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Featured researches published by Toru Iwahashi.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2010

Long-term results of second-stage thoracic endovascular aortic repair following total aortic arch replacement

Yukio Obitsu; Nobusato Koizumi; Yasunori Iida; Toru Iwahashi; Naozumi Saiki; Hisahito Takae; Satoshi Kawaguchi; Hiroshi Shigematsu

PurposeWe investigated the surgical results of secondary thoracic endovascular aneurysm repair (TEVAR) using the elephant trunk graft after total aortic arch replacement (TAR) for extensive thoracic aortic lesions.MethodsThe subjects comprised 16 patients who underwent TEVAR as a staged procedure following TAR at our institution between 1997 and 2007. Long-term results were retrospectively surveyed (mean observation period 68.4 months). We performed TEVAR with the elephant trunk graft as a proximal landing zone for the descending thoracic repair, the mean duration between TAR and TEVAR was 4.7 weeks for the staged operations and 18.3 months for the nonstaged operations.ResultsEarly results were good in all cases, with no deaths and no noteworthy complications. For the seven patients without dissection, long-term results were also good. Among the nine patients with dissection, the false lumen in the thoracoabdominal area enlarged in three during follow-up. We performed thoracoabdominal repair in two, but one died of an aneurysm-esophageal fistula. There was only one long-term aneurysm-related death.ConclusionSecond-stage TEVAR using the elephant trunk graft after TAR allows less invasive surgery for extensive aortic lesions and achieves good long-term results. However, enlargement of the false lumen was a long-term concern in patients with aortic dissection, and careful follow-up is essential.


Annals of Vascular Diseases | 2013

Endovascular stent graft repair for thoracic aortic aneurysms: the history and the present in Japan.

Satoshi Kawaguchi; Hideyuki Shimizu; Akihiro Yoshitake; Taro Shimazaki; Toru Iwahashi; Hitoshi Ogino; Shin Ishimaru; Hiroshi Shigematsu; Ryohei Yozu

Stent-grafts for endovascular repair of thoracic aortic aneurysms have been commercially available for more than ten years in the West, whereas, in Japan, a manufactured stent-graft was not approved for the use until March 2008. Nevertheless, endovascular thoracic intervention began to be performed in Japan in the early 1990s, with homemade devices used in most cases. Many researchers have continued to develop their homemade devices. We have participated in joint design and assessment efforts with a stent-graft manufacturer, focusing primarily on fenestrated stent-grafts used in repairs at the distal arch, a site especially prone to aneurysm. In March 2008, TAG (W.L. Gore & Associates, Inc., Flagstaff, Arizona, USA) was approved as a stent graft for the thoracic area first in Japan, which was major turning point in treatment for thoracic aortic aneurysms. Subsequently, TALENT (Medtronic, Inc., Minneapolis, Minnesota, USA) was approved in May 2009, and TX2 (COOK MEDICAL Inc., Bloomington, Indiana, USA) in March 2011. Valiant as an improved version of TALENT was approved in November 2011, and TX2 Proform as an improved version of TX2 began to be supplied in October 2012. These stent grafts are excellent devices that showed good results in Western countries, and marked effectiveness can be expected by making the most of the characteristics of each device. A clinical trial in Japan on Najuta (tentative name) (Kawasumi Labo., Inc., Tokyo, Japan) as a line-up of fenestrated stent grafts that can be applied to distal arch aneurysms showing a high incidence, and allow maintenance of blood flow to the arch vessel was initiated. This trial was completed, and Najuta has just been approved in January of 2013 in Japan, and further development is expected. In the U.S., great efforts have recently been made to develop and manufacture excellent stent grafts for thoracic aneurysms, and rapid progress has been achieved. In particular, in the area of the aortic arch, in which we often experience aneurysmal change, but there are no commercially available devices which are urgently needed. Companies are competing keenly to develop devices. To our knowledge, more than 4 manufacturers are involved in the development of functionally new stent grafts in this area. The introduction of branched stent grafts may not be faraway.


