Current Status of Branched Stent-Graft Technology in Treatment of Thoracoabdominal Aneurysms

Isolated Common Iliac Artery Aneurysms Treated Solely With Iliac Branch Stent-Grafts: Midterm Results of a Multicenter Registry

PURPOSE

To assess early and midterm outcomes of iliac branch device (IBD) implantation without an aortic stent-graft for the treatment of isolated common iliac artery aneurysm (CIAA).

METHODS

From December 2006 to June 2016, 49 isolated CIAAs in 46 patients were treated solely with an IBD at 7 vascular centers. Five patients were lost to follow-up, leaving 41 male patients (mean age 72.5±7.8 years) for analysis. Mean CIAA diameter was 39.1±10.5 mm (range 25-65). Thirty-two patients (2 with bilateral CIAAs) were treated with a Cook Zenith iliac branch device; 9 patients (1 bilateral) received a Gore Excluder iliac branch endoprosthesis. Primary endpoints were technical success, survival, aneurysm exclusion, device patency, and freedom from reintervention at 1 and 5 years. Freedom from major adverse events and aneurysm shrinkage at 1 year were also assessed.

RESULTS

Thirty-day mortality and the IBD occlusion rate were 2.4% and 2.3%, respectively. At a mean follow-up of 40.2±33.9 months, no patient presented buttock claudication, erectile dysfunction, or bowel or spinal cord ischemia. Three patients died within 6 months after the procedure. Estimates of cumulative survival, device patency, and freedom from reintervention were 90.2%, 95.2%, and 95.7%, respectively, at 1 and 5 years. At 1 year, CIAA shrinkage ≥5 mm was recorded in 21 of 38 survivors. No evidence of endoleak, device migration, or disconnection was found on imaging follow-up.

CONCLUSION

The use of IBDs without an aortic stent-graft for isolated CIAAs resulted in excellent patency, with low morbidity and mortality. This, in conjunction with no endoleak or migration and a low reintervention rate, supports the use of isolated IBDs as a stable and durable means of endovascular reconstruction in cases with suitable anatomy. Longer follow-up and a larger cohort are needed to validate these results.

Type II endoleak after endoluminal repair of thoracic aortic aneurysm associated with native coarctation

Aneurysm formation and recurrent coarctation are common complications of coarctation repair, and various types of treatment have been described. Native aortic coarctation during adult life is rarer and can be responsible for severe complications. We report an original case of thoracic aortic aneurysm associated with native coarctation successfully treated by a hybrid approach, comprising retrograde implantation of a thoracic stent graft and carotid-axillary bypass graft. A large intercostal collateral was embolized with coils.

In Vivo Antegrade Fenestration of Abdominal Aortic Stent-Grafts

Purpose:

To examine in a canine model the feasibility of antegrade fenestration of abdominal aortic stent-grafts to preserve the patency of the renal arteries.

Methods:

Two large dogs underwent antegrade fenestration of stent-grafts in the perirenal aorta. Before fenestration, bare stents were inserted in both renal arteries as fluoroscopic landmarks. A 12-mm iliac extension served as the canine aortic endograft. The first procedure was done under ultrasound and fluoroscopic guidance, using an intravascular ultrasound (IVUS) probe inserted in the vena cava and a Pioneer IVUS catheter. The second was performed exclusively under fluoroscopic guidance with a Brockenbrough needle. Angiograms and duplex ultrasound were planned for 1 month, after which the dogs would be sacrificed for autopsy. The explanted endograft was subjected to biomaterials analysis, with a focus on fabric tear.

Results:

Perforation of the aortic graft and catheterization of the renal arteries with a floppy guidewire were possible in both animals. In dog 1, aortic graft dilation and subsequent fenestration were not possible, and the experiment was terminated. However, the procedure was successful in both renal arteries of dog 2. At 1-month follow-up in this dog, both renal arteries were patent. Stent fractures were observed bilaterally. There was no extension of the damage to the fabric beyond the area of fenestration.

Conclusion:

In vivo antegrade fenestration of aortic endografts is technically feasible. However, improvements in technique, instrumentation, and materials are required to make it a reliable and reproducible way of allowing stent-graft vascularization of aortic side branches.

Results of Thoracic Endovascular Grafting in Different Aortic Segments

Purpose:

To compare the results of thoracic endovascular grafting of different aortic segments performed with commercially available stent-grafts.

Methods:

Between January 1999 and October 2006, 178 patients (150 men; mean age 69.4±10.2 years) underwent endovascular grafting of the thoracic aorta (68 hybrid procedures) with commercially produced stent-grafts from 4 manufacturers. Patients were divided into 3 groups according to the aortic segment involved: 64 aortic arch cases (37 hybrids for supra-aortic trunks revascularization), 100 descending thoracic aorta (DTA) cases (17 hybrid: 12 for access and 5 for associated abdominal aortic aneurysm), and 14 thoracoabdominal aorta (TaA) patients excluded from conventional repair (14 hybrids for renal and splanchnic revascularization).

Results:

The technical success was 93.8% (167/178). Overall 30-day mortality was 5.6% (10/178). There were 10 (5.6%) type I endoleaks. Initial clinical success was 88.2% (157/178). At a mean follow-up of 29.3±21.2 months, the midterm clinical success was 89.9% (160/178). In the arch group, the technical success was 85.9% (55/64). Thirty-day mortality was 6.3% (4/64). There were 8 (12.5%) type I endoleaks. Initial and midterm clinical success rates were 79.7% (51/64) and 85.9% (55/64), respectively. In the 100-patient DTA group, the technical success was 98.0%. Thirty-day mortality was 2.0%. The type I endoleak rate was 2.0%. Clinical success was 96.0% initially and 95.0% at midterm. All 14 of the TaA cases were completed successfully, but 30-day mortality was 28.6% (4/14). There were no type I endoleaks. Clinical success rates initially and at midterm were both 71.4% (10/14).

