Arjan W. J. Hoksbergen

Pararenal aortic aneurysm repair using fenestrated endografts

OBJECTIVE We performed a systematic review of the current literature to analyze the immediate and follow-up results of fenestrated endovascular aortic aneurysm repair (F-EVAR) in patients with pararenal abdominal aortic aneurysms (AAAs). METHODS The Medline, Embase, and Cochrane databases were searched to identify all studies reporting F-EVAR of pararenal AAAs published between January 2000 and May 2011. Two independent observers selected studies for inclusion, assessed the quality of the included studies, and performed the data extraction. Studies were selected based on specific predefined criteria. Outcomes were technical success (successfully completed procedure with endograft patency, preservation of target vessels, and no evidence of type I or III endoleak at postprocedural imaging), 30-day mortality, all-cause mortality, branch vessel patency, renal impairment, and secondary interventions. Between-study heterogeneity was calculated using I(2) statistics. Pooled estimates were calculated using a fixed-effects (I(2) <25%) or a random-effects (I(2) >25% to <50%) model. RESULTS Nine studies were included reporting 629 patients who underwent F-EVAR for a pararenal AAA, of which 1622 target vessels were incorporated in an endograft design. Between-study heterogeneity was ≤ 41% for all outcomes. The pooled estimate (95% confidence interval [CI] was 90.4% (87.7%-92.5%) for technical success, 2.1% (1.2%-3.7%) for 30-day mortality, and 16% (12.5%-20.4%) for all-cause mortality. Follow-up was 15 to 25 months. The pooled estimate (95% CI) during follow-up was 93.2% (90.4%-95.3%) for branch vessel patency, 22.2% (16%-30.1%) for renal impairment, and 17.8% (13.5%-22.6%) for secondary interventions. CONCLUSIONS Promising immediate and midterm results (up to 2 years) support F-EVAR as a feasible, safe, and effective treatment in a relatively high-risk cohort of patients with pararenal AAAs.

Open surgical repair of ruptured juxtarenal aortic aneurysms with and without renal cooling: Observations regarding morbidity and mortality

OBJECTIVES Little is known about the outcome of ruptured juxtarenal aortic aneurysm (RJAA) repair. Surgical treatment of RJAAs requires suprarenal aortic cross-clamping, which causes additional renal ischemia-reperfusion injury on top of the pre-existing hypovolemic shock syndrome. As endovascular alternatives rarely exist in this situation, open repair continues to be the gold standard. We analyzed our results of open RJAA repair during an 11-year period. DESIGN Retrospective observational study. MATERIALS AND METHODS Between July 1997 and December 2008, all consecutive patients with RJAAs were included in the study. Part of these patients received cold perfusion of the kidneys during suprarenal aortic cross-clamping. Perioperative variables, morbidity, and 30-day or in-hospital mortality were assessed. Renal insufficiency was defined as an acute rise of >or=0.5 mg/dL in serum creatinine level. Multiple organ failure (MOF) was scored using the sequential organ failure assessment score (SOFA score). RESULTS A total of 29 consecutive patients with an RJAA, confirmed by computed tomography-scanning, presented to our hospital. In eight patients, the operation was aborted before the start of aortic repair, because no blood pressure could be regained in spite of maximal resuscitation measures. They were excluded from further analysis. Of the remaining 21 patients, 10 died during hospital stay. Renal insufficiency occurred in 11 out of 21 of the patients. Eleven out of 21 patients developed MOF postoperatively. In a subgroup of patients who received renal cooling during suprarenal aortic clamping, the 30-day or in-hospital mortality was two of 10 vs eight of 11 in patients who did not receive renal cooling (P = .03); renal insufficiency occurred in one out of 10 patients in the subgroup with renal cooling vs 10 out of 11 without renal cooling (P < .001) and MOF in two of 10 vs nine of 11, respectively (P = .009). CONCLUSIONS Open surgical repair of RJAAs is still associated with high mortality and morbidity. To our knowledge, this is the first report of cold perfusion of the kidneys during RJAA repair. Although numbers are small, a beneficial effect of renal cooling on the outcome of RJAA repair is suggested, warranting further research with this technique.

