Network


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

Hotspot


Dive into the research topics where Katsuhiro Yamanaka is active.

Publication


Featured researches published by Katsuhiro Yamanaka.


The Journal of Thoracic and Cardiovascular Surgery | 2016

Early and late outcomes of repaired acute DeBakey type I aortic dissection after graft replacement

Atsushi Omura; Shunsuke Miyahara; Katsuhiro Yamanaka; Toshihito Sakamoto; Masamichi Matsumori; Kenji Okada; Yutaka Okita

OBJECTIVE The present study aimed to determine the impact of the extent of graft replacement on early and late outcomes in acute DeBakey type I aortic dissection. METHODS Between October 1999 and July 2014, 197 consecutive patients were surgically treated for acute DeBakey type I aortic dissection. The extent of graft replacement (hemiarch, partial, or total arch replacement) was mainly determined by the location of the primary entry. Early and late results were compared in patients after total arch replacement (n = 88) and combined hemiarch and partial arch replacement: non-total arch replacement (n = 109). RESULTS The in-hospital mortality rates of the total arch replacement and non-total arch replacement groups were 10.2% and 14.7%, respectively (P = .47). Multivariate analysis revealed preoperative cardiopulmonary resuscitation and visceral organ malperfusion as significant risk factors for in-hospital mortality, but not total arch replacement. During a mean follow-up period of 60 ± 48 months, the 5-year survivals in the total arch replacement and non-total arch replacement groups were 88.6% ± 4.2% and 83.8% ± 4.4%, respectively (P = .54). Rates of distal aortic events (defined as freedom from surgery for distal aorta dilation or distal arch diameter expanding to 50 mm) at 5 years were significantly better in the total arch replacement group than in the non-total arch replacement group (94.9% ± 3.5% vs 83.6% ± 4.9%, P = .01). CONCLUSIONS The operative mortality of patients with acute DeBakey type I aortic dissection treated by total arch replacement was acceptable with good long-term survival after both total arch replacement and non-total arch replacement. The frequency of distal aortic events might be reduced in patients after total arch replacement compared with non-total arch replacement.


European Journal of Cardio-Thoracic Surgery | 2014

Strategies for the treatment of aorto-oesophageal fistula

Yutaka Okita; Katsuhiro Yamanaka; Kenji Okada; Masamichi Matsumori; Takeshi Inoue; Keigo Fukase; Toshihito Sakamoto; Shunsuke Miyahara; Tomonori Shirasaka; Naoto Izawa; Taimi Ohara; Yoshikatsu Nomura; Hidekazu Nakai; Yasuko Gotake; Hiroya Kano

OBJECTIVES Presenting a surgical strategy for aorto-oesophageal fistula (AEF). METHODS From October 1999 to August 2013, 16 patients with AEF were treated at Kobe University Hospital. The mean age was 65.5 ± 10.2 years, and the male/female ratio was 13/3. Eight patients had non-dissecting thoracic aneurysm, 3 had chronic aortic dissection, 5 had oesophageal cancer and 1 had fish bone penetration. Five patients were in shock. Four patients had previous thoracic endovascular aortic repair (TEVAR) in the descending aorta and 1 had hemi-arch replacement. As treatment for AEF, 8 patients underwent TEVAR, 2 had a bridge TEVAR to open surgery, 2 had extra-anatomical bypass (EAB) and 5 had in situ reconstruction of the descending aorta. The oesophagus was resected in 8 patients, and an omental flap was installed in 7 patients. For the 4 most recent cases, simultaneous resection of the aorta and oesophagus, in situ reconstruction of the descending aorta using rifampicin-soaked Dacron graft and omental flap installation were performed. RESULTS Hospital mortality was noted in 4 patients (25.0%; persistent sepsis n = 3 and pneumonia n = 1). However, since 2007, only 1 of 5 patients died (pneumonia). All patients with oesophageal cancer died during follow-up. Two patients underwent oesophageal reconstruction using a pedicled colon graft and one is on the waiting list for oesophageal reconstruction. CONCLUSIONS Bridging TEVAR is a useful adjunct in treating AEF patients with shock. One-stage surgery consisting of resection of the aneurysm and oesophagus, in situ reconstruction of the descending aorta and omental flap installation provided a better outcome in the AEF surgical strategy compared with conservative treatment.


