAT = 4.1 and 49.7 per cent, AIOD = 13.5 and 32.3 per cent, and OTHER = 5.3 and 41.8 per cent. Age, sex, race, coronary artery disease, and peripheral artery disease were similar between the pre-EVAR and EVAR eras. EVAR-era patients had more diabetes mellitus, hypertension, and hyperlipidemia and longer operative time. Mortality was not different, but complication rates were lower in the pre-EVAR era (23.7 vs 43.5%, P = 0.025). Patients undergoing open AAA repair in the EVAR era have more comorbidities, longer operative times, and more complications. Outcomes for EVAR-era patients are affected by the indication for open repair. A preference for open repair in younger patients with minimal comorbidities is justified.

Concurrent colorectal malignancy and abdominal aortic aneurysm: a multicentre experience and review of the literature

OBJECTIVES

There is lack of consensus regarding concurrent vs. staged approaches, and the prioritisation of staged procedures in cases presenting with colorectal carcinoma (CRC) and abdominal aortic aneurysm (AAA) synchronously. We aim to present our experience, review the literature on this therapeutic dilemma and examine the role of endovascular aortic repair (EVAR).

DESIGN, MATERIALS AND METHODS

An observational study of the experience of two centres and a systematic review of the published literature.

RESULTS

Twenty-four patients were identified from the prospective databases of two tertiary referral centres between 2001 and 2006. Intervention for both malignancy and aneurysm was performed in 13 patients. In 10 patients, cancer resection was performed initially and was followed by open aneurysm repair (n=3) or EVAR (n=7). Two patients (AAA diameters: 7.0 and 8.0cm) underwent EVAR prior to colonic resection. One patient was selected for synchronous surgery. There were no interval AAA ruptures, graft infection or postoperative mortalities. Literature review identified 269 such cases; of these 101 were treated by combined surgery. In staged surgery, there were nine interval aneurysmal ruptures and one aortic graft infection.

CONCLUSIONS

In our experience, staged management can be undertaken, without interval aneurysmal rupture. EVAR has an evolving role in preventing delay in CRC management, in high-risk patients, and during combined intervention.

Effects of study design and trends for EVAR versus OSR

Purpose:

To investigate if study design factors such as randomization, multi-center versus single center evidence, institutional surgical volume, and patient selection affect the outcomes for endovascular repair (EVAR) versus open surgical repair (OSR). Finally, we investigate trends over time in EVAR versus OSR outcomes.

Methods:

Search strategies for comparative studies were performed individually for: OVID’s MEDLINE, EMBASE, CINAHL, HAPI, and Evidence Based Medicine (EBM) Reviews (including Cochrane DSR, ACP Journal Club, DARE and CCTR), limited to 1990 and November 2006.

Results:

Identified literature: 84 comparative studies pertaining to 57,645 patients. These include 4 randomized controlled trials (RCTs), plus 2 RCTs with long-term follow-up. The other 78 comparative studies were nonrandomized with 75 reporting perioperative outcomes, of which 16 were multi-center, and 59 single-center studies. Of the single-center studies 31 were low-volume and 28 were high-volume centers. In addition, 5 studies had all patients anatomically eligible for EVAR, and 8 studies included high-risk patients only. Finally, 25 long term observational studies reported outcomes up to 3 years.

Outcomes:

Lower perioperative mortality and rates of complications for EVAR versus OSR varied across study designs and patient populations. EVAR adverse outcomes have decreased in recent times.

Conclusion:

EVAR highlights the problem of performing meta-analysis when the experience evolves over time.

Endovascular Abdominal Aortic Aneurysm Repair: A Community Hospital's Experience

Endovascular abdominal aortic aneurysm repair (EVAR) has become the first-line approach for the treatment of abdominal aortic aneurysms. Outcomes outside of tertiary care settings remain unknown. The purpose of this study is to report the midterm outcomes of EVAR in a community hospital. A retrospective review of 75 elective, consecutive EVARs performed at a single nonacademic community hospital was performed. There were no conversions to open repair during or after endovascular repair. The mean follow-up was 18 months. There were no postoperative ruptures or aneurysm-related deaths. At 24 months, freedom from aneurysm-related death was 100%, freedom from secondary interventions was 91%, and freedom from endoleak was 69%. EVAR in the community setting is a safe and durable procedure, even in a medically high-risk population. Comparable outcomes can be achieved to tertiary care centers, in carefully selected patients with favorable anatomy.

A single-institution experience with the AneuRx Stent Graft for endovascular repair of abdominal aortic aneurysm

We report our experience of endovascular repair of infrarenal abdominal aortic aneurysms (EVAR) using the modular AneuRx Stent Graft System. We retrospectively reviewed the outcomes of 113 patients who underwent EVAR with the AneuRx system performed at our institution between October 1999 and August 2003. The mean age of this group was 72.5 years, with 71% (n = 80) over the age of 70 years and 95% (n = 107) males. Aneurysm diameter ranged 4.0-9.0 cm, with 33% (n = 37) >6.0 cm. The average duration of late follow-up was 32.6 +/- 24.8 months (median = 37). Successful deployment of the modular AneuRx system was noted in all patients. There were no immediate operative conversions, deaths within 24 hr of operation, or type I or III endoleaks observed at the completion of the procedure. Thirty-day mortality was 3.5% (n = 4). Acute deployment-related complications occurred in 10% (n = 13) of patients and included misdeployment, operative bleeding, arterial perforation/dissection, and access site complications. Acute systemic complications were present in nine patients, predominantly renal and cardiac complications. An endoleak noted at any time occurred in 25% of patients, with 40% of those requiring a secondary intervention. Two patients suffered late aneurysm rupture due to a type I endoleak and graft infection. Kaplan-Meier analysis revealed 5-year freedom from secondary intervention of 72.4%; freedom from aneurysm-related death of 93.9%; and probability of survival based on all-cause mortality of 60.1%. Endovascular treatment with the modular AneuRx Stent Graft System is safe and effective, producing acceptable rates of disease-free survival and mid-term clinical outcome.

A meta-analysis of 21 178 patients undergoing open or endovascular repair of abdominal aortic aneurysm

Background

Several studies have compared outcomes after elective open and endovascular approaches to abdominal aortic aneurysm (AAA) surgery, with varying results.

Methods

A random-effects meta-analysis was undertaken to compare operative outcomes, postoperative complications, 30-day mortality and long-term patient survival after surgery. Endpoints were compared using odds ratios (ORs), weighted mean differences (WMDs) or log hazard ratios (HRs) as appropriate.

Results

Forty-two studies comprising 21 178 patients (10 855 open; 10 323 endovascular) were included. In the elective setting (20 715 patients), the endovascular method was associated with a shorter stay in intensive care (WMD − 36 h; P &lt; 0·001) and a shorter total postoperative stay (WMD − 5·4 days; P &lt; 0·001). Cardiac (OR 1·76; P = 0·002) and respiratory (OR 4·01; P &lt; 0·001) complications were more common after open surgery. In the endovascular group, 30-day mortality was lower (OR 0·46; P &lt; 0·001). Endovascular surgery was also associated with an improved long-term aneurysm-related mortality (HR 0·39; P &lt; 0·001). For ruptured AAA (463 patients), the less invasive operation was associated with a reduced stay in intensive care (WMD − 100·4 h; P = 0·005) and a significantly lower 30-day mortality (OR 0·45; P = 0·005).

Conclusions

The endovascular repair of AAA offers a clear benefit in terms of reduction in postoperative adverse events and 30-day mortality. In the longer term, it is also associated with a reduction in aneurysm-related mortality, but not in all-cause mortality.