Direct videoscopic approach to the thoracic aorta for aortic endograft delivery: evaluation in a human cadaver circulation model.

Purpose: To examine the feasibility of a direct videoscopic approach to the descending thoracic aorta for branched endograft delivery to the aortic arch and abdominal aorta. Methods: Aneurysms were created in the aortic arch and pararenal aorta of 3 human cadavers, and pulsatile flow was established using a roller pump. Thoracoscopically, 2 double-felted purse-string sutures were placed on the thoracic aorta. Via the most distal trocar, an endoscopic needle was used to insert a stiff guidewire into the aorta through the center of the purse-string suture. Under direct videoscopic control, a 20-F sheath was advanced over the wire into the aorta. Switching to fluoroscopic control, a fenestrated endograft was deployed in the aortic arch followed by placement of a branch graft into the left subclavian artery. The delivery sheath was withdrawn from the aorta while simultaneously tightening the purse-string sutures. A similar procedure was performed in the same cadaver for antegrade branched endograft delivery to the pararenal aorta. Correct deployment of the branched endografts was evaluated by post implant angiography and autopsy. Results: The procedure was successfully completed in all cadavers. “Hemostasis” was obtained in all cadavers without aortic cross clamping. Median fluid loss was 165 mL. Autopsy proved all purse-string sutures to be adequately placed and all branched endografts to be deployed in the correct position. Conclusion: A direct videoscopic approach to the descending thoracic aorta proved a feasible technique for branched endograft delivery to the aortic arch and abdominal aorta in a human cadaver model.

Dutch Randomized Trial Comparing Standard Catheter-Directed Thrombolysis and Ultrasound-Accelerated Thrombolysis for Arterial Thromboembolic Infrainguinal Disease (DUET):

Purpose: To report the results of the Dutch randomized trial comparing standard catheter-directed and ultrasound-accelerated thrombolysis (UST) for the treatment of arterial thromboembolic occlusions. Methods: The DUET study ( controlled-trials.com ; identifier ISRCTN72676102) was designed to assess whether UST can reduce therapy time significantly compared with standard thrombolysis (ST). Sixty patients (44 men; mean age 64 years) with recently (7–49 days) thrombosed infrainguinal native arteries or bypass grafts causing acute limb ischemia (Rutherford category I or IIa) were randomized to ST (n=32) or UST (n=28). The primary outcome was the duration of thrombolysis needed for uninterrupted flow (>95% thrombus lysis), with outflow through at least 1 below-the-knee artery. Continuous data are presented as means ± standard deviations. Results: Thrombolysis was significantly faster in the UST group (17.7±2.0 hours) than in the ST group (29.5±3.2 hours, p=0.009) and required significantly fewer units of urokinase (2.8±1.6×106 IU in the ST group vs. 1.8±1.0×106 IU in the UST group, p=0.01) for uninterrupted flow. Technical success was achieved in 27 (84%) patients in the ST group vs. 21 (75%) patients in the UST group (p=0.52). The combined 30-day death and severe adverse event rate was 19% in the ST group and 29% in the UST group (p=0.54). The 30-day patency rate was 82% in the ST group as compared with 71% in the UST group (p=0.35). Conclusion: Thrombolysis time was significantly reduced by UST as compared with ST in patients with recently thrombosed infrainguinal native arteries or bypass grafts.

Minimally Invasive, Laparoscopic, and Robotic-assisted Techniques Versus Open Techniques for Kidney Transplant Recipients: A Systematic Review

