Jpn J Intervent Radiol Vol.27 No.2 2012

State of the Art
Technical Tips for EVAR and TEVAR

An Introduction  
Junichiro Sanada
Department of Radiology, Kanazawa University

1. Tips and Trouble Shooting in Endovascular Aneurysm Repair

Department of Radiology, National Cerebral and Cardiovascular Center
Tetsuya Fukuda

Endovascular aortic aneurysm repair (EVAR) has revolutionized the treatment of abdominal aortic aneurysms. Successful endovascular exclusion of abdominal aortic aneurysms is dependent on formation of a seal between the endoprosthesis and the nonaneurysmal aorta. Recommendations for suitability of EVAR have focused on preoperative anatomic characteristics of the proximal landing zone such as the length of the neck and angulation. Type I and III endoleaks require prompt, definitive repair or explantation. In addition, occlusion of the renal artery during the procedure or follow up period may affect the prognosis of the patients. However, the presence of the transrenal stent struts could make access to the renal artery for secondary intervention difficult or impossible. We review and report our experience of endovascular management of type I endoleaks and renal artery occlusion during the EVAR procedure and follow-up period.

Key words

  • EVAR
  • Challenging neck

2. Technical Tips in Endovascular Repair of Aortic Diseases

Department of Radiology, Mie University Hospital
Noriyuki Kato, Shuji Chino, Mikito Inouchi, Takashi Hashimoto, Takatoshi Higashigawa

Endovascular repair with stent-grafts is now the first line therapy for aortic diseases. In 2011, more than half of patients with abdominal aortic aneurysms underwent endovascular repair in Japan. Endovascular repair is also preferred for the treatment of patients with thoracic aortic diseases. In addition to the fact it has become widely known to patients and physicians, the development of innovative devices leading to an increase of suitable patients for endovascular therapy seems to have contributed to widespread application of this therapy. However, there remain limitations with currently available devices. A variety of technical tips are introduced to overcome the difficulties in this article.

Key words

  • Stent−graft
  • Endovascular therapy
  • Aorta

3. Technical Tips for Endovascular Repair for Thoracic Aortic Aneurysm: TEVAR

Department of Radiology and Cardiovascular Surgery1) Oita University, Faculty of Medicine
Norio Hongo, Shinji Miyamoto1), Rieko Shuto, Noritaka Kamei
Tomoyuki Wada1), Satomi Ide, Shunro Matsumoto, Hiro Kiyosue, Hiromu Mori

Aneurysms of the thoracic aorta are a life-threatening disease. While open aortic repair has been a standard procedure, thoracic endovascular aortic repair (TEVAR) has gained acceptance as an alternative for high-risk patients. The recent release of the PMDA-approved stent-grafts for thoracic aortic aneurysms has facilitated the widespread use of TEVAR in Japan because of its lower mortality and morbidity based on its lower invasiveness. Furthermore, hybrid TEVAR for aortic arch aneurysms or thoracoabdominal aortic aneurysms expands the treatment choices for patients. We describe here some particular technical tips in terms of avoiding unfavorable events such as endoleak and distal embolism. We also discuss advanced techniques such as TEVAR for aortic dissection and in-situ fenestration with case presentation.

Key words

  • Stent-graft
  • Endovascular
  • Thoracic aortic aneurysms

4. Technical Tips in EVAR -Gore Excluder Deployment Techniques and Tips

Deparment of Radiology and Faculty of Medical Science1) and Cardiovascular Surgery2), Fujita Health University
Tatsuo Banno, Ryoichi Kato1), Ryota Hanaoka, Hokuto Akamatsu, Yoshihiro Sanda
Kazuhiro Katada, Kan Kaneko2), Hiroshi Kondo2), Motomi Ando2)

