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Modern Treatment of Juxtarenal Abdominal Aortic Aneurysms with Fenestrated Endografting and Open Repair – A Systematic Review

Open ArchivePublished:April 06, 2009DOI:https://doi.org/10.1016/j.ejvs.2009.02.012

      Abstract

      Introduction

      Advances in endovascular technology have led to the introduction of fenestrated stents to treat juxtarenal aneurysms (JRAs), previously deemed unsuitable for standard endovascular repair (EVR). This article reviews the outcomes of fenestrated technology and makes a comparison with open repair.

      Methods

      A systematic review of the literature was performed.

      Results

      No randomised studies were identified. 8 cohort studies reporting 368 f-EVR cases and 12 cohorts reporting 1164 open repairs of JRAs were identified. Analysis of outcome measures found the f-EVR and open cohorts to be homogeneous. Combining studies identified an increased 30-day mortality after open repair when compared to f-EVR (Relative risk (RR) 1.03, 95% Confidence interval (CI) 1.01–1.04, p=.02), 2% increased absolute mortality. No difference was identified in postoperative permanent dialysis dependence (RR 1.00, CI 0.99–1.01, p=1). Transient renal failure was more common following open repair (RR 1.06, CI 1.01–1.12, p=.03). Early re-interventions were less common following open repair (RR 0.87, CI 0.83–0.91, p=.0001).

      Conclusions

      Selective f-EVR appears to have reduced peri-operative mortality compared with traditional open surgery, yet selectivity within the study groups and lack of a rigorous classification prohibit more robust comparison. Promising short-term results confirm a role for f-EVR in management of complex abdominal aneurysms.

      Keywords

      Introduction

      Endovascular abdominal aortic aneurysm repair (EVR) is associated with low peri-operative morbidity and mortality in patients with suitable aneurysm morphology. At least 55% of patients have aneurysms amenable to conventional EVR.
      Endovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1): randomised controlled trial.
      An inadequate landing zone for the graft below the renal vessels precludes conventional EVR requiring the patient to undergo open repair with the concomitant risks of suprarenal clamping.
      Endovascular technology has evolved to produce fenestrated stent-grafts designed to extend the proximal sealing zone from the infrarenal to the suprarenal aorta. The stent-graft fenestrations allow the visceral vessels to be incorporated into the repair. The simplest standard fenestrated device has two fenestrations for the renal ostia and a scallop in the covered stent to incorporate the superior mesenteric artery (SMA) origin (Fig. 1). As the complexity of the aneurysm morphology increases, a greater number of fenestrations can be customized into the graft, which correspondingly increases the technical challenges of deployment. The advantages of endovascular repair are maintained in f-EVR and the increased risks of these technically demanding open cases may be obviated.
      Figure thumbnail gr1
      Figure 1Segmented reconstruction of proximal fenestrated endograft.
      Good surgical candidates may tolerate open surgery, or “hybrid” open de-branching procedures combined with endovascular stent grafting. However, patients with significant cardiac, pulmonary or renal co-morbidity precluding safe open surgery have limited options and may be resigned to medical treatment.
      Fenestrated aortic grafts were first described in 1996 in 2 patients with infrarenal aortic aneurysms.
      • Park J.H.
      • Chung J.W.
      • Choo I.W.
      • Kim S.J.
      • Lee J.Y.
      • Han M.C.
      Fenestrated stent-grafts for preserving visceral arterial branches in the treatment of abdominal aortic aneurysms: preliminary experience.
      Development and clinical utilization of these grafts was led by Lawrence-Brown and associates.
      • Browne T.F.
      • Hartley D.
      • Purchas S.
      • Rosenberg M.
      • Van Schie G.
      • Lawrence-Brown M.
      A fenestrated covered suprarenal aortic stent.
      The Zenith (Cook, Brisbane, Australia) fenestrated stent-graft has been developed and can be custom manufactured based on individual patient aneurysm and visceral vessel morphology. Each stent-graft is designed based on computed tomographic angiography. The landing zone should lie in an area of normal aorta. Fenestrations are orientated based on the preoperative imaging. The fenestrations are reinforced with a nitinol ring and marked with radio-opaque markers to allow visualization at fluoroscopy. Graft markings and selective catheterisation of target vessels ensure correct deployment.
      There is no generally agreed definition for the term “juxtarenal aneurysm”. It is routinely used to describe a complex AAA with a short infrarenal neck or aneurysmal extension to the inter-renal aorta. Classification systems have been proposed but none have been widely adopted in clinical practice. There are no reporting standards which make interpretation and comparison of clinical studies difficult.
      • Crawford E.S.
      • Beckett W.C.
      • Greer M.S.
      Juxtarenal infrarenal abdominal aortic aneurysm. Special diagnostic and therapeutic considerations.
      • SVS/NAISCVS
      Suggested standards for reporting on arterial aneurysms.
      Juxtarenal aneurysms therefore encompass a broad spectrum of AAA complexity.
      To replace open repair, fenestrated endovascular aneurysm repair (f-EVR) must demonstrate safety, efficacy and durability. This systematic review examines the current evidence for utility of fenestrated stent-grafts in the management of juxtarenal aneurysms (JRAs). The review also compares results of f-EVR with recent published series of open surgical management of JRAs.

