The CX Aortic Edited Cases session yesterday provided the unique opportunity for the audience to interact with experts and ask questions about the cases being presented. The first session focused on thoracic aortic cases and the remainder were abdominal aortic cases.
Michael Dake (Stanford, USA) presented a case with the TAG thoracic branch endoprosthesis (Gore) which is part of a US feasibility multicentre trial that has evaluated 22 patients (mean age 74.1±10.5 years, 54.5% male) undergoing branched thoracic endovascular aortic repair (B-TEVAR) in Ishimaru zone 2.
According to Dake, the endograft features a single side branch designed to facilitate aortic coverage proximal to the left subclavian artery, while maintaining branch vessel patency. Pathology treated included fusiform (n=10) or saccular (n=12) aneurysm, with a mean aortic diameter of 5.7±1.1cm.
Reporting on the progress of the trial, he said that the primary endpoints of device delivery and branch vessel patency was achieved in 100% of patients, without 30-day deaths, stroke or permanent paraplegia. Median duration of hospitalisation was four days. Type I endoleaks at completion angiography were observed in four patients, and all resolved by one month without reintervention. All side branches were patent at one month. Kaplan-Meier survival at six months was 94.7%. Presenting his edited case, Dake maintained that in his experience “total endovascular repair of distal zone 2 arch aortic aneurysms can be safely achieved with a novel branched arch endograft. Future studies will evaluate the feasibility of this approach for aneurysms encompassing the brachiocephalic trunk and left carotid artery”.
The second thoracic case, presented by Jos van den Berg (Lugano, Switzerland), featured a thoracic proximal scallop stent graft (Relay, Bolton Medical) for expanding proximal neck in patients with challenging anatomy. Van den Berg pointed out that one of the problems with TEVAR is the extension of the disease close to the left subclavian artery (LSA). He said that standard thoracic endografts can be used in these cases, but will imply coverage of the LSA.
“Covering of the LSA may remain without clinical sequelae, but most operators prefer to perform a left common carotid-subclavian artery bypass in order to guarantee antegrade flow in the left vertebral artery. Although feasible, an additional bypass procedure carries an additional risk of morbidity. Off-the-shelf solutions are currently not available, although several groups have demonstrated the feasibility and safety of in-situ fenestration (this is still considered an off-label use though). In some instances in situ fenestration is not an option,” he explained.
The case he presented was an 81-year-old patient with a penetrating ulcer of the proximal descending thoracic aorta (“blister-like”), close to the origin of the LSA. The complicating factor in the case was the presence of a left vertebral artery (LVA) that originated directly from the aortic arch. Maintaining that the options to treat this particular anatomy are limited, van den Berg said he opted for a solution that used a custom-made stent graft with a proximal scallop (proximal scalloped gate on main body).
“The advantage of the system is the fact that it has a nitinol pre-curved inner catheter that allows tracking to the natural curvature of the aorta. The pre-curve enhances the alignment of the S-Bar, orientates the scallop and provides pushability. Together with the flexible inner sheath of the delivery system it allows for atraumatic advancement of the graft and better control because of the staged graft expansion. In this case the self-alignment after insertion was optimal, and no further adjustments of the position of the scallop were necessary. Control angiography demonstrated patency of both the LVA and LSA, and control CT angiography at one month showed proper positioning of the scallop, and patency of all supra-aortic vessels,” van den Berg reported. He added, “This case clearly demonstrated the advantages of custom-made stent grafts for patients with non-standard anatomy.”
“I think this case has shown that we should be thinking of this option, particularly in localised disease that is not involving the outer curve of the aortic arch,” Holden summed up.
For the final thoracic aortic case Eric Verhoeven (Nuremberg, Germany) demonstrated the use of the Zenith Alpha thoracic graft (Cook Medical) in treating a thoracic aneurysm with a modular system. He reported that the new generation system has retained the familiar attributes of the earlier Zenith grafts which include a specifically designed proximal and distal graft. “This allows the operator to concentrate on one landing zone at the time. Probably the most important feature is that the distal graft provides a distal bare stent with reverse hooks that act effectively against upwards migration which has been seen in many other devices,” Verhoeven explained.
In his case presentation, he demonstrated the use of the new deployment system which he says enables “very accurate and stress-free deployment. The deployment forces needed are highly reduced thanks to a captor sleeve, and the opening of the top bare stent is achieved by a simple and smooth rotational movement of the handle”.
The audience interaction notably touched on some difficulties experienced with distal deployment of the device, to which Verhoeven advised, “I think it is mandatory in that instance not only to remain calm, and to go through the steps, but also not to move the graft, because if you move the graft in any way, especially up, then you can encounter a problem. I am teaching my people to keep their hand stable.”
Following the thoracic cases, the session turned to the presentation of abdominal aortic cases. Konstantinos Donas (Münster, Germany) presented a case demonstrating chimney EVAR for the treatment for type Ia endoleak with the Endurant II (Medtronic) and the V12 (Maquet Getinge).
He explained that endovascular repair of type Ia endoleaks comes with several anatomical challenges. The majority of patients suffer from large aneurysms (>6cm diameter), often in combination with abdominal symptoms or rupture needing urgent treatment. Migration of the graft can partially occlude the origin of the renal arteries due to the struts of the suprarenal bare metal stent.
“Deployment of flexible stent grafts and subsequently of the chimney graft creates a new adequate neck and sealing zone excluding sufficiently the type Ia endoleak with off-the-shelf devices. The devices fit the often severely angulated neck which is responsible for the migration of the previously deployed endoprostheses showing excellent comformability. Additionally, the downward orientation of the renal arteries facilitates an easier cannulation and placement of the sheaths in the involved renal arteries from the upper extremity,” Donas told the audience, adding that the chimney technique in his experience “has clear clinical and technical advantages for the management of type Ia endoleaks”.
William Jordan (Atlanta, USA) showed a case of an 84-year-old male patient with an abdominal aortic aneurysm who had typical comorbidities of coronary artery disease including prior coronary bypass. The patient was treated with EndoAnchors (Medtronic).
“Considering his anatomic configuration and other medical comorbidities, we used the prophylactic anchors to improve seal and fixation in the infrarenal position. A 32mm Endurant IIS graft (Medtronic) was used with bilateral 16 x 13 x 124 iliac limbs. After the graft was deployed, we performed a balloon angioplasty and then used four prophylactic anchors prior to angiography. The completion angiogram showed excellent fixation just below the pre-existing right renal stent with only a faint type IV endoleak. The patient recovered well and his CT scan is planned at a later setting,” Jordan reported.
He explained to the audience that EndoAnchors can facilitate the treatment of short neck aneurysms, can treat acute type I endoleaks with directed fixation at the site of the endoleak, and finally, are an important adjunct to the endovascular armamentarium.
Later in the session Holden demonstrated Endovascular Aneurysm Sealing (EVAS) with the Nellix Generation 3.5 (Endologix).Speaking of the new generation device, Holden noted that the most important improvement is secure distal attachment of the endobag onto the bottom stent element, resulting in predictable, precise distal seal. “This enables Nellix to successfully manage a number of challenging iliac artery anatomies, especially concomitant or isolated common iliac artery aneurysms. With this device, the entire iliac artery aneurysm can be treated with preservation of the internal iliac artery. Patients with short common iliac arteries can also be successfully treated with internal iliac artery preservation,” Holden said.
The final case of the day demonstrated the use of the Onyx liquid embolisation system (Medtronic) for the treatment of type II endoleaks after EVAR. Arne Schwindt’s (Münster, Germany) case showed the rare situation of an aberrant splenic artery emerging separately from the coeliac trunk directly from the aorta. After fenestrated EVAR the aberrant splenic artery formed a type II endoleak pressurising the aneurysmal sac and led to aneurysmal growth.
Concerning the embolisation technique Schwindt stressed the importance of injecting the Onyx in a slow and controlled way to avoid polymer displacement and gave the tip to reduce the fluoroscopic frame rate during embolisation in order to reduce X-ray exposure to the patient and the interventionalist. Schwindt concluded that with rising numbers of EVAR, the number of type II endoleaks requiring treatment will rise as well and that even new technologies like EVAS are not free of endoleak that lead to aneurysm expansion. Finally, he advised that follow up and treatment algorithms for persisting type II endoleaks are mandatory to identify those patients requiring intervention.
The Aortic Edited Cases also featured a case showing the deployment of the INCRAFT device (Cordis), the Zenith Alpha abdominal graft (Cook Medical), and the Excluder iliac branch endoprosthesis (Gore). There was also a case demonstrating infection control with open repair post-EVAR using the Intergard Synergy (Maquet Getinge).
