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Endovascular Treatment of Infrarenal Abdominal Aortic Lesions With or Without Common Iliac Artery Involvement Article in CardioVascular and Interventional Radiology · February 2012 DOI: 10.1007/s00270-012-0357-5 · Source: PubMed
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Endovascular Treatment of Infrarenal Abdominal Aortic Lesions With or Without Common Iliac Artery Involvement Hakan Önder, Levent Oğuzkurt, Serkan Gür, Güven Tekbaş, Kamil Gürel, İsa Coşkun & Uğur Özkan CardioVascular and Interventional Radiology ISSN 0174-1551 Cardiovasc Intervent Radiol DOI 10.1007/s00270-012-0357-5
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Author's personal copy Cardiovasc Intervent Radiol DOI 10.1007/s00270-012-0357-5
Endovascular Treatment of Infrarenal Abdominal Aortic Lesions With or Without Common Iliac Artery Involvement ¨ nder • Levent Og˘uzkurt • Serkan Gu¨r Hakan O Gu¨ven Tekbas¸ • Kamil Gu¨rel • I˙sa Cos¸ kun • ¨ zkan Ug˘ur O
Received: 1 October 2011 / Accepted: 16 January 2012 Ó Springer Science+Business Media, LLC and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) 2012
Abstract Purpose To evaluate the results of stent placement for obstructive atherosclerotic aortic disease with or without involvement of the common iliac artery. Materials and Methods Forty patients had self-expanding stents primarily or after balloon dilatation in the abdominal aorta between January 2005 and May 2011. All patients had trouble walking. Follow-up examinations were performed with clinical visits; these included color Doppler ultrasonography and computed tomographic angiography. Results Technical, clinical, and hemodynamic success was achieved in all patients. None of the patients underwent reintervention during the follow-up period, which ranged from 3 months to 6 years (median 24 months). Nine complications occurred in six patients. Of the nine complications, four were distal thromboembolisms, which
¨ nder (&) G. Tekbas¸ H. O Department of Radiology, Dicle University Medical Faculty, Diyarbakir, Turkey e-mail: [email protected]
¨ zkan L. Og˘uzkurt U. O Department of Radiology, Bas¸ kent University Medical Faculty, Adana, Turkey S. Gu¨r Department of Radiology, S¸ ifa University Medical Faculty, Izmir, Turkey K. Gu¨rel Department of Radiology, Abant Izzet Baysal University Medical Faculty, Bolu, Turkey I˙. Cos¸ kun Department of Cardiovascular Surgery, Bas¸ kent University Medical Faculty, Adana, Turkey
were successfully treated with catheter-directed thrombolysis or anticoagulation therapy. Conclusion Endovascular treatment of the obstructive aortic disease using self-expanding stents was safe and effective, with high technical success and long-term patency. Thromboembolic complications were high even though direct stenting was considered protective for thromboembolism formation. Particularly for infrarenal aortic stenosis, it can be recommended as the first-line treatment option for patients with obstructive atherosclerotic aortic disease. Keywords Aorta Percutaneous transluminal angioplasty Stenosis Stent Thromboembolism
Introduction The infrarenal abdominal aorta and the iliac arteries are the most common sites affected by atherosclerosis in patients with ischemic peripheral atherosclerotic diseases. However, localized stenosis or even occlusion of the infrarenal aorta above the aortic bifurcation occurs relatively infrequently . Traditional treatments for stenosis or occlusion of the aorta include endarterectomy or bypass surgery, which may be associated with significant mortality and morbidity . Percutaneous transluminal angioplasty (PTA) with or without stent placement is accepted as a primary treatment or good alternative treatment to surgery for patients with significant stenosis and occlusions in the iliac, femoropopliteal, and infrapopliteal regions. Reports on endovascular treatment of atherosclerotic lesions of the abdominal aorta are rare, probably reflecting the rarity of the aortic disease. Two different patterns of atherosclerotic disease affect the infrarenal aorta . These patterns include localized lesions of the aortic bifurcation involving the lower part of
Author's personal copy ¨ nder et al.: Endovascular Treatment of Infrarenal Aortic Lesions H. O
the abdominal aorta and the common iliac arteries, either symmetric or not; and isolated lesions of the infrarenal aorta without involvement of the aortic bifurcation . The latter pattern of aortic occlusive disease is relatively rare. It occurs more frequently in women between the ages of 30–50 years who are heavy smokers . PTA has been proposed as an alternative to surgery, and several studies have demonstrated its safety and efficacy in localized stenosis of the distal infrarenal aorta as well as in lesions involving the aortic bifurcation . Stenting offers theoretic advantages over PTA, and its use has been established in several vascular beds, with an excellent patency rate [3, 4]. In the infrarenal aorta, however, only a small number of studies to date have evaluated the results of primary stenting for localized stenosis , whereas total aortic occlusions have been conventionally considered as a relative contraindication for endovascular therapy. The purpose of this study was to report our experience with 40 patients subjected to PTA or primary stenting for aortic occlusive disease, ranging from single infrarenal aortic stenosis to distal aortic occlusion with or without iliac artery obstruction.