      Methods

      A systematic literature search of related articles published in the English language between 2001 and 2008 was carried out using PubMed and Embase databases. The keywords used for the literature search included “fenestrated grafts”, “juxtarenal aortic aneurysm”, “para-renal AAA”, “supra-renal AAA” and “Zenith graft”. Relevant medical journals were hand searched, and each relevant article retrieved had its references searched for missed reports.
      The inclusion criteria were published studies reporting experience with greater than 10 cases of f-EVR or open surgical management of juxtarenal abdominal aortic aneurysms. Exclusion criteria included replicate data publication, selective patient subgroup analysis and AAA ruptures. The outcome measures assessed were 30-day mortality, renal impairment, target vessel patency, length of stay and secondary re-intervention rate (Figure 2, Figure 3).
      Figure thumbnail gr2
      Figure 2Quorum charts representing literature searches for f-EVR papers.
      Figure thumbnail gr3
      Figure 3Quorum charts representing literature searches for open surgery papers.

      Statistical methods

      Cohort studies were assessed for heterogeneity using contingency tables & Fisher's exact test. Categorical outcomes within groups were pooled and compared using Fisher's exact test. All p values are two-sided and significant difference was defined at the 1:20 level of significance. Statistical analysis was performed using SPSS 16.0 (SPSS, Chicago, IL).

      Results

      In all, 8 endovascular studies were identified using the above mentioned search strategy. All series utilized Zenith fenestrated endografts (Cook Medical Inc., USA) for exclusion of JRAs reporting a total 368 cases. In the same time period 12 series were identified reporting experience with open surgery for JRAs, totaling 1164 cases.
      Analysis by Fisher's exact test excluded heterogeneity for outcomes within the open and f-EVR groups, respective p values .26 and .67. Pooling the demographic data confirmed that the groups were well matched for gender (p=.09), ischaemic heart disease (p=.35) and preoperative renal impairment (p=.5). There was a statistically significant difference in pooled ages (open cases mean age 71.8 (±2.4) vs. f-EVR 73.7 (±1.9), p=.0001) (Table 1).
      Table 1Grouped preoperative demographics and co-morbidities in open and f-EVR cohorts (where data available).
      f-EVROpenSig
      Gender (F/M)51/300200/8810.09
      Age (yr (±SD))71.8(±2.4)73.8(±1.9)0.0001
      Ischaemic heart disease55%58%0.35
      Renal disease24%22%0.5
      Case load, study design and 30-day mortality are shown in Table 2. There were no randomised controlled studies or cohort control data.
      Table 2Cohort studies included in analysis with associated mortality.
      First authorCountryYearType of studyn=30-day mortality (%)95% CI
      Fenestrated
      Anderson
      • Anderson J.L.
      • Berce M.
      • Hartley D.
      Endoluminal aortic grafting with renal and superior mesenteric artery incorporation by graft fenestration.
      Australia2001Prospective, Single centre1300–27
      Halak
      • Halak M.
      • Goodman M.A.
      • Baker S.R.
      The fate of target visceral vessels after fenestrated endovascular aortic repair – general considerations and mid-term results.
      Australia2006Single centre1700–22
      Muhs
      • Muhs B.E.
      • Verhoeven E.L.
      • Zeebregts C.J.
      • Tielliu I.F.
      • Prins T.R.
      • Verhagen H.J.M.
      • et al.
      Mid-term results of endovascular aneurysm repair with branched and fenestrated endografts.
      Netherlands2006Prospective, Single centre382.60.01–14.7
      O'neill
      • O'Neill S.
      • Greenberg R.K.
      • Haddad F.
      • Resch T.
      • Sereika J.
      • Katz E.
      A prospective analysis of fenestrated endovascular grafting: intermediate-term outcomes.
      USA2006Prospective, Single centre11910.01–5
      Semmens
      • Semmens J.B.
      • Lawrence-Brown M.
      • Hartley D.
      • Allen Y.B.
      • Green R.
      • Nadkarni S.
      Outcomes of fenestrated endografts in the treatment of abdominal aortic aneurysm in Western Australia.
      Australia2006Retrospective, Multicentre583.40.3–12.4
      Ziegler
      • Ziegler P.
      • Avgerinos E.D.
      • Umscheid T.
      • Perdikides T.
      • Stelter W.J.
      Fenestrated endografting for aortic aneurysm repair: a 7-year experience.
      Germany2007Retrospective, Single centre6300–6.8
      Scurr
      • Scurr J.R.H.
      • Brennan J.A.
      • Gilling-Smith G.L.
      • Harris P.L.
      • Vallabhaneni S.R.
      • McWilliams R.G.
      Fenestrated endovascular repair for juxtarenal aortic aneurysm.
      UK2008Retrospective, Single centre452.20.01–12.6
      Bicknell

      Bicknell CD, Cheshire NJW, Riga CV, Bourke P, Wolfe JHN, Gibbs RGJ, et al. Treatment of complex aneurysmal disease with fenestrated and branched stent grafts. Eur J Vasc Endovascular Surg 2009;37(2):175–81.

