Blayne A. Roeder

Global experience with an inner branched arch endograft.

BACKGROUND Branched endografts are a new option to treat arch aneurysm in high-risk patients. METHODS AND RESULTS We performed a retrospective multicenter analysis of all patients with arch aneurysms treated with a new branched endograft designed with 2 inner branches to perfuse the supra aortic trunks. Thirty-eight patients were included. The median age was 71 years (range, 64-74 years). An American Society of Anesthesiologists score of 3 or 4 was reported in 89.5% (95% confidence interval [CI], 79.7-99.3) of patients. The 30-day mortality rate was 13.2% (95% CI, 2.2-24.2). Technical success was obtained in 32 patients (84.2% [95% CI, 72.4-95.9]). Early secondary procedures were performed in 4 patients (10.5% [95% CI, 0.7-20.3]). Early cerebrovascular complications were diagnosed in 6 patients (15.8% [95% CI, 4.0-27.6]), including 4 transient ischemic attacks, 1 stroke, and 1 subarachnoid hemorrhage. The median follow-up was 12 months (range, 6-12 months). During follow-up, no aneurysm-related death was detected. Secondary procedures during follow-up were performed in 3 patients (9.1% [95% CI, 0.0-19.1]), including 1 conversion to open surgery. We compared the first 10 patients (early experience group) with the subsequent 28 patients. Intraoperative complications and secondary procedures were significantly higher in the early experience group. Although not statistically significant, the early mortality was higher in the early experience group (30% [95% CI, 0.0-60.0]) versus the remainder (7.1% [95% CI, 0.0-16.9]; P=.066). Being part of the early experience group and ascending aortic diameter≥38 mm were found to be associated to higher rates of combined early mortality and neurologic complications. CONCLUSIONS Our preliminary study confirms the feasibility and safety of the endovascular repair of arch aneurysms in selected patients who may not have other conventional options. CLINICAL TRIAL REGISTRATION INFORMATION Thoracic IDE NCT00583817, FDA IDE# 000101.

Total Endovascular Treatment of Aortic Arch Disease Using an Arch Endograft With 3 Inner Branches

Purpose: To report early experience with a new endovascular graft developed for aortic arch aneurysm repair in patients unfit for open surgery. Case Report: Three consecutive men (62, 74, and 69 years old) at high risk for open repair were treated for postdissection aortic arch aneurysms using a custom-made 3 inner branched endovascular graft. The 2 proximal branches are antegrade and perfuse the innominate artery and the left common carotid artery; the third branch is retrograde and perfuses the left subclavian artery. The latter is preloaded with a catheter and wire to aid cannulation. Technical success was achieved in each case. The mean procedure time, fluoroscopy duration, and contrast volume were 180 minutes, 35 minutes, and 145 mL, respectively. The perioperative period was uneventful. All branches were patent on 6-month computed tomography and duplex ultrasound imaging. Conclusion: This new patient-specific device allows total endovascular revascularization of the supra-aortic trunks during arch repair. These encouraging results support its more widespread use.

Endovascular Repair of Saccular Ascending Aortic Aneurysm After Orthotopic Heart Transplantation Using an Investigational Zenith Ascend Stent-Graft:

Purpose: To report the use of an investigational stent-graft to treat an ascending aortic aneurysm in a patient with a heart transplant. Case Report: A 48-year-old man presented with a 3.5×1.5-cm saccular aneurysm in the mid anterior ascending aorta, abutting the sternum. The patient’s history was notable for placement of a left ventricular assist device followed by orthotopic heart transplantation 2 years prior to treat end-stage familial dilated cardiomyopathy. Under compassionate use, a custom-designed ascending aortic stent-graft (Zenith Ascend) was successfully delivered via an 18-F system and deployed just distal to the origin of the left main coronary artery under pulmonary artery catheter–guided rapid ventricular pacing. The patient was discharged the next day, and 6-month follow-up was unremarkable. Imaging at 5 months showed an excluded aneurysm sac with no endoleak or migration. Conclusion: The ideal ascending aortic stent-graft should be low profile, conformable to the arch anatomy, with short tip delivery system and a stepwise deployment mechanism that allows precise placement relative to the ostia of the coronary arteries and the innominate artery. This case illustrates the advancement of endovascular techniques to the most challenging segment of the aorta to decrease morbidity and mortality in high-risk patients.