The Annals of Thoracic Surgery | 2015

Mid-Term Results of Valve-Sparing Aortic Root Replacement in Patients With Expanded Indications

Shunsuke Miyahara; Takashi Matsueda; Naoto Izawa; Katsuhiro Yamanaka; Toshihito Sakamoto; Yoshikatsu Nomura; Naoto Morimoto; Takeshi Inoue; Masamichi Matsumori; Kenji Okada; Yutaka Okita

BACKGROUND The mid-term results of valve-sparing aortic root reimplantation (VSRR) for various indications were investigated. METHODS From 2000 to 2013, 183 consecutive patients undergoing VSRR were enrolled. Expanded indications, defined as a patient on the marginal operative indication, included age 65 years or older (n = 33), age 15 years or younger (n = 4), acute type A aortic dissection (AAAD) (n = 21), aortitis (n = 8), reoperative root replacement (n = 11), cusp prolapse (n = 67), large aortoventricular junction of greater than 28 mm (AVJ) (n = 42), preoperative severe aortic regurgitation (AR) (n = 89), left ventricular ejection fraction 0.40 or less (n = 12), LV dilation (n = 66), New York Heart Association class III or greater (n = 5), need for total arch replacement (n = 29), and concomitant mitral valve repair (n = 12). RESULTS The overall survival at 5 years was 96.6%. Freedom from greater than mild AR and reoperation at 5 years was 85.8% and 92.9%, respectively. Cox proportional hazard model revealed that AAAD, cusp prolapse, AVJ 28 mm or greater, and operation before 2009 were at risk for late AR recurrence (p = 0.015, p = 0.0041, p = 0.032, and p = 0.014, respectively). After 2009, freedom from late AR in the cusp prolapse group improved (p = 0.055, versus control). Both freedom from recurrent AR and reoperation were worse as the number of expanded indications increased (log-rank trend p = 0.00017 and p = 0.00067, respectively). CONCLUSIONS Surgical outcomes of VSRR in these patient cohorts were satisfactory with some room for improvement in patients with cusp prolapse. Although the indications for VSRR are being expanded, a larger number of expanded indications were associated with poor outcomes in terms of longevity of valve function.


The Journal of Thoracic and Cardiovascular Surgery | 2013

Successful surgical treatment of aortoesophageal fistula after emergency thoracic endovascular aortic repair: Aggressive débridement including esophageal resection and extended aortic replacement

Hiroshi Munakata; Katsuhiro Yamanaka; Kenji Okada; Yutaka Okita

RESULTS From 2006 to 2012, this technique was used in 15 patients, mean age 72 years, 67% female. There were no strokes, but there were 3 in-hospital deaths, none directly related to the operative technique. One patient died on postoperative day 2 of mesenteric ischemia, another on postoperative day 24 of multisystem organ failure, and the third on postoperative day 72 of severe respiratory failure.


European Journal of Cardio-Thoracic Surgery | 2014

Surgical strategy for aorta-related infection

Katsuhiro Yamanaka; Atsushi Omura; Yoshikatsu Nomura; Shunsuke Miyahara; Tomonori Shirasaka; Toshihihito Sakamoto; Takeshi Inoue; Masamichi Matsumori; Hitoshi Minami; Kenji Okada; Yutaka Okita

