Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Hiroyuki Morokuma is active.

Publication


Featured researches published by Hiroyuki Morokuma.


Journal of Vascular Surgery | 2014

Operative technique for tracheo-innominate artery fistula repair

Kojiro Furukawa; Keiji Kamohara; Manabu Itoh; Hiroyuki Morokuma; Shigeki Morita

Tracheo-innominate artery fistula is fatal unless treated surgically. We describe our surgical approach and results in seven patients. The average patient age was 15.7 years; all patients had prior severe neurological deficits. Three of seven patients were in hemorrhagic shock; control of preoperative bleeding was achieved with tracheostomy tube cuff overinflation. The innominate artery and the trachea were exposed through a collar incision and partial upper sternotomy. The innominate artery was divided at the aortic arch and at the bifurcation, with one exception. Cerebral blood flow was monitored by the blood pressure difference in the bilateral upper extremities and by near-infrared spectroscopy. The tracheal fistula was left adherent to the innominate artery in all but one patient. All patients were discharged without new neurologic deficits or severe morbidity. Overall survival was 84% at 37 months, without any vascular, tracheal, or neurological events.


The Annals of Thoracic Surgery | 2015

Surgical Strategy for Retrograde Type A Aortic Dissection Based on Long-Term Outcomes

Keiji Kamohara; Kojiro Furukawa; Shugo Koga; Junji Yunoki; Hiroyuki Morokuma; Ryo Noguchi; Kojiro Takase; Atsuhisa Tanaka; Shigeki Morita

BACKGROUND The optimal management of a retrograde type A aortic dissection (RAAD) is controversial, and few reports have discussed the long-term outcomes of surgical strategies. To determine the most appropriate strategy, we studied the early and late outcomes of RAAD cases. METHODS From 1998 to 2014, 44 patients with RAAD (mean age of 63 ± 11 years) underwent surgical repair. Ascending aortic replacement (AAR) was performed in 21 patients and ascending and total arch replacement (TAR) was performed in 23 patients. Eight of the patients who received TAR underwent complete resection of the primary tear in the distal arch or descending aorta (TAR-R[+]), whereas the remaining 15 patients received elephant trunk implantation as an alternative procedure for tear resection (TAR-R[-]). The early and late outcomes (mean follow-up, 86.5 months) were evaluated. RESULTS Hospital mortality occurred in 4 of the 44 (9.1%) patients, with no mortalities among the patients undergoing TAR-R[-]. There was a tendency toward a higher incidence of late aorta-related events in the AAR group, with a significantly higher patency rate of the false lumen in the proximal site of the residual aorta compared with the TAR group (p = 0.009). Furthermore, the 5-year rate of freedom from aortic growth greater than 50 mm was significantly lower after AAR than after TAR (p = 0.04). A multivariate analysis indicated that the initial ascending aortic diameter (odds ratio [OR], 1.5; p = 0.02) and AAR (OR, 29.1; p = 0.01) were independent predictors of late aortic expansion. CONCLUSIONS The surgical outcomes were acceptable in both the AAR and TAR groups. The long-term outcomes potentially support the aggressive adoption of TAR in relatively younger patients with significant ascending aortic enlargement at presentation.


The Annals of Thoracic Surgery | 2008

Preoperative Evaluation of the Right Gastroepiploic Artery on Multidetector Computed Tomography in Coronary Artery Bypass Graft Surgery

Keiji Kamohara; Naoki Minato; Noritoshi Minematsu; Junji Yunoki; Takeshi Hakuba; Hisashi Satoh; Hiroyuki Morokuma; Yuichi Takao

