Cost-effectiveness of endovascular abdominal aortic aneurysm repair

BACKGROUND: The rapid introduction of endovascular abdominal aortic aneurysm repair (EVAR) has considerable implications for the management of abdominal aortic aneurysm (AAA). This study was undertaken to determine an optimal strategy for the use of EVAR based on the best currently available evidence. METHODS: Economic modelling and probabilistic sensitivity analysis considered reference cases representing a fit 70-year-old with a 5.5-cm diameter AAA (RC1) and an 80-year-old with a 6.5-cm AAA unfit for open surgery (RC2). Results were assessed as incremental cost-effectiveness ratio (ICER) compared with open repair (RC1) or conservative management (RC2). RESULTS: In RC1 EVAR produced a gain of 0.10 quality-adjusted life years (QALYs) for an estimated cost of 11,449 pound, giving an ICER of 110,000 pound per QALY. EVAR consistently had an ICER above 30,000 pound per QALY over a range of sensitivity analyses and alternative scenarios. In RC2 EVAR produced an estimated benefit of 1.64 QALYs for an incremental cost of 14,077 pound giving an incremental cost per QALY of 8579 pound. CONCLUSION:: It is unlikely that EVAR for fit patients suitable for open repair is within the commonly accepted range of cost-effectiveness for a new technology. For those unfit for conventional open repair it is likely to be a cost-effective alternative to non-operative management. Sensitivity analysis suggests that research efforts should concentrate on determining accurate rates for late complications and reintervention, particularly in patients with high operative risks.     

Percutaneous endovascular repair of infrarenal abdominal aortic aneurysms: a feasibility study

BACKGROUND: Endovascular grafting has markedly reduced the invasiveness of the treatment of abdominal aortic aneurysms. By using a modification of technique for available closure devices, we have been able to achieve percutaneous repair of aneurysms. This study reviewed our initial experience with this technique. METHODS: Demographics and background data from patients undergoing endovascular repair of abdominal aortic aneurysms were reviewed from prospectively collected registry data. Operative notes and angiographic and computed tomography scan data were retrospectively reviewed to assess the success of the percutaneous approach. RESULTS: Fourteen patients have undergone percutaneous placement of the AneuRx (Medtronic, Sunnyvale, Calif) endovascular graft, with a modification of the technique for the Prostar (Perclose, Redwood City, Calif) device for access site closure. Main graft body introduction with a 22F sheath proved successful in nine of 12 (75%) deployments. Contralateral limb deployment through a 16F sheath was successful in 10 of 14 deployments (71.4%). Reasons for conversion to open groin incisions include inadequate percutaneous hemostasis (six cases), iliofemoral dissection (four cases), device failure (one case), and compromised distal flow (one case). Percutaneous deployment success appears to be improved with larger iliac artery dimensions, decreased calcification, and limited tortuosity, because of the limitation of complications related to delivering a larger diameter sheath. Of the 13 percutaneous endograft insertions that were attempted, six (46.2%) were completely successful. CONCLUSION: Percutaneous deployment of available devices is technically feasible by using modifications of technique with percutaneous closure devices, despite large introducer sizes. Further experience with this technique offers the potential for identifying patients in whom this will prove successful and for even further reducing hospital stay and recovery times for aneurysm repair.     

Current outcomes in endovascular repair of abdominal aortic aneurysms

The repair of abdominal aortic aneurysms has presently been reported to be accomplished using endovascular techniques in 60% of the cases. As technology continues to improve on the design of endovascular devices, this will only result in a progressive upward trend of this innovative method. At this time, there are multiple commercial and investigational devices available. We elect to discuss current results pertaining to the optimal candidate, characteristics, complications, and the long-term durability of aortic stent-grafts.     

Embolic complications after endovascular repair of abdominal aortic aneurysms

Purpose

This retrospective study aimed to review our experiences with endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs), along with the incidence, risk factors and prognoses of associated embolic events. Our goal was to present the EVAR results and related risk factors from a single center, with a focus on embolic complications.

Methods

We retrospectively reviewed the data of 539 patients with AAAs who underwent elective EVAR at Jikei University from July 2006 to April 2009. Of these, 438 patients were selected after excluding those requiring fenestrated and branched EVAR.

Results

The technical success rate was 91.1 % (399/438) with no surgical mortality. Embolic complications occurred in nine patients (2 %), four of whom developed ischemic colitis and were successfully treated with bowel rest and hydration. Lower extremity atheroembolization and stroke occurred in three and one patients, respectively. Two patients died of cholesterol crystal embolization. Seven of the nine embolic complications (77.8 %) were associated with the use of Zenith stent-grafts. A Cox proportional-hazard regression analysis of the adjusted risk factors showed that smoking and severe arterial degeneration of the aorta, referred to as a shaggy aorta, to be independent predictors of embolic complications.