OBJECTIVES This report describes our experience with surgical management of aorta-related infections. METHODS From November 1999 to April 2013, 70 patients underwent surgical management for aorta-related infection, including aortobronchial fistula in 12 patients, aorto-oesophageal fistula in 14 and aortoduodenal fistula in 4. The location of infection was aortic root to arch in 22 patients, descending aorta in 29, thoraco-abdominal aorta in 12 and abdominal aorta in 7. Forty-seven patients had infections of the native aorta and 23 had postoperative graft infections. In situ replacement [bridge thoracic endovascular aortic repair (TEVAR); n = 1] was performed in 45 patients, endovascular aortic repair in 18 and extra-anatomical bypass (bridge TEVAR; n = 2) in 7. Omental flap was installed in 29 patients and a pedicled latissimus dorsi muscle flap was used in 3. Since 2008, we have been trying to resect not only the infected tissues, but also the surrounding aneurysmal wall as well. RESULTS Hospital mortality was 17.1% (12/70). Late death occurred in 15 patients. Overall survival at 3 years was 60.1 ± 6.7%. Freedom from infection-related death of patients who had in situ graft replacement, endovascular repair or extra-anatomical bypass at 3 years was 88.5 ± 4.9, 75.2 ± 10.9 or 14.3 ± 13.2%, respectively (P < 0.01). In situ graft replacement provided a better freedom from aortic event (recurrent infection and reintervention) at 3 years compared with endovascular repair (85.6 ± 5.5 vs 61.8 ± 12.5%, P = 0.029). Freedom from infection-related death at 3 years improved significantly from 61.1 ± 9.7 (before 2008) to 84.7 ± 5.8% (since 2008) (P = 0.044). CONCLUSIONS Surgical treatment for aorta-related infection is still associated with high mortality and morbidity. However, our current strategy, which is aggressive surgical management, including resection of infected tissues, extensive debridement, in situ graft replacement of the aorta and omental or muscle installation provided a better patient survival.


The Journal of Thoracic and Cardiovascular Surgery | 2014

Early patency rate and fate of reattached intercostal arteries after repair of thoracoabdominal aortic aneurysms

Atsushi Omura; Katsuhiro Yamanaka; Shunsuke Miyahara; Toshihito Sakamoto; Takeshi Inoue; Kenji Okada; Yutaka Okita

OBJECTIVES The present study analyzes the early patency of intercostal artery reconstruction, using graft interposition and aortic patch anastomosis, and determines the fate of reattached intercostal arteries after repair of thoracoabdominal aortic aneurysms. METHODS We selected 115 patients (mean age, 63 ± 15 years; range, 19-83 years; male, n = 83) treated by thoracoabdominal aortic aneurysm repair with 1 or more reconstructed intercostal arteries at the Kobe University Graduate School of Medicine between October 1999 and December 2012. The intercostal arteries were reconstructed using graft interposition (n = 66), aortic patch anastomosis (n = 42), or both (n = 7). RESULTS The hospital mortality rate was 7.8% (n = 9). Eleven patients (9.6%) developed spinal cord ischemic injury (permanent, n = 6, transient, n = 5). The average number of reconstructed intercostal arteries per patient was 3.0 ± 1.5 (1-7), and 345 intercostal arteries were reattached. The overall patency rate was 74.2% (256/345) and that of aortic patch anastomosis was significantly better than that of graft interposition (90.8% [109/120] vs 65.3% [147/225], P < .01), but significantly worse for patients with than without spinal cord ischemic injury (51.9% [14/27] vs 76.1% [242/318], P = .01). There was no patch aneurysm in graft interposition during a mean of 49 ± 38 (range, 2-147) postoperative months, but aortic patch anastomosis including 4 intercostal arteries became dilated in 2 patients. CONCLUSIONS Aortic patch anastomosis might offer better patency rates and prevent spinal cord ischemic injury compared with graft interposition. Although aneurysmal changes in intercostal artery reconstructions are rare, large blocks of aortic wall reconstruction should be closely monitored.