CONTEXT Literature on conventional and minimally invasive operative techniques has not been systematically reviewed for kidney transplant recipients. OBJECTIVE To systematically evaluate, summarize, and review evidence supporting operating technique and postoperative outcome for kidney transplant recipients. EVIDENCE ACQUISITION A systematic review was conducted in PubMed-Medline, Embase, and Cochrane Library between 1966 up to September 1, 2016, according to Preferred Reporting Items for Systematic Review and Meta-analysis guidelines. Articles were included and scored by two independent reviewers using Group Reading Assessment and Diagnostic Evaluation (GRADE), Newcastle-Ottawa Quality Assessment Scale (NOS), and Oxford guidelines for level of evidence. Main outcomes were graft survival, surgical site infection, incisional hernia, and cosmetic result. In total, 18 out of 1954 identified publications were included in this analysis. EVIDENCE SYNTHESIS Included reports described conventional open, minimally invasive open, laparoscopic, and robotic-assisted techniques. General level of evidence of included studies was low (GRADE: 1-3; NOS: 0-4; and Oxford level of evidence: 4-2). No differences in graft or patient survival were found. For open techniques, Gibson incision showed better results than the hockey-stick incision for incisional hernia (4% vs 16%), abdominal wall relaxation (8% vs 24%), and cosmesis. Minimally invasive operative recipient techniques showed lowest surgical site infection (range 0-8%) and incisional hernia rates (range 0-6%) with improved cosmetic result and postoperative recovery. Disadvantages included prolonged cold ischemia time, warm ischemia time, and total operation time. CONCLUSIONS Although the level of evidence was generally low, minimally invasive techniques showed promising results with regard to complications and recovery, and could be considered for use. For open surgery, the smallest possible Gibson incision appeared to yield favorable results. PATIENT SUMMARY In this paper, the available evidence for minimally invasive operation techniques for kidney transplantation was reviewed. The quality of the reviewed research was generally low but suggested possible advantages for minimally invasive, laparoscopic, and robot-assisted techniques.

Three-dimensional endovascular navigation with electromagnetic tracking.

At the present time, complex endovascular procedures with cannulation of multiple branch arteries are executed under guidance from 2-dimensional radiological imaging equipment, implying a considerable amount of ‘‘trial and error’’ during wire and catheter manipulation. In this issue of the JEVT, Manstad-Hulaas et al. describe a technique of 3-dimensional (3D) endovascular navigation with electromagnetic (EM) tracking that conceptually could address the above mentioned shortcoming and, additionally, could reduce the amount of radiation required for these often long procedures. To elucidate the potential of their method, the authors have moved along the correct lines of applying in vitro studies first, followed by animal research, in preparation for possible human application. What surprised me in reading the article, however, is how distant and abstract one can make the description of a relatively simple process, which for most of us can be summarized as ‘‘fixing pipes.’’ I understand there is a certain distinct nomenclature that these EM navigators have coined to describe their work; however, one of the prime assets of a good doctor or scientist is the ability to make complicated matters look simple. This is certainly not the forte of these authors; perhaps in future they can include a vascular surgeon in the research group. Nonetheless, if one sets aside the initial resistance to unexplored territory common to many of us simple surgeons and radiologists, then the reader may find a lot of potentially valuable information hiding in this article. The authors have meticulously tested this new concept mainly with regard to accuracy, which they defined as the degree of conformity found between EM-tracked positions in the navigation system and their corresponding positions in the computed tomography (CT) image space, a type of accuracy they referred to as target registration error (TRE). They conclude that the mean accuracy in the swine model was 4.1861.76 mm, and 90% of the measured distances were #5.73 mm. As I understand, this means that if one would intend to cannulate an aortic side branch, the representation of the branch could be 4 to 5 mm away from the truth, which then presumably would be true for the impression of the catheter tip position as well. The authors may state that neurosurgeons are happy with a TRE of 5 mm, which surprises me, but errors of up to 1 cm, in my opinion, will not completely eliminate the ‘‘trial and error’’ from endovascular surgery. I am confident, however, that rapid advancement of the navigation technique will overcome these inaccuracies in the very near future. In addition, the third dimension offered by this technique could bring us further in the quest of being able to direct catheters exactly where we want them. Until then, however, I

Commentary: Endovascular Aneurysm Sealing for Ruptured Abdominal Aortic Aneurysms: Does It Work?