Journal of Cardiothoracic Surgery | 2010

Surgical repair for aortic dissection accompanying a right-sided aortic arch

Yukio Obitsu; Nobusato Koizumi; Toru Iwahashi; Naozumi Saiki; Hiroshi Shigematsu

Aortic anomaly in which a right-sided aortic arch associated with Kommerells diverticulum and aberrant left subclavian artery is rare. The present report describes a patient with type-B aortic dissection accompanying aortic anomalies consisting of right-sided aortic arch and the left common carotid and left subclavian artery arising from Kommerells diverticulum. As dissecting aortic aneurysm diameter increased rapidly, Single-stage surgical repair of extensive thoracic aorta was performed through median sternotomy and right posterolateral fifth intercostal thoracotomy, yielding favorable results. Our surgical procedures are discussed.


Journal of Cardiology Cases | 2012

Bilateral coronary ostial stenosis and aortic regurgitation in a patient with cardiovascular syphilis

Katsuhiko Matsuyama; Masahiko Kuinose; Yasunari Iida; Toru Iwahashi; Katsutoshi Sato; Tomoaki Iwasaki; Nobusato Koizumi; Toshiya Nishibe; Hitoshi Ogino

Cardiovascular syphilis is associated with the tertiary stage of syphilis infection; it involves the ascending aorta and can cause aortic aneurysm, aortic regurgitation, and coronary ostial stenosis. We report a surgical case of bilateral coronary ostial lesion and aortic regurgitation due to syphilitic aortitis. <Learning objective: Syphilitic aortitis involves the ascending aorta, resulting in aortic aneurysm, aortic regurgitation, and coronary ostial stenosis. Unlike atherosclerosis, coronary ostial stenosis is caused by aortic wall thickening, and coronary lesions distal to the ostia occur only rarely. After surgery, long-term follow up is mandatory as a result of aortic dilatation involving the sinuses of Valsalva, occurrence of prosthetic valve dehiscence, or graft failure caused by continuous infection of the aortic wall.>.


The Thoracic & Cardiovascular Surgeon Reports | 2014

A Rare Case of Dacron Graft Rupture due to Friction against a Rib

Katsuhiko Matsuyama; Masahiko Kuinose; Nobusato Koizumi; Toru Iwahashi; Kayo Toguchi; Hitoshi Ogino

A 54-year-old man underwent aortic repair for the infected thoracoabdominal aneurysm with a woven Dacron graft (Vascutek, Renfrewshire, Scotland) treated with gentian violet. Four months later, he complained of sudden back pain, resulting in preshock status. Computed tomographic scans showed massive hematoma around the Dacron graft, suggesting graft rupture. Initially, emergency thoracic endovascular aortic repair was performed, which was subsequently followed by open repair. The Dacron graft had a small hole, which was completely compatible with the site contacting with the rib. The graft rupture was considered due to its friction against the rib. We report on a rare event of mechanical Dacron graft rupture after the thoracoabdominal aortic replacement.


Annals of Vascular Diseases | 2011

Conservative Therapy for Surgically Untreatable Extensive Arteriovenous Malformation from the Lower Extremityto the Pelvis with Secondary Consumptive Coagulopathy

Toru Iwahashi; Naozumi Saiki; Nobusato Koizumi; Toshiya Nishibe; Hitoshi Ogino

We present a woman with surgically untreatable extended arteriovenous malformations (AVM) and consumptive coagulopathy, which had been controlled by conservative compression and anticoagulation therapies for 17 years. At age 13, she was diagnosed with extended AVM in the entire left leg and pelvis. At age 16, limited surgical resection of the enlarged superficial vein in the left calf was performed for persistent leg pain. One year later, anticoagulation therapy was performed for massive bleeding from hemorrhoids due to AVM and coagulopathy. Despite its intractability, her condition has been favorably controlled with conservative methods, including compression and anticoagulation therapies.