      UK2008Prospective, Single centre1500–23
      Open
      Ayari
      • Ayari R.
      • Paraskevas N.
      • Rosset E.
      • Ede B.
      • Branchereau A.
      Juxtarenal aneurysm. Comparative study with infrarenal abdominal aortic aneurysm and proposition of new classification.
      France2001Retrospective, Single centre53114.7–22
      Sarac
      • Sarac T.P.
      • Clair D.G.
      • Hertzer N.R.
      • Greenberg R.K.
      • Krajewski L.P.
      • O'Hara P.J.
      • et al.
      Contemporary results of juxtarenal aneurysm repair.
      USA2002Prospective, Single centre1385.12.3–10.3
      Bicknell
      • Bicknell C.D.
      • Cowan A.R.
      • Kerle M.I.
      • Mansfield A.O.
      • Cheshire N.J.
      • Wolfe J.H.
      Renal dysfunction and prolonged visceral ischaemia increase mortality rate after suprarenal aneurysm repair.
      UK2003Prospective, Single centre444.50.4–16
      Shortell
      • Shortell C.K.
      • Johansson M.
      • Green R.M.
      • Illig K.A.
      Optimal operative strategies in repair of juxtarenal abdominal aortic aneurysms.
      USA2003Retrospective, Single centre11262.9–12
      Kudo
      • Kudo F.A.
      • Nishibe T.
      • Miyazaki K.
      • Murashita T.
      • Yasuda K.
      • Ando M.
      • et al.
      Postoperative renal function after elective abdominal aortic aneurysm repair requiring suprarenal aortic cross-clamping.
      Japan2004Retrospective, Single centre1800–21
      Ryan
      • Ryan S.V.
      • Calligaro K.D.
      • McAffee-Bennett S.
      • Doerr K.J.
      • Chang J.
      • Dougherty M.J.
      Management of juxtarenal aortic aneurysms and occlusive disease with preferential suprarenal clamping via a midline transperitoneal incision: technique and results.
      USA2004Retrospective, Single centre4400–9.6
      Back
      • Back M.R.
      • Bandyk M.
      • Bradner M.
      • Cuthbertson D.
      • Johnson B.L.
      • Shames M.L.
      • et al.
      Critical analysis of outcome determinants affecting repair of intact aneurysms involving the visceral aorta.
      USA2005Retrospective, Single centre782.60.2–9.4
      Chiesa
      • Chiesa R.
      • Marone E.M.
      • Brioschi C.
      • Frigerio S.
      • Tshomba Y.
      • Melissano G.
      Open repair of pararenal aortic aneurysms: operative management, early results, and risk factor analysis.
      Italy2006Retrospective, Single centre1194.21.6–9.7
      West
      • West C.A.
      • Noel A.A.
      • Bower T.C.
      • Cherry Jr., K.J.
      • Gloviczki P.
      • Sullivan T.M.
      • et al.
      Factors affecting outcomes of open surgical repair of pararenal aortic aneurysms: a 10-year experience.
      USA2006Retrospective, Single centre2472.51–5.3
      Ockert
      • Ockert S.
      • Schumacher H.
      • Bockler D.
      • Malcherek K.
      • Hansmann J.
      • Allenberg J.
      Comparative early and midterm results of open juxtarenal and infrarenal aneurysm repair.
      Germany2007Case-Control355.70.6–19.5
      Pearce
      • Pearce J.D.
      • Edwards M.S.
      • Stafford J.M.
      • Deonanan J.K.
      • Davis R.P.
      • Corriere M.A.
      • et al.
      Open repair of aortic aneurysms involving the renal vessels.
      USA2007Retrospective, Single centre1502.70.8–6.9
      Knott
      • Knott A.W.
      • Kalra M.
      • Duncan A.A.
      • Reed N.R.
      • Bower T.C.
      • Hoskin T.L.
      • et al.
      Open repair of juxtarenal aortic aneurysms (JAA) remains a safe option in the era of fenestrated endografts.
      USA2008Retrospective, Single centre1260.80.01–4.8

