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Dive into the research topics where Hidetaka Wakiyama is active.

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Featured researches published by Hidetaka Wakiyama.


Angiology | 1999

Usefulness of cardiopulmonary bypass in reconstruction of inferior vena cava occupied by renal cell carcinoma tumor thrombus

Chojiro Yamashita; Takasi Azami; Morihito Okada; Yoshiya Toyoda; Hidetaka Wakiyama; Masato Yoshida; Keiji Ataka; M. Okada

Aggressive surgical treatment in renal cell carcinoma is still controversial. The aim of this paper is to assess inferior vena caval (IVC) reconstruction for suprahepatic vena caval renal cell carcinoma (RCC) tumor thrombus. Twelve patients with suprahepatic vena caval thrombus from renal cell carcinoma who underwent surgical repair with cardiopulmonary bypass were evaluated. The vena caval defect was reconstructed by direct suture, patch repair, or graft replacement. Of 12 patients undergoing partial cardiopulmonary bypass, tumor thrombus extended to the junction of the hepatic vein in three patients and to the right atrium in one. Tumor thrombus was removed manually or with balloon catheter. Tumor thrombus in the right atrium was removed during electrical ventricular fibrillation. Repair of the IVC was performed by direct suture of the IVC wall in two patients, patch repair with expanded polytetrafluoroethylene (EPTFE) graft in seven, and graft replacement with an EPTFE graft in three. There were no operative deaths and the only postoperative complication was one patient death from pulmonary emboli. The four patients with nonlocalized disease died within 2 years, but four patients lived for more than 3 years postoperatively. Survival was 37.5% at 3 years and 18.8% at 5 years by the Kaplan-Meiers method. Conclusions: (1) Partial cardiopulmonary bypass is useful for the control of bleeding when tumor thrombus in the IVC extends to the junction of the hepatic vein. (2) Nephrectomy with tumor thrombectomy of the IVC is valuable, and long-term survival is possible in patients without distant metastases or regional lymph node metastases.


The Annals of Thoracic Surgery | 1997

Open Distal Anastomosis in Retrograde Cerebral Perfusion for Repair of Ascending Aortic Dissection

Chojiro Yamashita; Masayoshi Okada; Keiji Ataka; Masato Yoshida; Naoki Yoshimura; Takashi Azami; Keitarou Nakagiri; Hidetaka Wakiyama; Teruo Yamashita

BACKGROUNDnIn patients with aortic dissection, a patent distal false lumen at long-term follow-up leads to complications. We investigated the feasibility of performing an open distal anastomosis using retrograde cerebral perfusion.nnnMETHODSnOver a 10-year period, 41 patients with acute type A aortic dissection underwent 43 surgical repairs. In 1991, an open distal anastomosis using retrograde cerebral perfusion (group 2) was introduced to replace the standard aortic cross-clamp method (group 1). The mean retrograde cerebral perfusion time was 47.3 minutes (range, 22 to 67 minutes), and there were no neurologic sequelae in surviving patients.nnnRESULTSnThe operative mortality rate was 18.5% in group 1 and 18.7% in group 2. At long-term follow-up, dilatation of the false lumen (more than 50 mm in diameter) occurred in 9 of 18 patients (50%) in group 1, and 2 patients died of aortic rupture. There were no deaths in group 2, and dilatation of the distal false lumen occurred in only 15.4% of patients (p < 0.05).nnnCONCLUSIONSnThe use of retrograde cerebral perfusion in patients with acute aortic dissection provides adequate time to perform a safe, open, distal anastomosis, and could decrease significantly the rate of enlarged, patent, false lumina.


Surgery Today | 2000

Tension Hemothorax Caused by a Ruptured Aneurysm of the Descending Thoracic Aorta : Report of a Case

Yoshio Ootaki; Masayoshi Okada; Chojiro Yamashita; Takaki Sugimoto; Hidetaka Wakiyama

The rupture of an aneurysm of the descending thoracic aorta into the right thoracic cavity is a comparatively rare event, and it is very difficult to establish a diagnosis immediately and rescue such patients. We describe herein the successful surgical treatment of a patient with this life-threatening emergency by initiating immediate cardiopulmonary bypass. It is mandatory to drain the right thoracic bleeding through a left thoracotomy without delay to release the tension hemothorax. Furthermore, it is necessary to evacuate the right thoracic hematoma through a right thoracotomy, because complete removal of a huge hematoma through a left thoracotomy cannot be effectively achieved.


The Annals of Thoracic Surgery | 1998

Impact of retrograde cerebral perfusion with posterolateral thoracotomy on distal arch aneurysm repair.