BACKGROUND The right gastroepiploic artery (GEA) is commonly used in coronary artery bypass grafting, but a method for preoperative assessment of the suitability of the GEA has not been established. Here, we assessed the efficacy of 64-slice multidetector computed tomography (MDCT) for this purpose. METHODS Multidetector computed tomography was performed for 32 patients (24 males, 8 females; mean age, 65.9 +/- 7.4 years) undergoing coronary artery bypass graft surgery. Preoperative MDCT criteria for GEA suitability were no significant stenosis or calcification and a diameter of 2.0 mm or more in the middle portion of the GEA. The skeletonized GEA was inspected in 30 patients to determine the accuracy of evaluation of arteriosclerosis by MDCT (2 patients were excluded owing to severe GEA stenosis). The internal diameter at the anastomotic site was compared with the diameters of the proximal, distal, and middle regions of the GEA on MDCT. RESULTS The GEA was used to bypass a target coronary artery in 30 patients. The diameter of the middle of the GEA on MDCT correlated strongly with the actual internal diameter at the anastomotic site (r = 0.72, p < 0.0001). The diameter at the anastomotic site calculated from MDCT using the distance from the GEA origin to the anastomotic site and the actual diameter did not differ significantly (2.76 +/- 0.6 versus 2.87 +/- 0.5 mm, p = 0.06). CONCLUSIONS Preoperative MDCT imaging of the GEA is reliable for diagnosis, and a middle diameter of 2.0 mm or greater can be used to indicate GEA suitability for coronary artery bypass grafting.


Annals of Thoracic and Cardiovascular Surgery | 2014

Extensive resection and double-patch reconstruction for left atrial myxoma.

Hiroyuki Morokuma; Yuji Katayama; Keiji Kamohara; Noritoshi Minematsu; Shugo Koga

The efficacy and safety of surgical intervention for atrial myxoma are established, but the operative approach to tumor resection and atrial reconstruction are controversial. A biatrial approach is generally used for excision of atrial myxoma and has many advantages. In contrast, there are a few reports about the method of double-patch reconstruction, and the right and left atrium are individually reconstructed with the two patches. We found it to be effective in the case reported here. We suggest that this method can be applied to atrial myxoma in which extensive resection is necessary.


Journal of Cardiac Surgery | 2010

Partial Aortic Root Remodeling with an Adventitial Inversion Technique for an Acute Type A Aortic Dissection

Junji Yunoki; Yoshihiro Nakayama; Hiroyuki Oonishi; Hiroyuki Morokuma; Hideya Tanaka

Abstract  This case report describes a partial aortic root remodeling, which applied a valve‐sparing technique, with an adventitial inversion technique for an acute type A aortic dissection with intimal tear extending into the noncoronary sinus of Valsalva. Postoperative computed tomography at six months showed no dissection or pseudoaneurysm in the aortic root. (J Card Surg 2010;25:327‐329)


Annals of Thoracic and Cardiovascular Surgery | 2010

Three Surgical Cases of Isolated Tricuspid Valve Infective Endocarditis

Hiroyuki Morokuma; Naoki Minato; Keiji Kamohara; Noritoshi Minematsu


The Japanese Journal of Thoracic and Cardiovascular Surgery | 2017

Should the annulus be fixed in aortic valve-sparing root replacement with remodeling?

Kojiro Furukawa; Keiji Kamohara; Junji Yunoki; Shugo Koga; Manabu Itoh; Hiroyuki Morokuma; Yosuke Mukae; Tsuyoshi Itoh; Shigeki Morita


Japanese Journal of Cardiovascular Surgery | 2016

A Case of Central Diabetes Insipidus Who Underwent Open Heart Surgery

Shizuka Yaita; Ryo Noguchi; Keiji Kamohara; Junji Yunoki; Hiroyuki Morokuma; Shugou Koga; Atuhisa Tanaka; Koujiro Furukawa; Shigeki Morita


Jpn. J. Vasc. Surg. | 2015

Two Cases of Traumatic Popliteal Artery Injury

Nagi Hayashi; Kojiro Furukawa; Hiroyuki Morokuma; Manabu Itoh; Keiji Kamohara; Shigeki Morita


Japanese Journal of Cardiovascular Surgery | 2015

Resection of Myxoma in the Acute Phase of Hemorrhagic Cerebral Infarction

Hideya Tanaka; Kojiro Furukawa; Hiroyuki Morokuma; Ryo Noguchi; Manabu Itoh; Keiji Kamohara; Shigeki Morita

Collaboration


Dive into the Hiroyuki Morokuma's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge