Physician Modification of a Custom-Made Fenestrated Endograft By Closure of a Fenestration With Bovine Patch

PURPOSE

Ruptured mycotic pararenal aortic aneurysms are rare and serious condition that requires prompt treatment. Open surgery with aortic resection and in-situ or extra-anatomic reconstruction is the standard treatment. The aim of this technical note is to report urgent endovascular treatment using a readily available custom-made device (created for another patient), with a back-table modification using pericardium patch and a new fenestration.

TECHNIQUE

In preoperative measurements on centerline-based workstation, aortic diameter in proximal and distal landing zone and target vessel position matched the measurements of graft plan of custom-made device (CMD) besides left renal artery. To address current patient`s anatomy, closure of the nonsuitable fenestration with pericardial patch and creation of new fenestration (1 cm above and 1:15 hours posterior to original fenestration) for the respective target vessel have been performed. Postoperative computed tomography angiography (CTA) scan showed complete exclusion of aneurysm, perfused target vessels, and no endoleak. Under resistance-based antibiotic therapy, the patient was asymptomatic and showed normal infection parameters in blood samples postoperatively.

CONCLUSION

In the hands of an experienced endovascular aortic surgeon modification of a custom-made device is a quick and feasible technique in this emergency situation. Long-term follow-up must confirm the durability and reliability of this new technique.

CLINICAL IMPACT

The described technique of modification of a custom-made endograft can provide an alternative endovascular treatment option for urgent complex abdominal aortic pathologies. Compared to the current available treatment modalities, like physician modified endografts, off-the-shelf branched devices, parallel grafts and in-situ fenestration, it can save considerable time and provides reasonable sealing in ruptured cases. The technique offers a valuable add-on to the armamentarium of experienced endovascular physicians.

Chimney endovascular aneurysm repair (ChEVAR) for hostile neck complex aneurysm

OBJECTIVE

Recent guidelines recognize the role of chimney endovascular aneurysm repair (ChEVAR) in the treatment of complex aortic disorders. The optimal configuration and number of visceral vessels that can be incorporated is still controversial. We aim to review outcomes from a multi-institutional decade-long experience with ChEVAR.

METHODS

Patients undergoing ChEVAR with multiple (≥2) chimney branches were selected from a prospectively maintained database at the two academic university hospitals. All patients were poorly suited for fenestrated or branched endograft repair (F/BEVAR) and deemed poor-risk for open surgery.

RESULTS

Forty-nine multiple ChEVAR were performed in 44 men and 5 women, with complete outcome data at a mean follow-up of 18 months. Overall, 2 patients died during follow-up (4%) with no aneurysm-related mortality and two ruptures after ChEVAR (4.1%) due to a type Ib endoleak from iliac limb pullout and persistent gutter-flow, both repaired with endovascular means. No stroke or spinal cord ischemia was noted during the follow-up period. Reintervention was undertaken in eight patients (16.3%) with five reinterventions for persistent gutter-flow and four chimney graft-associated. Three-vessel ChEVAR was performed in 16 patients, with two-vessel ChEVAR in 33 patients for a total of 114 chimney branches (mean 2.3 chimneys per patient). There were 21 superior mesenteric artery (SMA), 45 right renal, 46 left renal artery (LRA), and two accessory LRA chimneys placed. Antegrade configuration of chimney branches was chosen in 43 patients (88%). There were no significant differences between three-vessel and two-vessel ChEVAR upon univariate analysis in aneurysm size (65.6 vs 60.5 mm; p = 0.059), iliac diameter (7.3 vs 7.1 mm; p = 0.85), or endograft oversizing (30 vs 32.5%; p = 0.43). Three-vessel ChEVAR was associated with a larger aneurysm neck diameter (28.4 vs 25.0 mm; p = 0.021), shorter native infrarenal neck (0.5 vs 3.37 mm; p = 0.002) as well as longer seal zone (36.33 vs 22.67 mm; p = 0.005) compared with two-vessel ChEVAR. At follow-up, there were no significant differences in gutter area between three-vessel and two-vessel ChEVAR (18.9 vs 15.7 mm³; p = 0.73) nor the rate of persistent gutter-flow (12.5 vs 9.1%; p = 0.71).

CONCLUSION

Reintervention to multiple chimney grafts and for persistent gutter-flow is higher compared to single chimneys and demands close surveillance. However, based upon this combined transantlantic experience, we believe multiple ChEVAR provides a reasonable and safe option for complex aortic aneurysm repair when open or custom endografts are not available or indicated based on their Instructions For use, even when triple chimney grafts are required. The optimal configuration for multiple ChEVAR still warrants further study, although theoretical preliminary advantages may exist for a combination of antegrade and retrograde chimneys.

Single institute experience of bypass surgery for complex anterior cerebral artery aneurysms: paying special attention to the spatial and diameter relationship between the efferent arteries

Single institute experience with bypass surgery of complex ACA aneurysm was retrospectively reviewed over a 6-year period. Eight patients with complex ACA aneurysms were treated with bypass, including five females and three males, with mean age of 34.2 years old. There were three pre-communicating aneurysms, one communicating artery aneurysm, and four post-communicating aneurysms (two in A2 and two in A3). A3-A3 side-to-side in situ bypass was applied in six cases. A3-radial artery-A3 interpositional bypass was used in one case with far apart A3s, and A3-A3 transplantation in the other with unparalleled aligned A3s. Three aneurysms were secured with proximal clipping, one with distal clipping, one with direct clipping, one with isolation, and two with embolization. Aneurysm obliteration was achieved in all cases. Only one in situ bypass from smaller donor artery towards larger recipient artery failed with minor postoperative infarction. Intraoperative bleeding from the site of anastomosis occurred in one case during embolization. All the patients showed complete recovery with normal neurological function during follow-up at out-of-patient clinics. A simplified surgical algorithm for complex ACA aneurysm is established based on the geometrical and spatial relationship between efferent arteries. The reasons of bypass failure and hemorrhagic complication are also discussed.

Flow Diversion for Intracranial Aneurysms Beyond the Circle of Willis

Background: Few reports have shown the therapeutic outcomes of flow diversion (FD) for intracranial aneurysms beyond the circle of Willis, and the efficacy of this technique remains unclear. Materials and methods: A retrospective study was performed on 22 consecutive patients, diagnosed with intracranial aneurysms beyond the circle of Willis, and treated with pipeline embolization device (PED) (Medtronic, Irvine, California, USA) between January 2015 and December 2019. Result: The 22 patients were between 16 and 66 years old (mean 44.5 ± 12.7 years), and six patients were male (27.3%, 6/22). Twenty-two patients had 23 aneurysms. The 23 aneurysms were 3-25 mm in diameter (12.2 ± 7.1 mm on average). The diameter of the parent artery was 1.3-3.0 mm (2.0 ± 0.6 mm on average). The 23 aneurysms were located as follows: 17 (73.9%, 17/23) were in the anterior circulation, and 6 (26.1%, 6/23) were in the posterior circulation. PED deployment was technically successful in all cases. Two overlapping PEDs were used to cover the aneurysm neck in 3 cases. One PED was used to overlap the two tandem P1 and P2 aneurysms. Other cases were treated with single PED. Coil assistance was used to treat 7 aneurysms, including 4 recurrent aneurysms and 3 new cases requiring coiling assistance during PED deployment. There were no cases of complications during PED deployment. All patients were available at the follow-up (mean, 10.9 ± 11.4 months). All patients presented with a modified Rankin Score (mRS) of 0. During angiographic follow-up, complete embolization was observed in 22 aneurysms in 21 patients, and one patient had subtotal embolization with the prolongation of stasis in the arterial phase. Conclusion: PED deployment for intracranial aneurysms beyond the circle of Willis is feasible and effective, with high rates of aneurysm occlusion.

Short-term outcomes of inner branches for endovascular repair of complex abdominal and thoracoabdominal aortic aneurysms

OBJECTIVES

To report our early experience using endografts with inner branches for the treatment of complex abdominal aortic aneurysms and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

A retrospective analysis of all patients treated in our institution for complex abdominal aortic aneurysms and TAAAs with custom-made stent grafts consisting of one or more inner branches. Data collected included patients demographics, aortic aneurysm morphology, stent grafts features, perioperative morbidity and mortality and short-term reintervention and mortality rates.

RESULTS

Twenty-seven patients (18 males, mean age 70 ± 7.1) were included. Indications for surgery included TAAAs (12, 41%) juxtarenal abdominal aortic aneurysms (10, 37%), type 1A endoleaks (4, 15%) and paraanastamotic aneurysms (1, 4%). A total of 90 inner branches were used. Twenty-one (78%) of the stent grafts consisted only of inner branches and six (22%) had a combination of inner branches with either fenestrations or outer branches. Technical success was achieved in 26/27 (96%) of the patients. There was one perioperative mortality. Six patients suffered from major perioperative adverse events. Mean follow-up was seven months (range 1-23). During the follow-up period, four patients (15%) required reinterventions. Branch-related reinterventions were performed in two (7%) patients. No occlusions of inner branches occurred during the follow-up.