      Mortality

      All studies reported 30-day mortality. Cumulative mortality following f-EVR was 5/368 (1.4%, 95% Confidence interval 0.4–3.1), and following open repair was 42/1164 (3.6%, CI 2.7–4.9). The comparative relative risk (RR) of open vs. f-EVR was 1.03 (95% Confidence interval 1.01–1.04, p=.02), confirming increased mortality risk associated with open repair in these reports. Causes of mortality following f-EVR included mesenteric ischaemia (n=2)
      • Muhs B.E.
      • Verhoeven E.L.
      • Zeebregts C.J.
      • Tielliu I.F.
      • Prins T.R.
      • Verhagen H.J.M.
      • et al.
      Mid-term results of endovascular aneurysm repair with branched and fenestrated endografts.
      • O'Neill S.
      • Greenberg R.K.
      • Haddad F.
      • Resch T.
      • Sereika J.
      • Katz E.
      A prospective analysis of fenestrated endovascular grafting: intermediate-term outcomes.
      and myocardial infarction (MI) (3),
      • Semmens J.B.
      • Lawrence-Brown M.
      • Hartley D.
      • Allen Y.B.
      • Green R.
      • Nadkarni S.
      Outcomes of fenestrated endografts in the treatment of abdominal aortic aneurysm in Western Australia.
      • Scurr J.R.H.
      • Brennan J.A.
      • Gilling-Smith G.L.
      • Harris P.L.
      • Vallabhaneni S.R.
      • McWilliams R.G.
      Fenestrated endovascular repair for juxtarenal aortic aneurysm.
      with no intra-operative deaths.
      The commonest cause of 30-day mortality in the open group was multi-organ failure (n=18), followed by MI (12), mesenteric ischaemia (8) and others (4). Two intra-operative deaths occurred.

      Renal impairment

      18/20 studies included in the review reported early transient renal failure. This was defined as an increase in serum creatinine to >2 mg/dl or by >30% compared to baseline in the peri-operative period. 52/348 (14.9%, CI 11.5–18.7) patients developed renal impairment following f-EVR, compared to 230/1146 (20%, CI 17.9–22.5). There was a statistically significant increase in transient renal impairment following open repair compared to f-EVR, with RR 1.06 (CI 1.01–1.12, p=.03) (Table 3).
      Table 3Incidence of transient and permanent renal impairment (values expressed as n(%)).
      First authorn=Renal failure n(%)Temporary dialysis n(%)Permanent dialysis n(%)
      Fenestrated
      Anderson
      • Anderson J.L.
      • Berce M.
      • Hartley D.
      Endoluminal aortic grafting with renal and superior mesenteric artery incorporation by graft fenestration.
      131(8)00
      Halak
      • Halak M.
      • Goodman M.A.
      • Baker S.R.
      The fate of target visceral vessels after fenestrated endovascular aortic repair – general considerations and mid-term results.
      1701(6)
      Muhs
      • Muhs B.E.
      • Verhoeven E.L.
      • Zeebregts C.J.
      • Tielliu I.F.
      • Prins T.R.
      • Verhagen H.J.M.
      • et al.
      Mid-term results of endovascular aneurysm repair with branched and fenestrated endografts.
      382(5)00
      O'neill
      • O'Neill S.
      • Greenberg R.K.
      • Haddad F.
      • Resch T.
      • Sereika J.
      • Katz E.
      A prospective analysis of fenestrated endovascular grafting: intermediate-term outcomes.
      11930(25)4(3)3(2)
      Semmens
      • Semmens J.B.
      • Lawrence-Brown M.
      • Hartley D.
      • Allen Y.B.
      • Green R.
      • Nadkarni S.
      Outcomes of fenestrated endografts in the treatment of abdominal aortic aneurysm in Western Australia.
      584(6.9)00
      Ziegler
      • Ziegler P.
      • Avgerinos E.D.
      • Umscheid T.
      • Perdikides T.
      • Stelter W.J.
      Fenestrated endografting for aortic aneurysm repair: a 7-year experience.
      6314(22)01(2)
      Scurr
      • Scurr J.R.H.
      • Brennan J.A.
      • Gilling-Smith G.L.
      • Harris P.L.
      • Vallabhaneni S.R.
      • McWilliams R.G.
      Fenestrated endovascular repair for juxtarenal aortic aneurysm.
      45000
      Bicknell

      Bicknell CD, Cheshire NJW, Riga CV, Bourke P, Wolfe JHN, Gibbs RGJ, et al. Treatment of complex aneurysmal disease with fenestrated and branched stent grafts. Eur J Vasc Endovascular Surg 2009;37(2):175–81.