In recent EVAR procedures, non-IFU cases are also being performed. In EVAR, proximal neck fixation is the most important point in every case. This article shows several techniques and tips of trying EVAR in difficult short neck and angled neck cases, especially in Gore Excluder®.
Endowedge techniques (EWT) including non-sheath assisted, EWT with sheath assisted manners are presented.
Scrum technique is a special technique that is only feasible in Gore Excluder®. The name is derived from rugby’s scrummage. By pushing from both sides of a pull through guide wire, the proximal portion of the stentgraft is bent. This technique is applicable in very angled neck cases.
Scrum with Endowege technique is a more precise deployment in short and angle neck cases. In shaggy aorta cases guide wires and stentgraft dialator have the risk of thrombo-embolic complications, and in this case wire-bending technique is applied. This manner reduces thromboembolism from a shaggy descending aorta.
Kilt technique is also a special technique for dumb-bell shape of infra-renal neck configuration. Also troublesome cases include limb occlusion caused by weak points in Excluder® body and legs. The very rare complication of stentgraft collapse is also presented.

Key words

  • EVAR
  • Aortic stent−graft
  • Excluder

5. Technical Tips and Troubleshooting for Challenging EVAR (Endovascular Aneurysm Repair) Cases

Department of Radiology, Nara Medical University
Shigeo Ichihashi, Hirofumi Itoh, Masahide Takahashi, Shinsaku Maeda
Tetsuya Masada, Shinichi Iwakoshi, Kimihiko Kichikawa
Department of Radiology, Okinawa Prefectural Chubu Hospital
Wataru Higashiura
Department of Aortic Stentgraft and Endovascular Therapy, Matsubara Tokushukai Hospital
Shoji Sakaguchi
Department of Radiology and IVR center, Daiyukai General Hospital
Hideo Uchida

After the Zenith stentgraft was approved in Japan in 2006, a large number of EVARs (Endovascular aneurysm repairs) have been performed across Japan. Many physicians have obtained wide experience and advanced their skills, and so outside IFU (Instruction for use) cases are now also treated by EVAR. Useful techniques for overcoming challenging anatomy for EVAR are introduced in this article. These techniques include PTA (percutaneous transluminal angioplasty) and internal endoconduit for narrow iliac access, brachio-femoral wire for tortuous iliac access, and slow deployment for angulated proximal neck. This article describes some AAA (abdominal aortic aneurysm) cases with complicated anatomy, which were successfully treated by EVAR with these ancillary endovascular techniques. In addition, bailout techniques for device related complications are briefly discussed.

Key words

  • EVAR
  • PTA
  • Tug of wire
  • Complication

6. Technical Tips for Stent Graft Treatment

Department of Diagnostic Radiology and Cardiovascular Surgery1), Tenri Hospital
Takanori Taniguchi, Kensuke Uotani, Naoaki Kusunoki, Hirotaka Tomimatsu, Gosuke Okubo
Akiko Kawasaki, Naoto Katayama, Yusuke Yokota, Tsuyoshi Suga, Nobuyuki Mori
Yuko Nishimoto, Satoshi Noma, Takeshi Nishina1), Daisuke Nakatsuka1), Kazuo Yamanaka1)

Since the advent of a commercially available stent graft (Zenith AAA Endovascular Graft) in 2007, endovascular stent graft treatment for thoracic aortic aneurysm and abdominal aortic aneurysm (TEVAR and EVAR) has expanded rapidly in Japan, and TEVAR and EVAR are now major options of aortic repair comparable with open surgical repair. Since 2007, over 250 patients have undergone TEVAR and EVAR in our hospital and indications have increased year by year. The majority of cases were treated by the usual method, but several special techniques were necessary for unusual cases such as outsiders of Instruction for Use. In this article, we introduce some special techniques for TEVAR and EVAR based on our experiences.