CONCLUSIONS

Inner branches in branched endovascular aneurysm repairs offer a feasible option for the treatment of complex abdominal aortic aneurysms and TAAAs. The procedures can be completed with high technical success and with acceptable short-term branch-related reintervention rates. Further follow-up is required to determine the long-term durability of this technology.

Hybrid approach with endovascular and open surgical techniques for challenging aneurysms

This study is a case series describing the management of complex aneurysmal disease using the principles of both open and endovascular techniques.

Rationale for graft selection in patients with complex internal carotid artery aneurysms treated with extracranial to intracranial high-flow bypass and therapeutic internal carotid artery occlusion

OBJECTIVE After internal carotid artery (ICA) sacrifice without revascularization for complex aneurysms, ischemic complications can occur. In addition, hemodynamic alterations in the circle of Willis create conditions conducive to the formation of de novo aneurysms or the enlargement of existing untreated aneurysms. Therefore, the revascularization technique remains indispensable. Because vessel sizes and the development of collateral circulation are different in each patient, the ideal graft size to prevent low flow-related ischemic complications (LRICs) in external carotid artery (ECA)-middle cerebral artery (MCA) bypass with therapeutic ICA occlusion (ICAO) has not been well established. Authors of this study hypothesized that the adequate graft size could be calculated from the size of the sacrificed ICA and the values of MCA pressure (MCAP) and undertook an investigation in patients with complex ICA aneurysms treated with ECA-graft-MCA bypass and therapeutic ICAO. METHODS In the period between July 2006 and January 2016, 80 patients with complex ICA aneurysms were treated with ECA-MCA bypass and therapeutic ICAO. Preoperative balloon test occlusion (BTO) was performed, and the BTO pressure ratio was defined as the mean stump pressure/mean preocclusion pressure. Low flow-related ischemic complications were defined as new postoperative neurological deficits and ipsilateral cerebral blood flow reduction. Initial MCAP (iMCAP), MCAP after clamping the ICA (cMCAP), and MCAP after releasing the graft (gMCAP) were intraoperatively monitored. The MCAP ratio was defined as gMCAP/iMCAP. Based on the Hagen-Poiseuille law, the expected MCAP ratio ([expected gMCAP]/iMCAP) was hypothesized as follows: (1 - cMCAP/iMCAP)(graft radius/ICA radius)² + (cMCAP/iMCAP). Correlations between the BTO pressure ratio and cMCAP/iMCAP, and between the actual and expected MCAP ratios, were evaluated. Risk factors for LRICs were also evaluated. RESULTS The mean BTO pressure ratio was significantly correlated with the mean cMCAP/iMCAP (r = 0.68, p < 0.0001). The actual MCAP ratio correlated with the expected MCAP ratio (r = 0.43, p < 0.0001). If the expected MCAP ratio was set up using the BTO pressure ratio instead of cMCAP/iMCAP (BTO-expected MCAP ratio), the mean BTO-expected MCAP ratio significantly correlated with the expected MCAP ratio (r = 0.95, p < 0.0001). During a median follow-up period of 26.1 months, LRICs were observed in 9 patients (11%). An actual MCAP ratio < 0.80 (p = 0.003), expected MCAP ratio < 0.80 (p = 0.001), and (M₂ radius/graft radius)² < 0.49 (p = 0.002) were related to LRICs according to the Cox proportional-hazards model. CONCLUSIONS Data in the present study indicated that it was important to use an adequate graft to achieve a sufficient MCAP ratio in order to avoid LRICs and that the adequate graft size could be evaluated based on a formula in patients with complex ICA aneurysms treated with ICAO.