Although the (r)evolution of endovascular aneurysm sealing (EVAS) for elective abdominal aortic aneurysm (AAA) repair has just started, the avant-garde of this exciting new technique already are exploring new horizons. While a substantial part of the endovascular world is still questioning the working mechanism and durability of EVAS, these early enthusiasts are inserting the Nellix Endovascular Aneurysm Sealing System (Endologix Inc, Irvine, CA, USA) in aortic anatomies that were previously considered totally unsuitable for endovascular repair. Although the instructions for use (IFU) of the Nellix system have restrictions that are largely similar to standard stent-grafts, this device in particular seems to seduce vascular surgeons to go outside the IFU. The essential difference between EVAS and standard endovascular aneurysm repair (EVAR) is that the endobags are used to provide anatomical fixation in the aneurysm sac with complete elimination of the sac lumen and seal of side branch flow, as well as providing a proximal and distal seal in, respectively, the aortic neck and iliac arteries. The main question that is raised is whether this sac-anchoring system provides a true seal of the aneurysm sac, in which case a seal in the aortic neck and iliac arteries would seem less important, or provides some sort of fixation in the sac only. Probably the main reason to use the Nellix device outside of IFU, with treatment of short necks or even no-necks, conical necks, large neck angulations, and wide necks, is the belief that the seal in the aneurysm sac is enough for a successful and durable aortic repair. Recently, 2 large EVAS studies were published. In the single-center study of Brownrigg et al, which reported 30-day outcomes of EVAS in 105 patients with non-ruptured AAAs, 69% of patients had adverse neck morphology. Technical success was achieved in 97% and 30-day mortality was 1%. The incidence of type I endoleaks within 30 days was 4%, all successfully treated with transcatheter embolization. There was no type II or III endoleak. Angioplasty and adjunctive stenting were performed for postoperative limb stenosis in 3% of the patients. In the large multicenter study of Böckler et al, 171 patients were treated with EVAS, 169 with intact AAAs and 2 with ruptured aneurysms. Anatomic measurements were outside the IFU in 33% of the patients. Technical success was 99%, and 30-day mortality was 0% in 130 patients with completed 30-day follow-up. Device occlusions occurred in 5% of the patients. Type Ia, type Ib, and type II endoleaks were reported in 3%, 2%, and 4% of the patients, respectively; there were no type III endoleaks. Both studies concluded that the Nellix EVAS system appears to have a reasonable short-term outcome and that patient selection and procedural evolution will further enhance outcome. However, definite conclusions regarding the utility of EVAS will be defined by the durability of the device in long-term follow-up. Compared with regular abdominal aortic stent-grafts, the Nellix system would be a particularly attractive alternative for the treatment of ruptured AAAs (RAAA). Sizing is fast and easy and basically requires only length measurements; as a result, only a small inventory of devices is needed. There is no time-consuming contralateral limb cannulation, and early hemostasis can be achieved through endobag inflation with saline (the “prefill”), while maintaining limb perfusion. Furthermore, patients with unsuitable aortic anatomy for treatment with currently available stent-grafts might be successfully treated with Nellix as shown by the 2 studies 599606 JETXXX10.1177/1526602815599606Journal of Endovascular TherapyHoksbergen research-article2015

Surgical Treatment of Renal Fibromuscular Dysplasia in a Young Child.

During a routine checkup in a 10-year-old male with Attention-Deficit Hyperactivity Disorder, blood pressure of 180/120 mmHg was found. Physical examination was completely normal. Ultrasound examination showed poststenotic dilatation of the left renal artery which was confirmed by CT-angiography showing a short, high grade stenosis of the left renal artery. Percutaneous Transluminal Angioplasty of the stenosis was not successful and therefore the stenosis was excised with reimplantation of the renal artery in the aorta. Pathological examination of the excised segment showed media-type Fibromuscular Dysplasia (FMD). Six years after surgery, the kidney is completely normal regarding size and function. There are no signs of restenosis of the left renal artery. Nevertheless, the hypertension remained although less severe and requiring less medication.