Key words

  • Aneurysm
  • Stent Graft
  • TEVAR and EVAR
  • Technical Tips

7. Technical Tips in Iliac Artery Intervention for Stent Grafting

Department of Radiology, Aichi Medical University
Tsuneo Ishiguchi, Toyohiro Ota, Seiji Kamei, Makiyo Hagihara
Yuichiro Izumi, Akira Kitagawa, Shuji Ikeda

Abdominal aortic aneurysm is often associated with aneurysmal dilatation of the common iliac arteries. Iliac artery interventions including coil embolization of internal iliac artery play important roles in endovascular aneurysm repair (EVAR). Also, for treatment of common iliac artery aneurysms, stent-grafting is one of the major treatments with or without coil embolization. In this chapter, technical tips for iliac interventions relevant to stent grafting are described. Use of a guiding sheath and coaxial microcatheter system, detachable fibered microcoils followed by pushable coils, liquid glue mixed with Lipiodol, optimal working angle for identification of the arterial branches and radiation protection for patients and operators are essential. Buttock claudication and erectile dysfunction are frequent complications of internal iliac artery embolization. Occlusion of the proximal internal iliac arterial trunk will be associated with reduced complications compared with distal occlusions. Though not currently approved in Japan, branched endovascular graft preserves blood flow to the internal iliac artery, reducing the potential for ischemic sequelae.

Key words

  • Hypogastric artery
  • Embolization
  • Aneurysm
  • Aortic aneurysm

8. Technical Tips about the Device Insertion in Thoracic Endovascular Aortic Repair (TEVAR)

Department of Radiology and Cardiovascular Surgery1), Matsubara Tokushukai Hospital
Shoji Sakaguchi, Akinori Kojima1), Reo Sakakura1), Tsuyoshi Yoshida1)
Department of Cardiovascular Surgery, Yao Tokushukai Hospital
Yasuhiko Kobayashi, Yoshinaka Nakao, Hiroshi Irie, Haruhiko Akagi
Department of Radiology, Nara Medical University
Masahide Takahashi, Shigeo Ichihashi, Shinichi Iwakoshi
Hirofumi Itoh, Wataru Higashiura, Kimihiko Kichikawa

The first clinical endovascular aortic repair (EVAR) of a traumatic chest descending aorta was reported by Volodos in 1988. Although thoracic endovascular aortic repair (TEVAR) looks comparatively simple as an interventional procedure, according to the spatial relationship of aneurysm and aortic arch branches, aortic tortuosity and quality of aortic-wall plaque, it is difficult to carry out with low invasiveness without complications. Knowledge of many different approach techniques and various experiences are required to perform the procedure safely.
We present some difficult TEVAR cases from the viewpoint of device insertion, and explain some technical tips.

Key words

  • TIPS
  • Pull-through

Original Article

Preoperative CT Imaging Analyzed Using a 3D Workstation before PSE to Predict Embolization Volume

Department of Radiology, National Hospital Organization Oita Medical Hospital
Kazufumi Kikuchi, Yusuke Nakamura, Masaaki Yoshimoto, Toshiyoshi Katahira
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University
Yoshiki Asayama

In partial splenic embolization (PSE), the embolized volume rate is a critical factor affecting both efficacy and complications. The aim of this study was to investigate the reliability of CT imaging analyzed using a 3D workstation before PSE to predict the embolization volume. We analyzed the relationships between the splenic artery diameter and post-PSE embolization volume. Pearson’s product-moment correlation was 0.56, which represents a moderate correlation. Our results demonstrated that CT imaging analyzed using a 3D workstation before PSE might be useful for predicting the preoperative embolization volume.

Key words

  • Partial splenic embolization (PSE)
  • Workstation
  • Splenic infarction percentage

Case Reports

Traumatic Pseudoaneurysm of the Transverse Facial Artery Treated by Transarterial Embolization with a 1.5Fr. Marathon Microcatheter, an ED Coil and N-butyl Cyanoacrylate -A Case Report-

Department of Radiology and Neurosurgery1), Hamamatsu University School of Medicine
Mika Kamiya, Shuhei Yamashita, Hisaya Hiramatsu1), Harumi Sakahara

We report a patient with a pseudoaneurysm of a transverse facial artery that was treated by transarterial embolization. A 50-year-old female, following an alcohol induced fall, developed a massive hematoma in her right buccal area. The next day, she was admitted to our hospital. Computed tomography revealed a large subcutaneous hematoma in her right buccal area. Enhanced computed tomography also revealed extravasation of contrast medium from a peripheral branch of the right transverse facial artery. Transarterial embolization was performed. We introduced a 1.5Fr. Marathon microcatheter into the right transverse facial artery more distally. First, we occluded a tiny branch to the skin with an ED coil-10, and then occluded the pseudoaneurysm and proximal portion of the artery with N-butyl cyanoacrylate (NBCA). The final external carotid angiogram revealed no pseudoaneurysm. The 1.5Fr. Marathon microcatheter was very useful because the vessel had a small diameter, and deployment of an ED coil was necessary.