      151(7)1(7)0
      Open
      Ayari
      • Ayari R.
      • Paraskevas N.
      • Rosset E.
      • Ede B.
      • Branchereau A.
      Juxtarenal aneurysm. Comparative study with infrarenal abdominal aortic aneurysm and proposition of new classification.
      5311(21)29(4)0
      Sarac
      • Sarac T.P.
      • Clair D.G.
      • Hertzer N.R.
      • Greenberg R.K.
      • Krajewski L.P.
      • O'Hara P.J.
      • et al.
      Contemporary results of juxtarenal aneurysm repair.
      13839(28.3)8(5.8)
      Bicknell
      • Bicknell C.D.
      • Cowan A.R.
      • Kerle M.I.
      • Mansfield A.O.
      • Cheshire N.J.
      • Wolfe J.H.
      Renal dysfunction and prolonged visceral ischaemia increase mortality rate after suprarenal aneurysm repair.
      446(14)00
      Shortell
      • Shortell C.K.
      • Johansson M.
      • Green R.M.
      • Illig K.A.
      Optimal operative strategies in repair of juxtarenal abdominal aortic aneurysms.
      11214(12)4(3)0
      Kudo
      • Kudo F.A.
      • Nishibe T.
      • Miyazaki K.
      • Murashita T.
      • Yasuda K.
      • Ando M.
      • et al.
      Postoperative renal function after elective abdominal aortic aneurysm repair requiring suprarenal aortic cross-clamping.
      181(5)0
      Ryan
      • Ryan S.V.
      • Calligaro K.D.
      • McAffee-Bennett S.
      • Doerr K.J.
      • Chang J.
      • Dougherty M.J.
      Management of juxtarenal aortic aneurysms and occlusive disease with preferential suprarenal clamping via a midline transperitoneal incision: technique and results.
      443(6.8)01(1.7)
      Back
      • Back M.R.
      • Bandyk M.
      • Bradner M.
      • Cuthbertson D.
      • Johnson B.L.
      • Shames M.L.
      • et al.
      Critical analysis of outcome determinants affecting repair of intact aneurysms involving the visceral aorta.
      7812(15)0
      Chiesa
      • Chiesa R.
      • Marone E.M.
      • Brioschi C.
      • Frigerio S.
      • Tshomba Y.
      • Melissano G.
      Open repair of pararenal aortic aneurysms: operative management, early results, and risk factor analysis.
      11922(18.5)3(2.5)4(3.4)
      West
      • West C.A.
      • Noel A.A.
      • Bower T.C.
      • Cherry Jr., K.J.
      • Gloviczki P.
      • Sullivan T.M.
      • et al.
      Factors affecting outcomes of open surgical repair of pararenal aortic aneurysms: a 10-year experience.
      24754(22)9(3.7)0
      Ockert
      • Ockert S.
      • Schumacher H.
      • Bockler D.
      • Malcherek K.
      • Hansmann J.
      • Allenberg J.
      Comparative early and midterm results of open juxtarenal and infrarenal aneurysm repair.
      3525(71)6(17)0
      Pearce
      • Pearce J.D.
      • Edwards M.S.
      • Stafford J.M.
      • Deonanan J.K.
      • Davis R.P.
      • Corriere M.A.
      • et al.
      Open repair of aortic aneurysms involving the renal vessels.
      15022(14)11(7)
      Knott
      • Knott A.W.
      • Kalra M.
      • Duncan A.A.
      • Reed N.R.
      • Bower T.C.
      • Hoskin T.L.
      • et al.
      Open repair of juxtarenal aortic aneurysms (JAA) remains a safe option in the era of fenestrated endografts.
      12622(18)5(4)1(0.8)

      Dialysis

      Postoperative dialysis dependence is a reflection of failure to maintain the renal perfusion. Temporary extracorporeal renal support is often required in multi-organ failure. Permanent dialysis dependence was a complication in 5/368 (1.4%, CI 0.5–3.1) f-EVRs and 14/1014 (1.4%, CI 0.8–2.3) open repairs. No difference was identified between the groups, RR 1.00 (CI 0.99–1.01, p=1).

      Primary endoleak

      Primary type I and III endoleaks represent a failure to exclude the aneurysm. Type II endoleaks may have less clinical significance. All f-EVR studies reported their post-procedure endoleak rate (Table 4). 22/368 cases exhibited type I or type III endoleaks at end or immediate post-procedural imaging. These were managed by additional Palmaz stenting, balloon expandable stenting or conservative observation.
      Table 4Primary Endoleak rate in f-EVR studies (n(%)).
      First authorType I EndoleakType II endoleakType III endoleak
      Anderson
      • Anderson J.L.
      • Berce M.
      • Hartley D.
      Endoluminal aortic grafting with renal and superior mesenteric artery incorporation by graft fenestration.
      02(15)
      Halak
      • Halak M.
      • Goodman M.A.
      • Baker S.R.
      The fate of target visceral vessels after fenestrated endovascular aortic repair – general considerations and mid-term results.
      07(18)
      Muhs
      • Muhs B.E.
      • Verhoeven E.L.
      • Zeebregts C.J.
      • Tielliu I.F.
      • Prins T.R.
      • Verhagen H.J.M.
      • et al.
      Mid-term results of endovascular aneurysm repair with branched and fenestrated endografts.
      1(3)19(16)
      O'neill
      • O'Neill S.
      • Greenberg R.K.
      • Haddad F.
      • Resch T.
      • Sereika J.
      • Katz E.
      A prospective analysis of fenestrated endovascular grafting: intermediate-term outcomes.
      7(6)2(3)4(3)
      Semmens
      • Semmens J.B.
      • Lawrence-Brown M.
      • Hartley D.
      • Allen Y.B.
      • Green R.
      • Nadkarni S.
      Outcomes of fenestrated endografts in the treatment of abdominal aortic aneurysm in Western Australia.
      4(7)
      Ziegler
      • Ziegler P.
      • Avgerinos E.D.
      • Umscheid T.
      • Perdikides T.
      • Stelter W.J.
      Fenestrated endografting for aortic aneurysm repair: a 7-year experience.
      4(6)1(2)
      Scurr
      • Scurr J.R.H.
      • Brennan J.A.
      • Gilling-Smith G.L.
      • Harris P.L.
      • Vallabhaneni S.R.
      • McWilliams R.G.
      Fenestrated endovascular repair for juxtarenal aortic aneurysm.
      1(2)
      Bicknell

      Bicknell CD, Cheshire NJW, Riga CV, Bourke P, Wolfe JHN, Gibbs RGJ, et al. Treatment of complex aneurysmal disease with fenestrated and branched stent grafts. Eur J Vasc Endovascular Surg 2009;37(2):175–81.