Early experience with a modified preloaded system for fenestrated endovascular aortic repair

Objective: Preloaded endovascular delivery systems expand the anatomic eligibility for complex aortic repair by requiring only one iliac access vessel and providing a stable platform for guiding sheaths into challenging target vessels. This article reports the lessons learned and early clinical outcomes using a modified preloaded delivery system for fenestrated endovascular aneurysm repair (FEVAR) in three aortic centers in Europe. Methods: From October 2015 to March 2016, consecutive patients presenting with extensive aortic aneurysm treated with a modified preloaded FEVAR were prospectively enrolled from three high volume European aortic centers. The new design is a modification of previous designs of preloaded fenestrated stent grafts and of the p‐branch device platform. The technical details of implantation are described and perioperative outcomes, including the learning curve, are collected and reported. Results: All patients (30 patients; 80% men; 70.2 years old) presented for nonurgent repair of either a type Ia endoleak (3/30; 10%), a type I‐II‐III thoracoabdominal (8/30; 27%), or a type IV thoracoabdominal or pararenal (19/30; 63.%) aneurysm repair of a mean size of 64 ± 13 mm using a custom made device. Primary technical success was achieved in 28 of 30 patients (93%) and assisted primary technical success in 29 of 30 patients (97%). The two technical failures included open conversion to repair a ruptured iliac artery and restenting of a dissected superior mesenteric artery which was recognized hours after the index procedure had finished. The mean procedure time was 277 ± 153 minutes, fluoroscopy time 79 ± 36 minutes, dose area product 112 ± 90 Gy cm2, and contrast volume 87 ± 46 mL. All renal fenestrations were successfully stented without type III endoleak on completion angiogram; the preloaded guiding sheaths were used for 53 of 58 renal arteries (91%). Challenges related to learning to the use of the modified preloaded system were experienced early and had no clinical consequences. Major complications occurred in seven cases (23%), including two perioperative deaths because of stroke and sepsis following primary conversion attributable to iliac rupture. There were no target vessel occlusions or type I/III endoleaks found on postoperative imaging. Conclusions: Based on early experience, the modified preloaded system can be safely and effectively used during FEVAR, with good technical result and a short period of learning. This device expands treatment to patients with compromised iliac access, thus, additional patients and more follow‐up will be required to determine unique risks of operating in this patient population.

Validated Computational Model to Compute Re-apposition Pressures for Treating Type-B Aortic Dissections

The use of endovascular treatment in the thoracic aorta has revolutionized the clinical approach for treating Stanford type B aortic dissection. The endograft procedure is a minimally invasive alternative to traditional surgery for the management of complicated type-B patients. The endograft is first deployed to exclude the proximal entry tear to redirect blood flow toward the true lumen and then a stent graft is used to push the intimal flap against the false lumen (FL) wall such that the aorta is reconstituted by sealing the FL. Although endovascular treatment has reduced the mortality rate in patients compared to those undergoing surgical repair, more than 30% of patients who were initially successfully treated require a new endovascular or surgical intervention in the aortic segments distal to the endograft. One reason for failure of the repair is persistent FL perfusion from distal entry tears. This creates a patent FL channel which can be associated with FL growth. Thus, it is necessary to develop stents that can promote full re-apposition of the flap leading to complete closure of the FL. In the current study, we determine the radial pressures required to re-appose the mid and distal ends of a dissected porcine thoracic aorta using a balloon catheter under static inflation pressure. The same analysis is simulated using finite element analysis (FEA) models by incorporating the hyperelastic properties of porcine aortic tissues. It is shown that the FEA models capture the change in the radial pressures required to re-appose the intimal flap as a function of pressure. The predictions from the simulation models match closely the results from the bench experiments. The use of validated computational models can support development of better stents by calculating the proper radial pressures required for complete re-apposition of the intimal flap.

