H Masuhara

The University of Tokyo, Tokyo, Tokyo-to, Japan

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Publications (8)0 Total impact

  • Article: [Staged surgical palliations for hypoplastic left heart syndrome with poor preoperative conditions].
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    ABSTRACT: A 2.8 kg-female newborn diagnosed as hypoplastic left heart syndrome was transferred to our hospital after resuscitation against systemic circulatory failure due to closure of the ductus arteriosus. Her systemic circulation was stabilized after alprostadil (lipo-PGE1) and inotorpic agent infusion along with mechanical ventilation support. On admission, signs of a pulmonary high-flow and low systemic perfusion were evident. Impaired coagulation aspect was gradually noted. Because a surgical palliation with cardiopulmonary bypass was considered to be at high-risk, a bilateral pulmonary artery banding was indicated. Through a median sternotomy, the right and left pulmonary arteries were individually banded. The patient was continued on the same ventilation strategy. Cardiac, hepatic and renal dysfunctions were improved over next few days and the patient weaned from ventilatory support. She underwent combined Norwood stage I and II repair at 4 months of age with weight of 4.8 kg. Postoperative course has been uneventful and the patient is now followed up in preparation for Fontan operation.
    Kyobu geka. The Japanese journal of thoracic surgery 01/2006; 58(13):1145-8.
  • Article: [Comparison of right ventricular function between prevention and enlargement of pulmonary valve annulus after repair of tetralogy of Fallot; mid-term results].
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    ABSTRACT: Total of 41 patients with tetralogy of Fallot (TOF) who underwent intracardiac repair from 1993 to 1998 were divided into 2 groups: preservation (n = 14) or enlargement (n = 27) of the pulmonary valve annulus. The procedure was decided on the Z value of the annular size: above or under -2 SD of the standard value. Although postoperative right ventricular (RV) diastolic volume (RVEDV) and cardiothoracic ratio (CTR) were larger than the preservation group and pulmonary regurgitation (PR) existed in the enlargement group, RV pressure was decreased and central venous pressure (CVP) was low and RV contraction was preserved. The exercise capacity was also good and no significant arrhythmia was recognized. Our mid-term results showed that appropriate enlargement of the pulmonary valve annulus preserved good RV function in patients with TOF.
    Kyobu geka. The Japanese journal of thoracic surgery 12/2005; 58(12):1049-52.
  • Article: [Differences in postoperative course by preoperative left ventricular volume after closure of ventricular septal defect during early infancy].
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    ABSTRACT: A total of 38 early infants with ventricular septal defect (VSD) were divided into 2 groups by preoperative LVEDV. The group A (n=14, LVEDV>250% N) showed significantly longer period of intubation, cathecholamine drip, and hospitalization compared with the group B (n=28, LVEDV<250% N). At dischage, both groups showed significant lowered right ventricular (RV) pressure, but LVSF in the group A was significantly lower than that in the group B. The patients with larger left ventricular (LV) volume preoperatively were thought to be potential high-risk groups in cardiac and pulmonary function and their postoperative course was prolonged and recovery of LV function was worse. In such patients, special care is mandatory to do postoperative management and to decide timing of operation.
    Kyobu geka. The Japanese journal of thoracic surgery 02/2005; 58(1):71-3.
  • Article: [Off-pump coronary artery bypass grafting for severe acute coronary syndrome].
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    ABSTRACT: Off-pump coronary artery bypass grafting (off-pump CABG: OPCAB) has become a standard procedure, but the indication for the patients with severe acute coronary syndrome (ACS) has not been established. The purpose of this study is to evaluate the role of OPCAB for patients with acute myocardial infarction (AMI) and impending myocardial infarction (IMI). Clinical indication of OPCAB for acute coronary syndrome between November 1997 and December 2002, 14 patients diagnosed ACS out of 220 CABG cases underwent surgery. Twelve male and 2 female with a mean age of 66.3 +/- 7.5 were NYHA grade IV condition before surgery. Three of nine AMI cases and 4 of 5 IMI cases underwent OPCAB. Thirteen cases needed intra-aortic balloon pumping (IABP) support pre-operation, in 1 AMI and 2 IMI cases IABP had to be weaned during operation. The mean graft number was 2.6. Except one AMI case with severe cardiac damage, 13 cases were discharged in NYHA grade I-II condition. CONCLUSION: In early onset cases with still rising CK-MB, operative risk and result is difficult to evaluate pre-operatively. Equal results could be seen in IMI cases with no previous myocardial damage. We suggest, that in cases without severe myocardial damage, OPCAB could be one alternative treatment.