Conclusions

The presence of a shaggy aorta and a history of smoking are independent predictors of embolic complications associated with EVAR.     

Comparison of midterm results of endovascular aneurysm repair for ruptured and elective abdominal aortic aneurysms

ObjectiveEndovascular aneurysm repair (EVAR) became an increasingly preferred modality for abdominal aortic aneurysm (AAA) repair both in elective AAA repair (el-EVAR) and EVAR of a ruptured AAA (r-EVAR) setting. Ruptured AAAs usually have more hostile anatomies and less time for planning. Consequently, more complications may arise after r-EVAR. The purpose of this study was to compare mi-term outcomes between r-EVAR and el-EVAR.MethodsA retrospective cohort analysis of patients undergoing EVAR from 2000 to 2015 at a tertiary institution was performed. Patients with previous aortic surgery, nonatherosclerotic AAA and isolated iliac aneurysms were excluded. In-hospital casualties or patients who were intraoperatively converted to open repair were also excluded. For the midterm outcome analysis, only patients with at least two postoperative examinations (a 30-day computed tomography scan and a second postoperative examination performed 6 months or later) were considered. The primary end point was freedom from aneurysm-related complications (a composite of type I or III endoleak, aneurysm sac growth, migration of more than 5 mm, device integrity failure, AAA-related death, late postimplant rupture, or AAA-related secondary intervention). Freedom from secondary interventions, neck-related events (defined as a composite of type IA endoleak, migration of more than 5 mm, or preemptive neck-related secondary intervention) and late survival were secondary end points. The impact of device instructions for use (IFU) compliance on neck events was also assessed.ResultsThe study included 565 patients (65 r-EVAR and 500 el-EVAR). Eighty-two patients were treated outside proximal neck IFU, 13 in the r-EVAR group (21.3%) and 69 (14.5%) in the el-EVAR (P = .16). During the index hospitalization, there were more complications (12.3% vs 3.2%; P = .001) and reinterventions (12.3% vs 2.8%; P < .001) in the r-EVAR group. After discharge, median clinical follow-up time was 4.3 years (interquartile range, 2.1-7.0 years) without differences between both groups. Five-year freedom from AAA-related complications was 53.9% in the r-EVAR group and 65.4% in the el-EVAR (P = .21). In multivariable analysis the r-EVAR group was not at increased risk for late complications (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.54-1.61; P = .81). Five-year freedom from neck-related events was 74% in r-EVAR and 82% in the el-EVAR group (P = .345). Patients treated outside neck IFU were at greater risk for neck-related events both in r-EVAR (HR, 6.5; 95% CI, 1.8-22.9; P = .004) and el-EVAR group (HR, 2.6; 95% CI, 1.5-4.5; P < .001). Freedom from secondary interventions at 5 years was 63.0% for r-EVAR and 76.9% for el-EVAR (P = .16). Survival at 5 years was 68.8% in the r-EVAR group and 73.3% in the el-EVAR group (P = .30).ConclusionsDurable and sustainable midterm outcomes were found for both r-EVAR and el-EVAR patients who survived the postoperative period. Patients treated outside the IFU are at greater risk for late complications. Surveillance protocols may be tailored according to individual anatomy and IFU compliance rather than timing of repair.     

The outcome of endovascular repair of small abdominal aortic aneurysms

OBJECTIVE: To assess the outcome of endovascular repair (EVAR) of small abdominal aortic aneurysms (AAA, 相似文献   

Anesthesia for endovascular repair of abdominal and thoracic aortic aneurysms: a review article

Open repair of abdominal aortic aneurysms (AAA) and thoracic aortic aneurysms (TAA) are associated with significant morbidity and mortality. Endovascular aortic aneurysm repair (EVAAR) using a stent graft is a new alternative to traditional open repair. There are various types of anesthesia which can be utilized for EVAAR; specifically general endotracheal anesthesia, regional anesthesia, and monitored anesthesia care (MAC) with local anesthetic infiltrated at the incision site. Choice of anesthetic technique may be dependent upon a patient's co-existing diseases. We have prepared a review article discussing the various types of anesthesia available for this procedure, including the specifics of each technique and pros and cons of each option. The most often utilized technique appears to be general anesthesia, often times related to surgeon unfamiliarity with the EVAAR procedure. Regional techniques, including continuous epidural or continuous spinal anesthesia are utilized in some cases with very good results. This technique can provide more hemodynamic stability and better pain control than general alternative, MAC with local, is an extremely safe and effective technique for the EVAAR procedure, especially in patients with severe co-existing diseases. In addition, this technique also minimalizes sedation and post-operative analgesic requirements, decreases cardiopulmonary complications, and decreases overall hospital stay, thereby reducing cost.     