Materials and Methods All patients who had endovascular treatment for isolated atherosclerotic obstructive disease of the distal abdominal aorta with or without iliac artery involvement between January 2005 and May 2011 were retrospectively analyzed. All patients were consecutively enrolled, were symptomatic and had severe ([50%) stenosis or occlusion of the distal aorta with or without iliac artery obstruction. Primary treatment modality was stent placement to the aorta with or without predilatation at the discretion of the operator. Patients under 18 years of age and who had aortic or iliac artery involvement for reasons other than atherosclerosis were excluded from the study. Total aortic occlusion, pregnancy, and allergy to iodinated contrast media were other exclusion criteria. Written informed consent was obtained from each patient after detailed explanation of the risks and benefits of the procedure. Atherosclerosis risk factors as well as preprocedural and postprocedural clinical symptoms, Rutherford classification, and postprocedural ankle-brachial index (ABI) scores were recorded. Diagnosis of the obstructive arterial disease was established with one or more of the following: color Doppler ultrasonography (CDUS), computed tomography (CT) angiography, or magnetic resonance angiography. The diagnosis was confirmed by digital subtraction angiography during the intervention. All procedures were performed in the angiography unit under local anesthesia supplemented with intravenous sedation and analgesia using Dormicum and fentanyl citrate. The
patients were monitored with pulse oximetry, electrocardiography, and blood pressure. Heparin was administered intraarterially at a dose of 5,000 IU after placement of a vascular sheath. Access to the artery was obtained with unilateral or bilateral common femoral artery puncture under ultrasonography guidance and diagnostic angiograms were obtained. If the aortic or iliac stenosis was not significant (\70% diameter stenosis) multiple projections of the aorta or the iliac arteries were obtained. If the lesion severity seemed similar, then intraarterial pressure measurements were made without flow augmentation. A pressure gradient of 10 mm Hg or more was accepted significant and treated with stenting. The aortic stenoses or occlusions were crossed with a 0.035 inch hydrophilic guide wire (Terumo, Tokyo) by retrograde approach. After crossing the obstruction, the obstructive lesion was either stented (direct stenting) without predilatation or predilated with a balloon and then stented (primary stenting). Patients with localized stenosis at the infrarenal aorta were treated with direct aortic stenting and patients with aortoiliac lesions were treated with direct stenting in case of stenoses, or primary stenting in the presence of occlusions. There were no selection criteria to use a selfexpanding or a balloon-expanding stent. Stents were bare selfexpanding nitinol or steel stents in the aorta (Wallstent, Boston Scientific, Galway, Ireland; or Protege, ev3, Plymouth, MN), and nitinol stents in the iliac arteries. Aortic stents were placed so that they would not limit future open repair, if needed. Therefore, proximal extent of the aortic stent was never extended up to the most distal renal artery origin. Stents were dilated with noncompliant balloon catheters (Ultra-Thin or Blue Max, Boston Scientific, Galway, Ireland). Self-expanding stents were oversized up to 10%. However, balloon catheters were not oversized. Stent sizing was based on the lumen diameter of the healthy aorta just proximal or distal to the lesion measured on the preprocedural angiogram. The stent length chosen was the shortest one appropriate for complete coverage of the lesion and adequate proximal and distal attachment to healthy aortic segments. At the end of the procedure, a completion angiogram was performed for demonstration of the final result and evaluation of distal embolization. Hemostasis was achieved by local manual pressure alone. After the procedure, a single antiplatelet treatment with aspirin (100 mg/d) was administered with instructions that this therapy be continued for life. Technical success was obtained if the residual stenosis as measured on the angiogram was B30%. Clinical success was defined as improvement in walking distance. Follow-up examinations were performed at 1, 6, and 12 months and then every year, with clinical and radiologic evaluations. Radiologic evaluation was performed by CDUS in all patients and CT angiography in selected patients. Patients were sent home the same day (6 h after the procedure) if no complication occurred.