The Annals of Thoracic Surgery | 2015

Influences of Chronic Obstructive Pulmonary Disease on Outcomes of Total Arch Replacement

Shunsuke Miyahara; Hidekazu Nakai; Naoto Izawa; Katsuhiro Yamanaka; Toshihito Sakamoto; Yoshikatsu Nomura; Takeshi Inoue; Masamichi Matsumori; Kenji Okada; Yutaka Okita

BACKGROUND Although an association between chronic obstructive pulmonary disease (COPD) and adverse surgical outcomes has been proposed, the impact of COPD severity on postoperative outcomes remains unclear. Our objective was to analyze the prognostic implication of COPD severity on outcomes after total aortic arch replacement. METHODS Between October 1999 and December 2012, 269 patients undergoing total arch replacement through median sternotomy, who were elective cases with preoperative spirometry records, were retrospectively reviewed. Patients were divided into four groups: control group, with ratio of forced expiratory volume of air in 1 second (FEV1) to forced vital capacity (FVC) of 70% or greater; mild airflow obstruction, with FEV1/FVC ratio less than 70% and FEV1 80% or greater of predicted; moderate airflow obstruction, FEV1/FVC ratio less than 70% and FEV1 50% to 79% of predicted; severe airflow obstruction, FEV1/FVC ratio less than 70% and FEV1 less than 50% of predicted. Symptoms of functional dyspnea and disability were also assessed. Multivariate logistic and Cox regression methods were used to determine if there was an independent association between COPD and short-term and long-term outcomes, respectively. RESULTS The in-hospital mortality rate was 2.2% (6 of 269). A consistent trend of increasing frequency of postoperative respiratory complications with advanced airflow obstruction was noted. In multivariate analysis, in-hospital mortality (p = 0.022), incidence of respiratory complications (p = 0.021) and overall mortality (p = 0.025) was significantly associated with the symptoms of COPD, respectively. CONCLUSIONS The severity of COPD as defined by spirometry and symptoms of functional dyspnea may be an important prognostic marker of patients undergoing total arch replacement.


Annals of cardiothoracic surgery | 2013

Surgical techniques of total arch replacement using selective antegrade cerebral perfusion

Yutaka Okita; Kenji Okada; Atsushi Omura; Hiroya Kano; Hitoshi Minami; Takeshi Inoue; Toshihito Sakamoto; Shunsuke Miyahara; Tomonori Shirasaka; Katsuhiro Yamanaka; Taimi Ohara; Yoshikatsu Nomura; Hidekazu Nakai

This detailed illustrated article describes our preferred surgical technique of total arch replacement using selective antegrade cerebral perfusion (SACP). Our current approach includes: (I) meticulous selection of arterial cannulation site and type of arterial cannula; (II) SACP for neuro-protection; (III) whole body hypothermia with minimal tympanic temperatures between 20 and 23 °C and minimal rectal temperatures below 30 °C; (IV) early re-warming after distal anastomosis with SACP flow adjustment while monitoring brain oxygenation by near infrared spectroscopy (NIRS); and (V) after 2006, maintaining strict fluid balance below 1 L by the extracorporeal ultrafiltration method (ECUM) during cardiopulmonary bypass (CPB), with the expectation of more rapid pulmonary functional recovery.


The Annals of Thoracic Surgery | 2012

Short and Midterm Outcomes of Elective Total Aortic Arch Replacement Combined With Coronary Artery Bypass Grafting

Kenji Okada; Atsushi Omura; Hiroya Kano; Taimi Ohara; Tomonori Shirasaka; Katsuhiro Yamanaka; Shunsuke Miyahara; Toshihito Sakamoto; Akiko Tanaka; Takeshi Inoue; Takanori Oka; Hitoshi Minami; Yutaka Okita