Historical Aspects and Evolution of Fenestrated and Branched Technology

To provide a durable repair over the life of the patient, an endovascular aneurysm repair must seal in healthy aorta. As a result, many aneurysm patients are not suitable candidates for standard infrarenal or thoracic endovascular grafts. To treat the patients, a group of innovators focused on incorporating branches into endovascular repair in order to achieve seal zones in healthy aorta. This chapter details the development of fenestrated and branched endografts from the first prototypes and clinical cases with simple fenestrated grafts in the late 1990s to the most recent developments where patients can be offered the possibility of endovascular treatment of the entire aorta from the sino-tubular junction to the internal and external iliacs. Specifically, we discuss devices developed to treat short neck abdominal aortic aneurysms (AAAs), juxtarenal or pararenal AAAs, iliac aneurysms, complex thoracoabdominal aneurysms, and aortic arch. A global, collaborative, multidisciplinary team was required to translate ideas, philosophies, and technologies into viable new devices and therapies for patients. In addition to physicians from multiple specialties, the team included innovative engineers and technicians who applied their skills in prototype manufacture development and testing. Fenestrated and branched stent-graft technology is based on a common set of fundamental principles: achieving seal in healthy aorta, matching the native anatomy whenever possible, and optimizing the endovascular repair for long-term durability. These philosophies have been validated through publications of single-center experience, prospective single-center trials, and multicenter prospective trials.

Commentary: Proximal Uncovered Stent Disconnections With the Standard and Low-Profile Zenith AAA Stent-Grafts

In this issue of the JEVT, Torres-Blanco and colleagues and Lindstrom and colleagues alert us to the disconnection of the proximal suprarenal uncovered stent in the Zenith abdominal aortic aneurysm (AAA) stent-grafts (Cook Medical, Bloomington, IN, USA). Disconnections of the proximal uncovered stent are indeed infrequent but were noted with the first generation of the stent prior to 2002. At that time, the device was modified with double suture reinforcement to secure the uncovered stent. Since this modification was introduced, the problem of uncovered stent disconnection has become very rare. Failure of aortic stent-grafts is most often multifactorial (Figure 1). Although there is usually a leading cause, stentgraft failure is often due to overlapping factors. These can be grouped in 3 categories: patient (eg, poor anatomy or progression of aortic disease), physician (eg, selection of improper treatment, faulty or inaccurate deployment or device selection), and device factors (eg, integrity or design issues). The proximal suprarenal stent was designed to optimize seal by adding fixation to the aorta to stop migration. The problem highlighted in this issue of the JEVT reflects a device integrity issue, ultimately disconnection of the uncovered stent. An aortic stent-graft is subjected to longterm cyclic forces acting to displace the stent-graft. Moreover, these forces must be overcome in the setting of continual changes in aortic neck configuration. Albeit rare, this structural failure highlights the importance of continued lifelong surveillance of endografts, regardless of specific type or manufacturer. It is critical that we analyze device successes or failures in the context of the specific anatomic conditions for which the devices are approved. The Cook Zenith AAA stent-graft was tested clinically and approved for use in normal aortic segments of at least 15-mm length with <60° angulation. Although these requirements represent ideal conditions, numerous reports indicate that technical and clinical success can sometimes be achieved outside these strict anatomic recommendations. It is important to note that prospective trials of AAA devices to support Food and Drug Administration (FDA) approval include only patients treated within the instructions for use (IFU). These patients are followed for 5 years. There is a paucity of prospective clinical data on outside IFU use of any AAA device. Use of any AAA device outside the IFU should be undertaken with extreme caution. 636029 JETXXX10.1177/1526602816636029Journal of Endovascular TherapyOderich and Roeder research-article2016

The Cook Zenith Devices

The Cook Zenith family of devices includes a wide range of custom and off-the-shelf endovascular grafts and devices capable of treating patients with complex anatomy and pathology, including those previously considered unsuitable for endovascular repair. Available devices include the Zenith AAA, Zenith TX2 TAA, Zenith Fenestrated Graft, Iliac Branch Graft, and Helical Branch Graft, and the Zenith Dissection Stent. In addition, low-profile versions of the AAA (abdominal aortic aneurysm) and TAA (thoracic aortic aneurysm) grafts (designed based on a combination of nitinol stent technology and thin-wall graft material) are now available as investigational devices, allowing for endovascular treatment of patients with smaller access vessels. This chapter includes a review of device evolution and a brief review of the literature, which indicates that all commercially available devices are associated with positive clinical outcomes.