Bypass surgery for complex middle cerebral artery aneurysms: an algorithmic approach to revascularization

OBJECT Management of complex aneurysms of the middle cerebral artery (MCA) can be challenging. Lesions not amenable to endovascular techniques or direct clipping might require a bypass procedure with aneurysm obliteration. Various bypass techniques are available, but an algorithmic approach to classifying these lesions and determining the optimal bypass strategy has not been developed. The objective of this study was to propose a comprehensive and flexible algorithm based on MCA aneurysm location for selecting the best of multiple bypass options. METHODS Aneurysms of the MCA that required bypass as part of treatment were identified from a large prospectively maintained database of vascular neurosurgeries. According to its location relative to the bifurcation, each aneurysm was classified as a prebifurcation, bifurcation, or postbifurcation aneurysm. RESULTS Between 1998 and 2015, 30 patients were treated for 30 complex MCA aneurysms in 8 (27%) prebifurcation, 5 (17%) bifurcation, and 17 (56%) postbifurcation locations. Bypasses included 8 superficial temporal artery-MCA bypasses, 4 high-flow extracranial-to-intracranial (EC-IC) bypasses, 13 IC-IC bypasses (6 reanastomoses, 3 reimplantations, 3 interpositional grafts, and 1 in situ bypass), and 5 combination bypasses. The bypass strategy for prebifurcation aneurysms was determined by the involvement of lenticulostriate arteries, whereas the bypass strategy for bifurcation aneurysms was determined by rupture status. The location of the MCA aneurysm in the candelabra (Sylvian, insular, or opercular) determined the bypass strategy for postbifurcation aneurysms. No deaths that resulted from surgery were found, bypass patency was 90%, and the condition of 90% of the patients was improved or unchanged at the most recent follow-up. CONCLUSIONS The bypass strategy used for an MCA aneurysm depends on the aneurysm location, lenticulostriate anatomy, and rupture status. A uniform bypass strategy for all MCA aneurysms does not exist, but the algorithm proposed here might guide selection of the optimal EC-IC or IC-IC bypass technique.

A case of bilateral giant internal carotid artery aneurysms at the cavernous portion managed by 2-stage extracranial-intracranial bypass with parent artery occlusion: consideration for bypass selection and timing of surgeries

Bilateral giant internal carotid artery (ICA) aneurysms at the cavernous portion with bilateral cranial nerve symptoms are extremely rare. Extracranial-intracranial (EC-IC) bypass with parent artery occlusion (PAO) is one of the preferred procedures for giant ICA aneurysm at the cavernous portion with cranial nerve palsy; however, optimal bypass selection and the timing of surgery are controversial, particularly in bilateral cases. A 28-year-old woman developed left third nerve palsy with giant ICA aneurysms at the bilateral cavernous portion. Because only the left aneurysm was symptomatic, she initially underwent left EC-IC bypass using a saphenous vein graft with PAO without complications, which relieved her symptoms. However, she developed right third/fifth nerve palsy 10 months later, at which time magnetic resonance (MR) imaging and MR angiography revealed an enlarged right ICA aneurysm and shrunken left ICA aneurysm. Balloon test occlusion of the right ICA identified sufficient ischemic tolerance; therefore, she underwent right superficial temporal artery-middle cerebral artery bypass with PAO. Both bypasses were confirmed by MR angiography to be patent after surgery. Cranial nerve palsy gradually improved postoperatively, and single-photon emission computed tomography confirmed static cerebral hemodynamics. In conclusion, high-flow EC-IC bypass with PAO is recommended in the first stage of surgery on a unilaterally symptomatic side to minimize postoperative hemodynamic stress to the contralateral aneurysm. Once the contralateral side becomes symptomatic, second stage EC-IC bypass with PAO, either low-flow or high-flow bypass, is recommended based on the results of balloon test occlusion.

Staged hybrid open and endovascular exclusion of a symptomatic thoracoabdominal aortic aneurysm in a high-risk patient

Thoracoabdominal aortic aneurysms have a higher prevalence in the elderly, who are often poor surgical candidates. These extensive aneurysms may be lethal if left untreated. Conventional open repair has proven to be a major task, involving cardiopulmonary bypass, aortic cross-clamping and expeditious repair of an inaccessible structure involving two body cavities. Endovascular repair has become a viable option to treat isolated descending thoracic aneurysms and infrarenal abdominal aortic aneurysms. However, endovascular techniques alone have been less applicable for treating complex aortic aneurysms, including those involving visceral vessels. Therefore, a hybrid open and endovascular approach with visceral debranching has become an increasingly favorable alternative for patients with these complex conditions. We report a case in which a staged hybrid approach was used for successful exclusion of an extensive thoracoabdominal aortic aneurysm in a symptomatic, high-risk patient who would not have been an appropriate candidate for open surgical repair.