BACKGROUND This study was performed to investigate the early and late outcomes of total aortic arch replacement (TAR) with or without coronary artery bypass grafting (CABG). METHODS From October 1999 to December 2010, 200 consecutive patients underwent elective TAR for nondissecting aneurysm through a median sternotomy. Of this number, 131 (65.5%) had isolated TAR (TAR group) and 69 (34.5%) underwent concomitant CABG (TAR/CABG group). Patients in the TAR/CABG group were older and had more advanced chronic kidney disease and higher additive/logistic European System for Cardiac Operative Risk Evaluation and Japan scores than patients in the TAR group. RESULTS Overall 30-day mortality was 0.5% (1 of 200) and hospital mortality was 3.5% (7 of 200). Hospital mortality was 1.5% (2 of 131) in the TAR group and 7.2% (5 of 69) in the TAR/CABG group (p=0.036). Multivariate analysis showed that operation time (odds ratio [OR] 1.01, p=0.013) was a risk factor for hospital mortality, but failed to demonstrate concomitant CABG as a risk factor. Cox proportional hazard analysis showed that age (OR 1.08, p=0.05), female sex (OR 3.58, p=0.0004), chronic kidney disease (OR 7.70, p<0.0001), and operation time (OR 1.01, p=0.0002) were risk factors for midterm mortality, whereas concomitant CABG was not (OR 0.92, p=0.87). There was a significant difference in midterm survival and freedom from major cerebrocardiovascular events in the TAR group versus the TAR/CABG group. CONCLUSIONS Concomitant CABG was not a risk factor for hospital morality with TAR. However, patients with concomitant CABG have more preoperative comorbidities, which may adversely affect outcomes, and which may therefore deserve special attention.


Annals of cardiothoracic surgery | 2013

Total arch replacement using selective antegrade cerebral perfusion as the neuroprotection strategy

Yutaka Okita; Kenji Okada; Atsushi Omura; Hiroya Kano; Hitoshi Minami; Takeshi Inoue; Toshihito Sakamoto; Shunsuke Miyahara; Tomonori Shirasaka; Katsuhiro Yamanaka; Taimi Ohara; Yoshikatsu Nomura; Hidekazu Nakai

BACKGROUND Optimal neuro-protection strategy in aortic arch surgery is a controversial issue. The present study reported surgical outcomes of total arch replacement using selective antegrade cerebral perfusion (SACP). METHODS From January 2002 to December 2012, 438 consecutive patients (mean age 69.1±13.4 years) underwent total arch replacement using SACP through a median sternotomy. Acute aortic dissection was present in 86 patients (18.3; 80 type A, 6 type B) and shaggy aorta in 36 (8.2%). Emergent/urgent surgery was required in 144 (32.9%). Our current approach included: (I) meticulous selection of arterial cannulation site and type of arterial cannula; (II) selective antegrade cerebral perfusion; (III) maintenance of minimal tympanic temperature between 20 and 23 °C; (IV) early re-warming after distal anastomosis; and (V) maintaining fluid balance below 1,000 mL during cardiopulmonary bypass. A woven Dacron four branch graft was used in all patients. RESULTS Overall hospital mortality was 4.6% (20/438). Hospital mortality was 9.7% (14/144) in urgent/emergent surgery and 2.0% (6/294) in elective cases. Permanent neurological deficit occurred in 5.3% (23/438) of patients. Prolonged ventilation was necessary in 58 patients (13.2%). Multivariate analysis demonstrated that risk factors for hospital mortality were octogenarian (OR 4.45, P=0.03), brain malperfusion (OR 23.52, P=0.002) and cardiopulmonary bypass time (OR 1.07, P=0.04). The follow-up was completed in 97.9% with mean follow up of 2.3±2.3 years. Survival at 5 and 10 years after surgery was 79.6±3.3% and 71.2±5.0% respectively. In the acute type A dissection group, 10-year survival was 96.8±2.9%, while in the elective non-dissection group 5- and 10-year survival were 81.4±7.2% and 77.0±5.9% respectively. CONCLUSIONS Our current approach for total aortic arch replacement utilizing SACP was associated with low hospital mortality and morbidities leading to favorable long-term outcome.

Collaboration


Dive into the Katsuhiro Yamanaka'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

Hiroshi Tanaka

Tokyo Medical and Dental University

View shared research outputs
Researchain Logo
Decentralizing Knowledge