      0

      Target vessel patency (TVP)

      TVP is a measure of primary technical success and f-EVR stability. All the endovascular series reported primary technical branch success, and 7/8 reported TVP at follow-up. 823/852 (96.6%, CI 95.4–97.8) of target vessels were preserved at primary surgery. 6/8 studies reported median follow-up >1 year, of these 1 study did not report follow-up TVP. In the remaining studies one-year patency had reduced to 423/460 (92%, CI 90.3–94.8). In this period no patient developed new dialysis dependent renal failure (Table 5).
      Table 5Aneurysm morphology, primary and follow-up target vessel patency and secondary re-interventions in the f-EVR group (* median (range) ** median (IQR)).
      First authorn=Target vessels (n=)Fenestrations/patientAneurysm neck length (mean±SD(range))Technical success branch (%)Target vessel patency 1 y (%)Early re-interventions n (%)
      Anderson
      • Anderson J.L.
      • Berce M.
      • Hartley D.
      Endoluminal aortic grafting with renal and superior mesenteric artery incorporation by graft fenestration.
      13332.55±6.5(0–20)100970
      Halak
      • Halak M.
      • Goodman M.A.
      • Baker S.R.
      The fate of target visceral vessels after fenestrated endovascular aortic repair – general considerations and mid-term results.
      17352.059189
      Muhs
      • Muhs B.E.
      • Verhoeven E.L.
      • Zeebregts C.J.
      • Tielliu I.F.
      • Prins T.R.
      • Verhagen H.J.M.
      • et al.
      Mid-term results of endovascular aneurysm repair with branched and fenestrated endografts.
      38872.394923(8)
      O'neill
      • O'Neill S.
      • Greenberg R.K.
      • Haddad F.
      • Resch T.
      • Sereika J.
      • Katz E.
      A prospective analysis of fenestrated endovascular grafting: intermediate-term outcomes.
      1193022.58±4(3–18)99.714(12)
      Semmens
      • Semmens J.B.
      • Lawrence-Brown M.
      • Hartley D.
      • Allen Y.B.
      • Green R.
      • Nadkarni S.
      Outcomes of fenestrated endografts in the treatment of abdominal aortic aneurysm in Western Australia.
      58116290.590.514(24)
      Ziegler
      • Ziegler P.
      • Avgerinos E.D.
      • Umscheid T.
      • Perdikides T.
      • Stelter W.J.
      Fenestrated endografting for aortic aneurysm repair: a 7-year experience.
      631221.9496.792.613(21)
      Scurr
      • Scurr J.R.H.
      • Brennan J.A.
      • Gilling-Smith G.L.
      • Harris P.L.
      • Vallabhaneni S.R.
      • McWilliams R.G.
      Fenestrated endovascular repair for juxtarenal aortic aneurysm.
      451172.66(0–13)*96.696.66(13)
      Bicknell

      Bicknell CD, Cheshire NJW, Riga CV, Bourke P, Wolfe JHN, Gibbs RGJ, et al. Treatment of complex aneurysmal disease with fenestrated and branched stent grafts. Eur J Vasc Endovascular Surg 2009;37(2):175–81.

      15402.60(0–3.8)**98970
      In the open series only one study reported renal artery patency following revascularisation.
      • Knott A.W.
      • Kalra M.
      • Duncan A.A.
      • Reed N.R.
      • Bower T.C.
      • Hoskin T.L.
      • et al.
      Open repair of juxtarenal aortic aneurysms (JAA) remains a safe option in the era of fenestrated endografts.
      An 85% renal artery patency rate in those patients attending review (6/14 patients) was described.

      Secondary re-intervention

      Secondary re-interventions included resolution of endoleaks, complications with access vessels and surgical excision of ischaemic viscera. 7/8 f-EVR studies reported their re-intervention rate in the first year following endograft deployment. 53/351 (15%, CI 11.5–18.7) patients (range 0–24%) required re-intervention. Indications for re-intervention in 48% of cases were endoleaks (Type I 21%, Type II 8%, Type III 19%). The remaining 52% included angioplasty of visceral or peripheral vessel stenoses, access and wound vessel complications, and laparotomy for mesenteric ischaemia.
      In the open studies reporting re-intervention, 14/532 (2.6%, CI 1.5–4.4) patients required surgical re-intervention, indications cited as bleeding, distal embolism and visceral ischaemia. Re-intervention was more commonly required after f-EVR (RR 0.87, CI 0.83–0.91, p=.0001).