Chojiro Yamashita; Masayoshi Okada; Tosiki Yoshimura; Takasi Azami; Keitarou Nakagiri; Hidetaka Wakiyama; Keiji Ataka

BACKGROUNDnRepair of distal aortic arch aneurysms is difficult to accomplish through a median sternotomy or left thoracotomy, and stroke and respiratory disorders often become lethal complications with the use of circulatory arrest. We investigated the use of retrograde cerebral perfusion with a posterolateral thoracotomy in the repair of distal arch aneurysms.nnnMETHODSnThirty-eight patients underwent repair of a distal arch aneurysm. They were divided into three groups according to the method of surgical repair used. Sixteen patients (group I) underwent proximal anastomosis of the graft with the use of an aortic cross-clamp. Eight patients (group II) underwent open proximal anastomosis with the use of retrograde cerebral perfusion (oxygenated blood perfusion through a superior vena cava cannula) and a median sternotomy and anterolateral thoracotomy. Fourteen patients (group III) also underwent open anastomosis with the use of retrograde cerebral perfusion (cerebral perfusion through blood returned to the right atrium with the patient in the Trendelenburg position) and a posterolateral thoracotomy.nnnRESULTSnThe operative mortality rate in group I was 25.0%; 4 of 16 patients died of stroke, myocardial infarction, and intestinal necrosis. In group II, 3 of 8 patients (37.5%) died of respiratory failure and aortic dissection. In group III, only 1 of 14 patients (7.1%) died, as a result of heart failure.nnnCONCLUSIONSnThe use of retrograde cerebral perfusion with a posterolateral thoracotomy is an alternative method that minimizes the risk of stroke and respiratory failure during distal aortic arch operations.


Surgery Today | 1998

Successful surgical treatment of an Edwards type IIIB right aortic arch aneurysm: Report of a case

Hidetaka Wakiyama; Masayoshi Okada; Chojiro Yamashita; Keitaro Nakagiri; Naoki Yoshimura; Masato Yoshida; Keiji Ataka; Takaki Sugimoto

A true aneurysm of the right aortic arch which accompanies various branching characteristics is very rare. We report herein the successful surgical treatment of an elderly patient found to have an Edwards type IIIB right aortic arch aneurysm encircling and compressing the trachea. The complete right aortic arch and right subclavian artery were reconstructed through the inside of the aneurysm using selective cerebral perfusion. The patient recovered well, with no residual neurologic deficit and with resolution of the dyspnoic attacks he had suffered preoperatively.


The Japanese Journal of Thoracic and Cardiovascular Surgery | 1999

Valvular heart disease. A comparative study of results after primary operation, reoperation, and after multiple reoperation.

Keiji Ataka; Masayoshi Okada; Chojiro Yamashita; Teruo Yamashita; Hidetaka Wakiyama; Keitaro Nakagiri; Naoki Yoshimura

Reoperation for valvular heart disease has been associated with a higher operative mortality than primary operations, especially in patients who had multiple prior operations. We have analyzed the 226 consecutive patients who underwent valve replacement. These involved 163 primary operations, 52 first reoperation, and 11 second/third reoperations. Preoperative left ventricular dysfunction was more severe, and operation time and cardiopulmonary bypass time were significantly greater according to the number of operations, associated with a greater amount of intraoperative blood loss. The operative mortality after a second/third reoperation was 27.3%, which was significantly higher than that after primary operation (6.7%) (p < 0.05), and that after first reoperation (5.8%) (p < 0.05). Seven (64%) patients who underwent a second/third reoperation had poor preoperative left ventricular function (%FS < 25%), and 5 (71%) of these required postoperative mechanical supports, and 3 (60%) of the 5 patients died of low output syndrome. We have found that poor preoperative left ventricular function and the duration on cardiopulmonary bypass, but not the number of reoperation were correlated with operative mortality. Continued efforts should be directed to decrease the mortality for multiple reoperative valve surgery.


Artificial Organs | 1999

Usefulness of Postoperative Percutaneous Cardiopulmonary Support Using a Centrifugal Pump: Retrospective Analysis of Complications

Chojiro Yamashita; Keiji Ataka; Takashi Azami; Keitarou Nakagiri; Hidetaka Wakiyama; Masayoshi Okada


The Kobe journal of the medical sciences | 1998

Hepatic microcirculation during transient hepatic venous occlusion--intravital microscopic observation using hepatic vein clamp model in the mouse.

Chojiro Yamashita; Hidetaka Wakiyama; Masayoshi Okada; Nakao K


The Kobe journal of the medical sciences | 1997

INCREASED PORTAL ENDOTHELIN-1 LEVEL IS ASSOCIATED WITH THE LIVER FUNCTION AFTER CARDIOPULMONARY BYPASS IN RABBITS : INFLUENCE OF HYPOTHERMIA ON THE DAMAGE

Hidetaka Wakiyama; Chojiro Yamashita; Masayoshi Okada; Maeda H


The Kobe journal of the medical sciences | 1998

Results of surgical treatment for thoracoabdominal aneurysm using cardiopulmonary bypass under moderate hypothermia and selective visceral artery perfusion.

Chojiro Yamashita; Keiji Ataka; Yoshida M; Takaki Sugimoto; Hidetaka Wakiyama; Masayoshi Okada

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Keiji Ataka

Boston Children's Hospital

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Keiji Ataka

Boston Children's Hospital

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