Conclusion:

Over the last 6 years, synergy between endovascular and surgical procedures allowed treatment of all segments of the thoracic aorta. Overall perioperative and medium-term results were reasonably favorable; however, they were more satisfactory when the descending thoracic aorta alone was involved. Hybrid procedures allowed treatment of all aortic segments, but they decreased the success rates significantly. Endovascular grafting is currently our preferred method of treating pathologies involving the DTA and aortic arch, while our data suggest limiting the use of stent-grafts to high-risk patients or compassionate indications when the thoracoabdominal aorta is involved.

Association of red blood cell transfusion and postoperative outcomes after endovascular aortic repair

BACKGROUND

Several studies have documented worse postoperative outcomes in patients who received red blood cell (RBC) transfusion perioperatively during cardiac surgery or in critical care settings. These findings were attributed to activation of the inflammatory response with the release of cytokines and immune suppression. The aim of this study was to evaluate the association of RBC transfusion on the day of surgery and postoperative outcomes following endovascular aortic repair (EVAR).

METHODS

A total of 510 patients who underwent EVAR from April 2005 to March 2007 were considered for analysis. The exposure of interest was whether or not patients receive RBC transfusion on the day of surgery. The primary outcome was a composite in-hospital morbidity/mortality outcome. The authors assessed the association between RBC transfusion and our composite outcome using logistic regression after adjusting for the available potential confounders using propensity score matching.

RESULTS

Propensity scores were estimated for 418 out of the 510 patients; 92 patients were not included because of missing data. Propensity matching resulted in 42 successfully matched pairs. Median (quartiles) propensity score was 0.46 (0.28, 0.66) for the matched patients with transfusion and 0.46 (0.29, 0.61) for the matched patients without transfusion (P = .75, Wilcoxon rank sum test). Results of the multivariable model developed after propensity score matching suggest that RBC transfusion was not significantly associated with experiencing a postoperative complication; estimated odds ratio (95% confidence interval) of 2.7 (0.8, 9.0), P = .11.

CONCLUSION

In this study, RBC transfusion was not independently associated with an increased incidence of in-hospital morbidity and mortality after EVAR.

Use of covered stents and endograft as a rescue treatment in a patient with a complex form of recurrent aortic coarctation

We report our experience with one patient with recurrent coarctation and aneurysm degeneration treated endoluminally. A novel technique was used combining balloon-expandable with self-expandable endografts. The balloon-expandable component expanded the area of stenosis and also created a neck to allow the implantation of the self-expandable endograft to exclude the aneurysm. Mismatch of diameters was solved with the creation of a new proximal neck, in which the distal end was progressively expanded to reach the appropriate diameter to implant the self-expandable endograft inside. Expansion of the narrow stenosis and complete exclusion of the aneurysm was achieved without a residual pressure gradient.

Endovascular repair of a type III thoracoabdominal aortic aneurysm in a patient with occlusion of visceral arteries

The successful endovascular repair of a type III thoracoabdominal aortic aneurysm (TAAA) with the use of a tube endograft is reported. A 56-year-old male with a 6.4-cm type III TAAA, a 4.2-cm infrarenal abdominal aortic aneurysm, and chronic renal insufficiency presented with flank pain, nausea, acute anuria, and serum creatinine of 6.1 mg/dl. Acute occlusion of the left solitary renal artery was diagnosed and emergent recanalization with percutaneous transluminal angioplasty and stenting was performed successfully, with reversal of the serum creatinine level at 1.6 mg/dl. Further imaging studies for TAAA management revealed ostial occlusion of both the celiac artery (CA) and the superior mesenteric artery (SMA) but a hypertrophic inferior mesenteric artery (IMA) providing retrograde flow to the aforementioned vessels. This rare anatomic serendipity allowed us to repair the TAAA simply by using a two-component tube endograft without fenestrations (Zenith; William Cook, Bjaeverskov, Denmark) that covered the entire length of the aneurysm, including the CA and SMA origins, since a natural arterial bypass from the IMA to the CA and SMA already existed, affording protection from gastrointestinal ischemic complications. The patient had a fast and uneventful recovery and is currently doing well 6 months after the procedure. To our knowledge, this is the first report in the English literature of successful endovascular repair of a TAAA involving visceral arteries with the simple use of a tube endograft.

Clinical Experience with a Customized Fenestrated Endograft for Juxtarenal Abdominal Aortic Aneurysm Repair

Despite the numerous stent-graft devices available, unsuitable anatomy is still the greatest exclusion criterion for endovascular abdominal aortic aneurysm (AAA) repair (EVAR). The present report describes an on-site preprocedural customization of a conventional Zenith stent-graft device just before the endovascular procedure that includes the creation of fenestrations and scallops as necessary for the patient's anatomy. Three patients with difficult anatomy in whom conventional AAA repair posed a high degree of risk were treated with customization of the stent-graft device to fit disparate renal arteries. A single fenestration for the left renal artery was made in two cases, and a single scallop was made in the other case to accommodate the superior mesenteric artery. Gold beads were used to mark the location of the fenestration and scallop. The three cases were successfully performed without perceptible endoleaks in the follow-up period, which ranged from 4 to 14 months. No procedure-related complications were detected; however, pneumonia developed in one patient 3 weeks after EVAR. The initial results with this technique are encouraging, and the role of EVAR can be significantly increased with the use of this customization technique when the interventionalist does not have access to the commercially available devices or when the waiting time is too prolonged to accommodate the patient's clinical situation.