      Discussion

      In this systematic review f-EVR was associated with a significant reduction in peri-operative mortality compared with open surgery for JRA. These results should however be interpreted with caution as they are based solely on small highly selective series with relatively short follow-up. Robust statistical comparison of f-EVR versus traditional open surgery would only be possible in a prospective randomised controlled trial. No such trial has been devised in the 10 years of evolution of f-EVR and it may never happen.
      Each of these papers reports their experience with JRAs. However JRA has no standardised classification system. An example of a proposed new classification system includes sub categorisation of juxtarenal AAAs into three groups; A- AAA extending just above inter-renal aorta, B- normal inter-renal aorta but aneurismal involvement of renal artery origins, C- JRA with normal inter-renal aorta and no renal artery involvement.
      • Ayari R.
      • Paraskevas N.
      • Rosset E.
      • Ede B.
      • Branchereau A.
      Juxtarenal aneurysm. Comparative study with infrarenal abdominal aortic aneurysm and proposition of new classification.
      In the endovascular era any new classification of JRA should include location, length, diameter and angulation of the aneurysm neck. The number of vessel ostia required to be incorporated into the repair, the atherosclerotic nature of visceral vessels as well as disease affecting access vessels must also be scored in a clinically useful classification.
      The advances in stent-graft technology now permit aneurysm necks ≤10 mm to be treated by classical EVR. However, in standard EVR the complication rates climb rapidly with increasing numbers of adverse features in the proximal neck.
      • Stanley B.M.
      • Semmens J.B.
      • Mai Q.
      • Goodman M.A.
      • Hartley D.E.
      • Wilkinson C.
      • et al.
      Evaluation of patient selection guidelines for endoluminal AAA repair with the Zenith Stent-Graft: the Australasian experience.
      The complexity of the aneurysm morphology is not clear in these cohort studies. Only 4/8 studies describe the aneurysm neck length, and 2/8 report the neck diameter (Table 5). This adds another note of caution in interpreting the results.
      This paper has compared in a case–control manner f-EVR with open surgical repair. The cases appeared well matched, yet each cohort is independently selective and will also be prone to reporting bias. The f-EVR cases from the USA are generally performed on patients deemed unfit for open surgery. This analysis has highlighted important differences and challenges of the two management strategies for JRAs.

      Procedural risks

      30-day mortality appears greater in the open surgical group compared to f-EVR (RR 1.03 CI 1.01–1.04). As this finding is not from a randomised study it must initially be interpreted with caution. Data is extracted from reports of the early experience of this technique. The selectivity of patients is not described in these series; the number of patients excluded deemed “high risk” (morphologically or physiologically) in either group is unclear. The early patients offered fenestrated grafts were selected as co-morbidities prohibited open surgery. This may explain the difference in ages between the two cohorts. Equally patients offered elective open JRA repair may be significantly fitter. Importantly f-EVR mortality does not appear to carry significantly greater risk of mortality when compared with accepted results for early EVR.
      Endovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1): randomised controlled trial.
      • Prinssen M.
      • Verhoeven E.L.
      • Buth J.
      • Cuypers P.W.M.
      • van Sambeek M.R.H.M.
      • Balm R.
      • et al.
      A randomized trial comparing conventional and endovascular repair of abdominal aortic aneurysms.
      Fenestrated grafts are designed precisely to maintain perfusion of visceral arterial branches close to the aneurysm. The key risk at the time of graft deployment is occlusion of these target vessel ostia. Selective catheterisation of these vessels reduces this risk. Instrumentation of these vessels may cause microembolisation resulting in visceral ischaemia or peripheral embolic events. This in combination with the increased contrast load may be a cause of the transient renal impairment observed.
      • Haddad F.
      • Greenberg R.K.
      • Walker E.
      • Nally J.
      • O'Neill S.
      • Kolin G.
      Fenestrated endovascular grafting: the renal side of the story.
      Fluoroscopy time required to accurately deploy fenestrated grafts is greater than conventional EVR.
      • Feezor R.
      • Huber T.S.
      • Martin T.D.
      • Beaver T.M.
      • Hess P.J.
      • Klodell C.T.
      • et al.
      Perioperative differences between endovascular repair of thoracic and abdominal aortic diseases.
      There is a corresponding increase in contrast load. Dilute contrast is used diligently when catheterising the visceral vessels.
      • Ricotta J.J.
      • Oderich G.S.
      Fenestrated and branched stent grafts.