An in vitro method to keep human aortic tissue sections functionally and structurally intact

The pathophysiology of aortic aneurysms (AA) is far from being understood. One reason for this lack of understanding is basic research being constrained to fixated cells or isolated cell cultures, by which cell-to-cell and cell-to-matrix communications are missed. We present a new, in vitro method for extended preservation of aortic wall sections to study pathophysiological processes. Intraoperatively harvested, live aortic specimens were cut into 150 μm sections and cultured. Viability was quantified up to 92 days using immunofluorescence. Cell types were characterized using immunostaining. After 14 days, individual cells of enzymatically digested tissues were examined for cell type and viability. Analysis of AA sections (N = 8) showed a viability of 40% at 7 days and smooth muscle cells, leukocytes, and macrophages were observed. Protocol optimization (N = 4) showed higher stable viability at day 62 and proliferation of new cells at day 92. Digested tissues showed different cell types and a viability up to 75% at day 14. Aortic tissue viability can be preserved until at least 62 days after harvesting. Cultured tissues can be digested into viable single cells for additional techniques. Present protocol provides an appropriate ex vivo setting to discover and study pathways and mechanisms in cultured human aneurysmal aortic tissue.

Commentary: Endovascular Aneurysm Sealing With the Nellix Device: A Panacea for Ruptured Aneurysms?

Since the introduction of endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysms (RAAA), it was expected that the mortality of this devastating condition would significantly fall. Although many reports are published that indeed showed lower mortality than historical series of open repair, well-designed randomized studies of RAAA, such as the Amsterdam Acute Aneurysm Trial (AJAX) and the Immediate Management of the Patient with Rupture: Open versus Endovascular Repair (IMPROVE) trial, failed to show superiority of EVAR over open repair with regard to death, severe complications, or cost. Despite these unexpected and somewhat disappointing results, EVAR still is the first-choice treatment of RAAA in many specialized centers, and surgeons treating these patients are proud to report their constantly increasing percentage of RAAA patients treated with EVAR. Probably their efforts will finally result in superior outcome for EVAR as experience with open repair, elective and acute, is dramatically decreasing. Nowadays, residents and fellows in vascular surgery in the Netherlands are complaining that they lack sufficient skills for a proper open aortic repair. By contrast, their experience not only in straightforward EVAR for elective AAA but also in advanced EVAR, such as fenestrated and branched repairs, chimney grafts, and RAAA, is rapidly growing. Furthermore, centralization of aneurysm care, 24/7 availability of well-trained endovascular specialists, the rapid increase of specialized centers with computed tomography scanners at the emergency department, and easily accessible hybrid operating rooms will certainly have positive effects on outcome of emergency EVAR for RAAA. The IMPROVE and AJAX trial showed that with such improved logistics, not only the 30-day mortality of EVAR for RAAA (35% and 21%, respectively) but also the mortality of open repair (37% and 25%, respectively), is significantly lower than the 48.5% reported in a meta-analysis of open repair for RAAA. Major causes of death and severe complications in the endovascularly treated patients in both trials were intraoperative conversion from endovascular to open repair and additional surgical procedures due to misjudgment of anatomical suitability and consequent access failure, malpositioning of stent-grafts, and persisting endoleak. One of the main recommendations of the IMPROVE trial therefore was that identifying realistic candidates for endovascular repair is crucial to improving clinical outcomes. Use of newer endovascular devices with a broader applicability and potentially fewer conversions might have a positive effect on EVAR outcome as well. This would mean that such a device should ideally overcome access problems caused by small caliber or stenosed iliac arteries, should be easy to position and quick to deploy, and should be able to treat difficult aortic anatomies because it appears that ruptured aneurysms have shorter, wider, and more kinked infrarenal necks. Such a new device, or rather a totally new approach to the endovascular treatment of AAA, has recently been introduced and is called the Nellix Endovascular Aneurysm Sealing (EVAS) System. The Nellix device treats the aneurysm by filling the aneurysm sac and not by proximal and distal fixation as with regular endografts. Potential benefits are reduction of endoleaks and device migration. The 2 balloon-expandable stent-grafts, with surrounding endobags that need to be filled with a polymer solution that cures in situ, are deployed via relatively small 17-F sheaths. The length of the devices ranges from 140 to 180 mm; the 584147 JETXXX10.1177/1526602815584147Journal of Endovascular TherapyHoksbergen research-article2015