    Kyobu geka. The Japanese journal of thoracic surgery 08/2003; 56(8 Suppl):678-81.
  • Article: Tuberculous abdominal aortic pseudoaneurysm penetrating the left psoas muscle after BCG therapy for bladder cancer.
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    ABSTRACT: We describe a case of a 75-year-old man with abdominal aortic and right femoral tuberculous pseudoaneurysms 32 months after intravesical bacillus Calmette-Guerin therapy for bladder cancer. These aneurysms were probably brought on by systemic infection by Mycobacterium bovis. The infrarenal aorta and right common femoral artery were successfully replaced with an in situ expanded polytetrafluoroethylene graft. Tuberculous pseudoaneurysm after bacillus Calmette-Guerin therapy for malignancy is very rare, and we review the related literature.
    Cardiovascular Surgery 07/2003; 11(3):231-5.
  • Source
    Conference Proceeding: Dynamic compilation of a reflective language using run-time specialization
    H. Masuhara, Y. Sugita, A. Yonezawa
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    ABSTRACT: In reflective languages, application programs can customize a language system that executes the application programs. Our premise is that this customizability of reflective languages can be a basic mechanism of software evolution. We present a simple architecture of a reflective language that can dynamically select meta-interpreters, and a dynamic compilation scheme by using run-time specialization (RTS) techniques, which could also be useful to dynamically optimize systems with mechanisms of dynamic software evolution. Our prototype system showed that dynamically compiled reflective programs run more than four times faster than the interpreted ones, and that compilation processes are fast enough to be invoked at runtime. Compared to statically compiled programs, however, dynamically compiled ones yet have 20-30% overheads. We also discuss this problem
    Principles of Software Evolution, 2000. Proceedings. International Symposium on; 02/2000
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    Article: Evaluation of Annuloaortic Ectasia by Angioscopy and IVUS "Report of 2 cases".
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    ABSTRACT: We attempted combined use of angioscopy and intravascular ultrasonography (IVUS) to localize the coronary ostia and determine the aortic segment to be replaced in patients with annuloaortic ectasia, because these preoperative informations are important for selection of an appropriate technique for reconstructing the coronary artery, to prevent complications, and also to postoperative follow-up. Two cases with annuloaortic ectasia underwent angioscopy and IVUS both pre- and post-operatively. Structure of aortic cusps, position of coronary ostia, the extent of ectasia with very thin wall were clearly observed by IVUS. Angioscopy showed milky white luminal surface of the ectasic segment. After Cabrol's operation, the sutured portion of native aorta and graft was clearly identified by IVUS and mural thrombus and naked surface of graft were observed by angioscopy. Complications were observed in none. The results indicate feasibility of combined use of angioscopy and IVUS for determination of surgical approach and follow-up in patients with AAE.
    Diagnostic and Therapeutic Endoscopy 02/2000; 7(1):35-45.
  • Article: [Reoperation of tetralogy of Fallot for the transannular patch neo-intimal stenosis: a case report].
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    ABSTRACT: A 3-year-old male patient underwent right ventricular outflow tract reconstruction with a glutaraldehyde-preserved equine pericardium for tetralogy of Fallot. Because of progressive severe pulmonary restenosis with over systemic right ventricular pressure, tricuspid regurgitation, and abnormal high echoic shadow in the distal main pulmonary artery on echocardiogram, he required reoperation a year after the first correction. In the reoperative findings, the pseudointima was thickened heavily and detached from glutaraldehyde-preserved equine pericardial patch. The patch was removed and the right ventricular outflow was reconstructed widely to the pulmonary bifurcation with porcine pericardial patch again. Patho-histological findings showed foreign body giant cells and macrophages in the pseudointima. Four years after the reoperation, echocardiogram shows 41 mmHg for the right ventricular pressure and 22 mmHg for the pressure gradient of right ventricular outflow tract, and the patient is doing well now.
    Kyobu geka. The Japanese journal of thoracic surgery 10/1999; 52(10):856-9.