      Additional challenges

      Not all JRAs are suitable for f-EVR. It is clear that a large number of patients are excluded from EVR due to inadequate aneurysm neck length.
      • Stanley B.M.
      • Semmens J.B.
      • Mai Q.
      • Goodman M.A.
      • Hartley D.E.
      • Wilkinson C.
      • et al.
      Evaluation of patient selection guidelines for endoluminal AAA repair with the Zenith Stent-Graft: the Australasian experience.
      There is as yet no data extrapolating this to identify the proportion of patients eligible for f-EVR.
      Anatomical factors can hamper the delivery of the device. The device introducer is 24 Fr gauge. After initial graft positioning it is critical to maintain torque to properly orientate the fenestrations. Significant angulation within the proximal neck, calcified or tortuous iliac anatomy will hamper this and increase the risk of acute branch vessel loss.
      • Greenberg R.K.
      • Haulon S.
      • Lyden S.P.
      • Srivastava S.D.
      • Turc A.
      • Eagleton M.J.
      • et al.
      Endovascular management of juxtarenal aneurysms with fenestrated endovascular grafting.
      Custom design and manufacture of these grafts excludes their utility in the acute setting. Current time to manufacture is 6 weeks. “Off-label” surgeon-modified devices have been described, on-site modifications of commercially available aortic endografts.
      • Uflacker R.
      • Robison J.D.
      • Schonholz C.
      • Ivancev K.
      Clinical experience with a customized fenestrated endograft for juxtarenal abdominal aortic aneurysm repair.
      Until an “off-the-shelf” device is created this remains the only option in emergencies where open repair is prohibited.
      The grouped re-intervention rate for f-EVR is 15% (0–24%). This is a consistent finding in EVR. Interventions appear to occur within the first postoperative year and subsequently plateau. Close surveillance is essential to identify visceral vessel stenosis or pre-occlusion. These results correlate with the findings of EVAR1, which highlighted a significantly increased re-intervention rate following endovascular exclusion of AAAs.
      Endovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1): randomised controlled trial.
      However the comparatively low re-intervention rate in the open group may be reflective of reporting bias, as EVAR1 reported a re-intervention rate in open AAAs of 7% which is greater than reported in these cohorts of more challenging JRA cases.
      The durability of fenestrated grafts has been questioned. Equally questions surround the fate of precisely positioned fenestrations following aneurysm exclusion. Aneurysm remodelling occurs following exclusion, the impact that this has on fenestrations remains unclear. The fate of the stents used to secure fenestrations has been questioned. The stents currently employed are not designed specifically for this purpose or to resist the forces to which they are exposed.
      • Scurr J.R.H.
      • How T.V.
      • McWilliams R.G.
      • Lane S.
      • Gilling-Smith G.L.
      Fenestrated stent-graft repair: which stent should be used to secure target vessel fenestrations.
      As the technology improves and durability is confirmed the indications for f-EVR may expand.

      Increased applicability

      The advantages of endoluminal treatment are numerous and well reported.
      • Schermerhorn M.L.
      • O'Malley A.J.
      • Jhaveri A.
      • Cotterill P.
      • Pomposelli F.
      • Landon B.E.
      Endovascular vs. open repair of abdominal aortic aneurysms in the Medicare population.
      The innovation of f-EVR will make more patients eligible for EVR. It also provides a treatment option above medical therapy for those patients unfit for open surgery. Although the utility of EVR in patients unfit for open surgery has been questioned,
      Endovascular aneurysm repair and outcome in patients unfit for open repair of abdominal aortic aneurysm (EVAR trial 2): randomised controlled trial.
      in patients with large high risk juxtarenal aneurysms, f-EVR warrants consideration.
      This technology requires considerable skill and experience to produce good results. Each of the series reviewed are reported from centres expert in advanced endovascular techniques. It is likely that the application of f-EVR will increase; yet advanced endovascular procedures will remain concentrated in centres of excellence.

      Limitations of study

      The limitations of this paper are centred on the reporting and possible publication bias of the series reviewed. 368 f-EVR cases are reported in these series up to the end of 2008, yet by 2006 over 1000 f-EVR stents had been deployed.
      Cook Inc.'s Zenith(R) fenestrated endograft successfully inplanted in 1,000th case to treat complex abdomnal aortic aneurysms.
      A similar argument can be applied to the open repair data. The overall 30-day mortality in the open series was 3.6%. This is less than the 4.7% and 4.6% reported in the EVAR1
      Endovascular aneurysm repair versus open repair in patients with abdominal aortic aneurysm (EVAR trial 1): randomised controlled trial.
      and DREAM
      • Prinssen M.
      • Verhoeven E.L.
      • Buth J.
      • Cuypers P.W.M.
      • van Sambeek M.R.H.M.
      • Balm R.
      • et al.
      A randomized trial comparing conventional and endovascular repair of abdominal aortic aneurysms.
      studies respectively. Whether these cohorts are truly representative of the general vascular surgical community is uncertain. It is essential to validate these advancing technologies and that accurate registries are maintained e.g. GLOBALSTAR project.
      • Vallabhaneni S.R.
      • Brennan J.A.
      • Buth J.
      • Harris P.L.
      • Haulon S.
      • Ivancev K.
      • et al.
      Global collaborators on advanced stent-graft techniques for aneurysm repair (GLOBALSTAR) project.

      Conclusion

      Short-term results regarding f-EVR confirm that this technique will have increasing utility in vascular surgery and may be a safer alternative to open surgical repair. The question of durability will only be answered with longer follow-up. Analysis of outcome would be more robust with a clear stratified classification system for juxtarenal aneurysm morphology. Now may be the time for a randomised study comparing f-EVR with open surgery to identify if f-EVR offers a lower risk alternative for the management of juxtarenal abdominal aortic aneurysms.

      Conflict of Interest/Funding

      None.

      Acknowledgement

      The authors would like to acknowledge the statistical guidance and assistance of Dr Jan Poloniecki.

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