Journal of Cardiology Cases | 2014

Successful treatment using percutaneous drainage for aortic arch prosthetic graft infection

Katsuhiko Matsuyama; Masahiko Kuinose; Nobusato Koizumi; Noriaki Iwasaki; Toru Iwahashi; Kayo Toguchi; Hitoshi Ogino

Prosthetic graft infection in the ascending aorta or aortic arch is a life-threatening complication. Redo graft replacement is also associated with high mortality and morbidity rates. Conservative treatments without graft removal recently developed as alternatives to conventional surgical approach have been reported with successful outcomes. We report a case of successful treatment of prosthetic graft infection in the aortic arch, for which percutaneous catheter drainage was initially performed prior to open surgery, followed by graft coverage with an omental flap. <Learning objective: Redo graft replacement for the prosthetic graft infection in the ascending aorta or aortic arch is associated with high mortality and morbidity rates. Conservative treatments without graft removal have recently been developed as alternatives to surgical approaches. Less invasive percutaneous drainage and irrigation would be a useful alternative second-line treatment before radical open repairs for the treatment of aortic graft infection.>.


The Annals of Thoracic Surgery | 2013

Apicoaortic Valved Conduit Bypass for Progressing Aortic Graft Stenosis Due to Malformation of Repeated Thoracic Endovascular Aortic Repairs

Yasunori Iida; Nobusato Koizumi; Katsuhiko Matsuyama; Toru Iwahashi; Hitoshi Ogino

Since the first report by Cooley and colleagues in 1975 [Cooley DA, Norman JC, Mullins CE, Grace R. Left ventricle to abdominal aorta conduit for relief of aortic stenosis. Cardiovasc Dis 1975;2:376-83], an apicoaortic valved conduit bypass has been usually administrated to selected patients presenting with certain clinical conditions or complications such as aortic stenosis associated with porcelain aorta, unclampable atherosclerotic aorta, resternotomy, or previous coronary bypass surgery. On the other hand, thoracic endovascular aortic repair for various aortic lesions has become a promising and less invasive therapy. We encountered a critical case of a patient suffering from aortic graft stenosis due to malformation of a previous thoracic endovascular aortic repair procedure originally performed for acute type A aortic dissection. Because of a deep sternal wound infection, apicoaortic valved conduit bypass from the left ventricular apex to the abdominal aorta was successfully performed.


Annals of Vascular Surgery | 2011

Intraoperative Evaluation of Blood Perfusion by Laser-Assisted Indocyanine Green Angiography After ex vivo Vascular Reconstruction of Intrahilar Renal Artery Aneurysm

Toru Iwahashi; Yukio Obitsu; Nobusato Koizumi; Naozumi Saiki; Satoshi Takahashi; Hiroshi Shigematsu

The surgical reconstruction of intrahilar renal artery aneurysms (RAAs) is a difficult surgery because of complex anatomy. We present a case of right intrahilar RAA diagnosed in a 67-year-old man. We performed ex vivo reconstruction using an organ preservation solution to prevent postoperative renal failure. We assessed graft patency and blood perfusion was assessed by laser-assisted indocyanine green angiography using the SPY system after autotransplantation. Postoperative renal insufficiency was not observed. The results demonstrate that ex vivo reconstruction of intrahilar RAAs using an organ preservation solution, and graft patency and blood perfusion evaluation using the SPY system are effective methods for preserving renal function.


International Angiology | 2016

Two-year outcome of the Endurant stent graft for endovascular abdominal aortic repair in Japanese patients: incidence of endoleak and aneurysm sac shrinkage.

Toshiya Nishibe; Toru Iwahashi; Kamiya K; Toguchi K; Maruno K; Fujiyoshi T; Muromachi Y; Suzuki S; Koizumi J; Ogino H

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Hitoshi Ogino

Tokyo Medical University

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Yukio Obitsu

Tokyo Medical University

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Naozumi Saiki

Tokyo Medical University

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Kayo Toguchi

Tokyo Medical University

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