Author's personal copy ¨ nder et al.: Endovascular Treatment of Infrarenal Aortic Lesions H. O
Data are expressed as mean ± standard deviation for continuous variables and percentages for categorical variables. Statistical analysis was performed using software (SPSS, version 16.0; SPSS, Chicago, IL). A chi-square test or Fisher’s exact test was used to compare categorical variables. Stent patency was estimated by using the Kaplan–Meier method. A P value of \0.05 was considered to be statistically significant.
Table 2 Comparison of isolated aortic lesions and aortoiliac lesions Characteristic
Group 1 (isolated aortic lesion)
Group 2 (aortoiliac lesion)
Mean age (year)
Sex, n (%) Male Female Complication rate, n (%)
Results Patient characteristics are summarized in Table 1. Most patients were male smokers with hypercholesterolemia. All patients had claudication, and none had critical limb ischemia. There were 40 patients (32 men, eight women) with a mean age of 59 years (range 44–77 years). Lesion length ranged 1–7 cm for the aorta and 3–9 cm for the aortoiliac lesions. All patients had [50% stenosis or occlusion of the aorta and the iliac artery or an intraarterial pressure gradient across the stenosis of 10 mm Hg or more. Arterial involvement was in the aorta in 18 patients (group 1) and in the aorta continuously extending to the iliac arteries in 22 patients (group 2) (Table 2). In group 1, six patients had lesions causing [50% diameter obstruction of the iliac arteries that were not continuous with the aorta (Fig. 1). In group 2, all lesions included aortic bifurcation. One lesion in each group was an occlusion, and the rest were stenosis. Iliac artery lesions were bilateral in 24 patients and unilateral in four patients. Stent diameter ranged 12–16 mm in the aorta and 7–10 mm in the iliac arteries. Lesion length Table 1 Population characteristics and preinterventional clinical classification Characteristic
Cardiovascular risk factors Smoking
Coronary heart disease
Chronic renal failure
Rutherford classification 1 (mild claudication)
2 (moderate claudication)
3 (severe claudication) 4–6 (critical limb ischemia)
25 (63%) 0
Mortality, n (%)
Rutherford category (n)
R3 Additional obstructive artery lesions (n)
covered by stents ranged 4–12 cm. Some of the patients had associated significant ([50%) stenosis or occlusion of the arteries in other vascular beds: superficial femoral artery (n = 2), common femoral artery (n = 2), popliteal artery (n = 2). Most of these lesions were also treated with PTA or stent placement at the same session. Six patients (15%) had a total of nine complications. Three patients developed a distal thromboembolism to the superficial femoral and popliteal arteries. Two of the patients were in group 1 and 1 patient was from group 2; all the stents placed were self-expanding. Three patients were treated successfully with thrombolysis at a dose of 1 mg/h for eight and 14 h. Another patient also had a very distal thromboembolism resulting in cyanosis of the third toe. Anticoagulation with low molecular weight heparin was initiated with resolution of ischemia in 1 week in this patient. Three patients with thromboembolisms had primary stent placement followed by PTA, whereas 1 patient with a popliteal thromboembolism had PTA followed by stent placement. Other complications included groin hematoma (n = 3), and pseudoaneurysm formation (n = 1), and local (1 cm length) aortic dissection that did not require treatment (n = 1). No procedure-related death occurred within 30 days after initial angioplasty, nor were there any aortic ruptures. Thirty-six patients were sent home the same day, and four patients who had occlusion of the aorta or the iliac artery were discharged after 1 to 4 days. Clinical and technical success was 100% in all patients after the procedure. Thirty-three patients experienced resolution and seven patients improvement of clinical symptoms after the procedure. Postprocedural ABI scores ranged 0.85–1.12, with mean ABI scores of 1.02 on the
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Fig. 1 A Digital subtraction angiography of the aortography in a 57-year-old man reveals a stent in the right common iliac artery that was placed 1 year ago (black arrow). Infrarenal aorta has diffuse
stenosis at the midportion (white arrow). B A balloon-expandable stent was successfully deployed in the aorta without residual stenosis