Midterm outcome of endovascular repair of ruptured abdominal aortic aneurysms

PURPOSE: We sought to analyze the clinical and morphologic outcomes of bifurcated stent grafts in patients with ruptured aortoiliac aneurysms at midterm follow-up. METHODS: Thirty-seven patients (4 women; mean age, 73 years; mean abdominal aortic aneurysm [AAA] diameter, 77 mm) underwent endovascular abdominal aneurysm repair between June 1997 and July 2003 for ruptured AAA. Devices inserted were as follows: Vanguard (Boston Scientific, Natick, Mass; n = 7), Excluder (W.L. Gore, Flagstaff, Ariz; n = 25), Talent (Medtronic Vascular, Santa Rosa, Calif; n = 2), and Zenith (Cook Inc, Bloomington, Ind; n = 3). Except for the adjunct postimplantation computed tomographic scanning, the imaging follow-up was the same as for nonruptured AAAs. RESULTS: The mean follow-up period was 24 months (range, 1-59) months. Thirty-day mortality was 10.8%. Three patients died during the follow-up of non-AAA-related causes. One patient was converted early for presumed renal overstenting. The late conversion rate was 9% because of stent graft migration (n = 2) or infection (n = 1). Freedom from endoleak was 57% +/- 8.5% and 48.8% +/- 9% at 2 and 4 years, respectively. Seventeen secondary interventions were performed during the follow-up period, 41% of these within 1 month of stent graft placement. Endoleaks, primary or secondary, were responsible for 58.8% of these interventions. The cumulative risk of a secondary intervention was 35.3% +/- 9% at 2 years and 44.6% +/- 11% at 3 years. Aneurysmal sac shrinkage was observed in 30.8% +/- 9.1% and sac enlargement was observed in 15.3% +/- 10.8% at 2 years. CONCLUSION: Endoluminal devices are able to convert the acute life-threatening situation of ruptured AAA to a controlled situation that results in good patient survival at midterm follow-up.     

Perioperative outcome of endovascular repair for complex abdominal aortic aneurysms

Background

As endovascular aneurysm repair (EVAR) continues to advance, eligibility of patients with anatomically complex abdominal aortic aneurysms (AAAs) for EVAR is increasing. However, whether complex EVAR is associated with favorable outcome over conventional open repair and how outcomes compare with infrarenal EVAR remains unclear. This study examined perioperative outcomes of patients undergoing complex EVAR, focusing on differences with complex open repair and standard infrarenal EVAR.

Characterization of endoleak following endovascular repair of abdominal aortic aneurysms

Aneurysm models have been developed to study the pathobiology of abdominal aortic aneurysm and to evaluate the efficacy of endovascular therapy. The purpose of this review is to describe the use and limitations of current animal and experimental models for the characterization of endoleak following endovascular repair of abdominal aortic aneurysms.     

Impact of endovascular repair for abdominal aortic aneurysms in octogenarians

A total of 50 consecutive patients (86% male; median age, 82 years) underwent endovascular repair of abdominal aortic aneurysms (AAAs) ranging from 4.0 to 9.0 cm (median, 5.2 cm). Efficacy of aneurysm exclusion was assessed by angiography, duplex scan, and/or contrast-enhanced computed tomography (CT). Acute technical success was 82%. Access failed in one patient, and immediate conversion to open operation was required in two patients. Improper deployment of the endoluminal graft (ELG) across the renal arteries occurred in one patient. The median operation time, estimated blood loss, packed red blood cells received, contrast volume, and length of intensive care and hospital stay were 128 min, 200 mL, 0.1 unit, 297 mL, 0.9 days, and 3 days, respectively. ELG limb thrombosis was seen in one patient. There were 4 (8%) early endoleaks, and 2 endoleaks were discovered in other patients at 3 and 6 months. Local/vascular and remote/systemic postoperative complications were seen in 13 (26%) and 9 (18%) patients, respectively. At a median follow-up of 11 months (range 2 to 36 months), clinical success was 78%. The aneurysm sac diameter (n = 49) decreased from a preoperative median of 5.2 to 4.7 cm (p = 0.0001). Technical success was high, and results at 11 months were satisfactory. Long-term outcomes require further study.     