Key words

  • Traumatic facial artery pseudoaneurysm
  • NBCA
  • ED coil

Case Reports

Pulmonary Artery Stent Implantation for Advanced Lung Cancer Combined with Superior Vena Cava Stenting: A Case Report

Department of Radiology, Saitama Medical Center Jichi Medical University
Tomohisa Okochi, Katsuhiko Matsuura, Kohhei Hamamoto, Sumiko Tsunoda
Hidekazu Tsunoda, Keisuke Tanno, Yoshio Ohmori, Osamu Tanaka
Department of Diagnostic Radiology, Saitama Cancer Center
Yoshihiro Tochigi

We report a woman in her 70s with far advanced lung cancer, complaining of facial edema and severe dyspnea. Computed tomography revealed complete obstruction of the superior vena cava (SVC) and severe right pulmonary artery (RPA) stenosis due to huge mediastinal and right hilar tumors. To palliate her severe symptoms, we selected simultaneous SVC and RPA stent placements. We considered the risk of left pulmonary congestion due to increased venous return after SVC-stent implantation, which was the reason for simultaneous stents being placed in both the SVC and RPA. A self-expandable stent (LUMINEXX 12mm×40mm) was placed in the RPA via the right femoral approach after pre-dilatation with a 6-mm balloon. Following this procedure, spiral Z-stents (20mm×80mm, 20mm×60mm) were placed from the left innominate vein to the SVC using a pull-through technique after pre-dilatation with a 6-mm balloon. There were no apparent complications; the severe symptoms disappeared immediately after these interventions. Simultaneous placement of both SVC and RPA stents has not been reported previously. Our case suggested the clinical efficacy, as palliative treatment, of simultaneous stent implantation in malignant conditions with severe stenosis of both the SVC and RPA.

Key words

  • Stent placement
  • Superior vena cava syndrome
  • Pulmonary artery stenosis

Case Reports

Coil Embolization of Giant Splenic Artery Aneurysm with Coil Anchor Technique Using PDA Coil

Department of Radiology, Kagoshima University Graduate School of Medical and Dental Sciences
Sadao Hayashi, Yasutaka Baba, Terutoshi Senokuchi
Shunichiro Ikeda, Kouhei Nagasato, Masayuki Nakajo
Department of Surgery1) and Rediology2), Kagoshima Kouseiren Hospital
Shigeho Maenohara1), Ichiro Kanetsuki2)

We report a case of successful coil embolization of an ostial type giant splenic artery aneurysm using the coil anchor technique. A 5-cm aneurysm was pointed out in the abdomen by screening ultrasonography in a man in his late 70s. It was later proven to be a splenic artery aneurysm by contrast enhanced abdominal CT. He was referred to us for embolotherapy of the aneurysm, which was located at the splenic artery 1 cm distal to its branching-off point from the celiac artery. It seemed difficult to embolize the afferent artery of the aneurysm by the usual isolation technique because the afferent artery was too short to deploy microcoils safely without risk of migration, and the aneurysm was too large to be packed by microcoils alone. Therefore, after coil embolization of the efferent artery, we used a 0.035 inch detachable patent ductus arteriosus (PDA) coil as a coil anchor for safe deployment of additional 0.018 inch microcoils. This technique resulted in safe deployment of both types of coil in the afferent artery without their migration into the celiac trunk and aneurismal sac. Thus this coil anchor technique with a PDA coil may be useful for successful isolation of a visceral aneurysm whose target vessel is too short to be safely embolized by the usual isolation technique.

Key words

  • PDA coil
  • Splenic artery aneurysm
  • Embolization