right and 0.96 on the left. There were no differences with respect to age, sex, lesion length, and stenosis ratio between group 1 and group 2 (P [ 0.05). Follow-up time ranged from 1 to 72 months (median 24 months). Seven patients died during follow-up. At follow-up, all patients had clinical evaluation, CDUS examination, and ABI score measurements. Eighteen patients had CT examinations with a multidetector CT (16 detector, GE, USA) at least once during follow up. The ABI score was within normal (0.9–1.1) in 21 patients out of 30 who had been on follow-up. Eight patients had ABI scores lower than 0.9 (0.74–0.86, mean 0.79) in only one limb, and 1 patient had ABI scores \0.9 for both limbs (0.74 on the right and 0.76 on the left). None of these patients had symptoms requiring endovascular intervention. At followup, all patients had patent stents without significant stenosis, as indicated by CDUS and clinical findings at a median follow-up of 24 months. Kaplan–Meier analysis revealed 100% primary patency rate at 1, 3, and 5 years. Long-term mortality was significantly higher in patients with isolated aortic lesions when compared to those who had aortoiliac lesions.
smaller-sized balloons, thus minimizing the risk of aortic rupture. Self-expanding stents may also trap atherothrombotic material more effectively owing to their smaller struts and theoretically reducing the possibility of distal embolization . However, in the current study, thromboembolism was observed in 4 patients, thereby disproving what was predicted from the self-expanding stents. Focal stenosis or occlusion of the infrarenal aorta is a relatively rare entity . It most commonly affects younger patients with less extensive atherosclerotic lesions compared with those who have iliofemoral or more distal diseases . Heavy smoking, elevated blood lipid concentrations, female gender, and hypoplastic aorta syndrome are considered among the most important risk factors [3, 9]. Hypoplastic aorta syndrome and focal short stenosis of the aorta has been described in relatively young (40–50 years) female smokers with high blood lipid levels. However, men predominated in our study. Prevalence of the male sex persisted in the isolated aortic stenosis group (group 1) as well as the aortoiliac stenosis group (group 2). Aortobifemoral bypass or aortic endarterectomy has been the traditional treatment of choice for infrarenal aortic occlusive disease with well-documented long-term results . In carefully selected patients, the 11 year cumulative patency rate after localized endarterectomy of the abdominal aorta is 86% , whereas long-term patency after aortobifemoral bypass is reported to be up to 90% at 5 years and 75% at 10 years . These procedures, however, are associated with significant morbidity and mortality  and may also lead to sexual dysfunction in up to one-third of men . PTA, which was initially introduced for aortic lesions in 1980 by Grollman et al. , Velasquez et al. , and Tegtmeyer et al. , has been proposed as an alternative to surgery. Since then, several studies have been published
Discussion In this study, we treated 40 patients who had obstructive atherosclerotic disease of the aorta with or without extension to the common iliac artery. A very high rate of technical and clinical success rates were observed and restenosis was not encountered during a median follow-up of 24 months. Self-expanding bare aortic stents were used in most of the patients in this study. These stents may achieve gradual expansion after balloon widening, allowing for the use of
Author's personal copy ¨ nder et al.: Endovascular Treatment of Infrarenal Aortic Lesions H. O
demonstrating successful results of PTA in localized stenosis involving the infrarenal aorta as well as the aortic bifurcation . Aortic PTA has a satisfactory immediate outcome, with initial technical success ranging 95–100% ; however, its midterm and long-term efficacy is frequently compromised as a result of restenosis . Stenting may overcome the suboptimal results of PTA; although, to our knowledge to date no prospective randomized trials have compared the two techniques. Stent implantation is theoretically superior to PTA because it provides a smooth cylindrical lumen that favors nonturbulent flow, thus minimizing the possibility of thrombus formation and subsequent aortic lumen restenosis . In addition, stenting reduces the recoil effect after PTA, especially in calcified ‘‘hard’’ aortic lesions, whereas the consequences of in-stent neointimal hyperplasia are not so crucial in a large diameter vessel such as the aorta. Unlike