Anatomic suitability of ruptured abdominal aortic aneurysms for endovascular repair

Mortality from ruptured abdominal aortic aneurysms (rAAAs) remains high despite improvements in anesthesia, postoperative intensive care, and surgical techniques. Recent small series and single-center experiences suggest that endovascular aneurysm repair (EVAR) for rAAAs is feasible and may improve short-term survival. However, the applicability of EVAR to all cases of rAAA is unknown. The purpose of this study was to investigate the anatomical suitability of ruptured aneurysms for EVAR as determined by preoperative cross-sectional imaging. A contemporary consecutive series of rAAAs presenting to a tertiary academic center was retrospectively reviewed. Preoperative radiographic imaging was reviewed and assessed for endovascular compatibility based on currently available EVAR devices. Patients with aneurysm morphology demonstrating neck diameter >32 mm, neck length <10 mm, neck angulation >60 degrees, severe iliac tortuosity, or external iliac diameter <6 mm were deemed noncandidates for EVAR. Forty-seven rAAAs were treated over a 10-year period, with 47% of patients presenting with free rupture and 60% of patients transferred from outside hospitals. Five (11%) patients were treated with EVAR, all over the past 2 years, while the remaining 42 patients underwent open repair. Preoperative imaging was available for review in 43 (91%) patients, and morphological measurements indicated that 49% would have been candidates for EVAR with currently available devices. Criteria precluding EVAR in this cohort were inadequate neck length in 73%, unsuitable iliac access in 23%, large neck diameter in 18%, and severe neck angulation in 14%. Overall 30-day mortality was 34%, and 1-year mortality was 42%. Candidates for EVAR were more likely than non-EVAR candidates to be male (95% vs. 68%, p = 0.046) and to have smaller sac diameters (7.0 vs. 8.5 cm, p = 0.02) and longer neck lengths (24.1 vs. 8.6 mm, p < 0.0001); less likely to have a >60 degree angulated neck (10% vs. 45%, p = 0.0002), larger external iliac diameter (8.9 vs. 7.3 mm, p = 0.015), and less blood loss during surgical repair (2.4 vs. 6.0 L, p = 0.02); and more likely to be discharged home (71% vs. 25%, p = 0.05). There were no differences in 30-day, 1-year, or overall mortality between candidates for EVAR and noncandidates. Only 49% of patients with rAAAs in this consecutive series were found to be candidates for EVAR with conventional stent-graft devices. Differences in demographics, aneurysm morphology, and outcomes between candidates and noncandidates undergoing open repair suggest that differential risks apply to ruptured aneurysm patients. Protocols and future reports of EVAR for rAAAs should be tailored to these results. Device and technique modifications are necessary to increase the applicability of EVAR for rAAAs.     

Continued expansion of aortic necks after endovascular repair of abdominal aortic aneurysms

Background: Longitudinal studies have revealed that the aortic segment proximal to an infrarenal abdominal aortic aneurysm (AAA) is at risk for continued enlargement after a standard aneurysm repair. Similarly, preliminary reports have shown expansion of one or both aortic necks after endovascular repair. Although some investigators have suggested that this may be a transient effect, continued dilatation at the endograft attachment site could effect the overall device stability. Methods: As part of a multi-institutional trial of endovascular grafting for the treatment of AAA, 59 patients were successfully implanted with straight endografts between February 1993 and January 1995. A morphometric analysis of aortic neck size was undertaken with serial review of computed tomography scans available through April 1997. The neck sizes at both graft attachment sites were measured, with investigators blinded to patient identity and date of scan. Changes in minor diameter were defined, annual interval expansion rates were calculated, and the data were correlated with endoleak, device migration, aneurysm size change, endograft diameter, attachment system fractures, and initial preimplant neck size. Results: Significant aortic neck enlargement, particularly at the level of the distal neck, was observed for at least 24 months after AAA repair. The annual interval dilation rates of the proximal aortic neck were 0.7 ± 2.1 mm/y (P = .023) and 0.9 ± 1.9 (P = .008) mm/yr during the first and second years, respectively. Enlargement of the distal neck during the observation period was more marked, with corresponding annual expansion rates of 1.7 ± 2.9 mm/y (P < .001) and 1.9 ± 2.5 (P < .001) mm/year. In 5 patients (14%), the minor diameter of the distal neck was at least 6 mm larger than the preimplant diameter of the graft. Migration of the distal attachment system was observed in 3 of these 5 patients. Expansion rates did not have a statistically significant correlation with initial neck size, endograft dimensions, aneurysm size change, presence of endoleak, or attachment system fracture. Conclusions: Aortic neck enlargement was observed for at least 2 years after endovascular grafting. Close patient follow-up remains mandatory in lieu of the potential risk of late failure as a result of continued aortic expansion. The relative contribution of device design to this phenomenon will need to be defined. (J Vasc Surg 1998;28:422-31.)     

Maximal aortic diameter affects outcome after endovascular repair of abdominal aortic aneurysms

Objective

The purpose of this study was to evaluate whether maximal aortic diameter affects outcome after endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm (AAA).