the iliofemoral territory, stenting has been infrequently documented in the infrarenal aorta. First, in 1990, Dietrich et al.  began to offer stent therapy to patients with abdominal aortic lesions that were considered to be at high risk for conventional surgery. In 24 patients, they reported a 100% cumulative primary patency at 5 years. Since then, a small number of series have studied the efficacy of stent placement in the infrarenal aorta. Technical success in these studies was 82–100%, whereas primary patency rates were 83–100% during the short-term and midterm follow-up [6–8, 18]. The current study revealed a high degree of technical success and long-term patency rates during a maximum follow up of 72 months. There were no stent thromboses or occlusions during the follow-up period. In most published studies, aortic stents were implanted after predilatation. In our study, however, 30 patients who had localized aortic stenosis were treated successfully with direct stenting without predilatation. Stenting without predilatation, though not clinically proven, may minimize the risk of vessel rupture by distributing the dilating forces more evenly against the aortic wall . No symptoms of mesenteric ischemia developed postoperatively in any of the patients in this series. Although one could argue that implantation of a stent across the inferior mesenteric artery (IMA) should be avoided, our experience revealed the opposite because patency of this artery is usually maintained despite enjailment of its ostium [19, 20]. Even if the IMA is occluded after stent placement it should be considered acceptable as long as the patient remains asymptomatic. The reasoning for this is because the IMA is commonly sacrificed as part of the procedure during aortic surgery. Stent covering of the IMA orifice should be avoided only in cases of superior mesenteric/ celiac artery occlusive disease, enlarged and meandering IMA, or bilateral hypogastric artery occlusion.
Wescott et al. reported in the STAR registry nearly the same results as in this study, but the treated mean lesion length was shorter ([1.6 cm) than in this series . Wescott et al. stated that PTA without stent placement should be the treatment of choice. In that study, the treated mean lesion length was 2 cm, while the treated mean lesion length in our study was 3.5 cm. Our preference of treatment for obstructive aortic lesions was stent placement, which has had good technical success and long-term patency to date. Although several large series in the literature report the outcome of PTA in obstructive aortic lesions, outcome of stent placement is not frequently reported [7, 18, 19, 22]. To our knowledge, this study is the largest study reporting the outcome of stent placement in obstructive aortic and aortoiliac artery lesions. Prospective randomized studies are necessary to definitively clarify this issue; however, because such evidence is not currently available, the decision regarding first endovascular treatment method or predilatation of the aorta before stent placement is based mainly on arbitrary data and physicians’ personal opinions. The study’s limitations include its retrospective nature and small patient population, which became more important when comparing isolated aortic lesions with aortoiliac lesions. Also, ABI measurements were not obtained before the procedure but obtained after the procedure during follow-up. There was no angiographic confirmation of patency of the stents; however, our protocol states to perform angiography only when endovascular treatment is planned. We did not see any objective or subjective evidence of recurrence at the treated vessels and therefore did not perform any endovascular intervention for any patients during follow-up. Our results support the feasibility, safety, and efficacy of primary stent placement with obstructive lesions of distal infrarenal aorta and aortoiliac bifurcation. Stent placement with or without predilatation, our preliminary findings along with that of other series indicate that stent placement may have a significant role in the management of the whole range of infrarenal aortic occlusive disease. Particularly for infrarenal aortic stenosis, it is recommended as the first-line treatment option, whereas for total aortoiliac occlusions, it should be considered as a reasonable alternative to surgery. Conflict of interest of interest.
The authors declare that they have no conflict
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