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J Nishizawa

Publications and source records attributed to J Nishizawa.

At least 19 recordsLinked to original sources
PubMed2004

Nasal mask bilevel positive airway pressure ventilation for diaphragmatic paralysis after pediatric open-heart surgery.

A 2-year-old boy underwent surgical repair of tetralogy of Fallot. Topical cooling of the heart with ice slush was used during the operation. Diaphragmatic paralysis occurred after the operation, inducing severe respiratory distress. To avoid repeated intubation and tracheostomy, the patient was placed on nasal mask bilevel positive airway pressure (BiPAP) ventilation. After ventilatory support with BiPAP for 40 days, the patient recovered spontaneously from the paralysis. No sedation was required during this time. This report illustrates the usefulness of BiPAP for a pediatric patient with diaphragmatic paralysis after cardiac surgery.

Child, Preschool↗
PubMed2004

[Management for type A acute dissection].

From March 1998 to May 2002, we experienced 46 patients with type A acute dissection (AAD). Fifteen patients managed initially with conservative treatment because of intramular hematoma (IH, n = 10), broad cerebral infarction (n = 3), others (n = 2). One who diagnosed IH at admission progressed to AAD and underwent surgery. However his diagnosis of IH at admission was proved to be misdiagnosis retrospectively. In 8 of the remaining 9 patients, hematoma disappeared during the follow-up of 6 months to 1 year. In patients with broad cerebral infarction, 2 died early after admission and 1 discharged with hemiplegia. Thirty-two patients underwent surgery and 1 with preoperative broad cerebral infarction died 36 days after surgery. In the remaining 31 patients, 30 patients discharged ambulatory.

Acute Disease↗
PubMed2004

[Early and late results of combined valvular and coronary artery surgery].

A total of 42 patients with combined valvular and coronary artery surgery were examined to analyze risk factors for cardiac related events and late deaths. There were aortic valve disease in 26 patients and mitral valve disease in 16. Preoperatively, 14 patients (33%) had cardiac dysfunction (ejection fraction < or = 40%) and 10 patients (24%) were in New York Heart Association (NYHA) functional class IV. There was no operative death with 96% of early graft patency. There was 8 late deaths during 5.6 years of mean follow up. Actuarial survival rate was 86% and 64% after 5 and 10 years, respectively. Cardiac dysfunction was a significant independent predictor for late death. Cardiac related events occurred in 9 patients. Freedom from cardiac related events was 78% and 59% after 5 and 10 years, respectively. Cardiac dysfunction and mitral valve surgery were significant independent predictors for cardiac related events. Late result of combined mitral and coronary artery surgery was unfavorable in patients with cardiac dysfunction.

Aged↗
PubMed2001

Coronary artery bypass grafting for patients with an atherosclerotic ascending aorta.

OBJECTIVES: We review the outcome of coronary artery bypass grafting in patients with a severe atherosclerotic ascending aorta. METHODS: Subjects were 31 patients averaging 69.4 +/- 6.9 years old studied from 1990 through 1998. Ascending aortic lesions were assessed using epiaortic echo and 2 types of aortic nonclamping techniques applied. In 29 patients operated on in the early years, bypass grafting was conducted on the hypothermic fibrillated heart in 22 and on the beating heart in 7. The remaining 2 underwent off-pump coronary artery bypass grafting more recently. For cases with multivessel disease, we used composite grafting. RESULTS: Three patients developed mild stroke and 5 died within 30 days of surgery--4 from multiple emboli (1 accompanied by a stroke) and 1 from perioperative myocardial infarction. One hospital death occurred due to brain damage and multiorgan failure following unexpected rupture of a saphenous vein graft. No cardiac deaths occurred in the late stage of our series. Actuarial survival was 73.0% for 3 years and 68.0% for 5 years. Freedom from cardiac events was favorable in the remaining 25 survivors. CONCLUSIONS: Outcome was suboptimal for the risks involved. Recent technical advances, including coronary surgery on the beating heart with or without cardiopulmonary bypass using variable in-situ or free arterial grafts, associated with adequate evaluation of systemic atherosclerosis, should improve this outcome.

Aged↗
PubMed2001

Early and late results of partial plication annuloplasty for congenital mitral insufficiency.

BACKGROUND: Partial plication annuloplasty is the main technique for congenital mitral insufficiency because this technique allows the mitral anulus to grow, in contrast to ring annuloplasty. However, this technique is not satisfactory for mitral insufficiency with some anomalies of the mitral valve apparatus. METHODS: Forty-one patients underwent partial plication annuloplasty for mitral regurgitation from July 1979 to December 1998. Mitral regurgitation associated with an atrioventricular defect, an atrioventricular discordance, and a univentricular heart was excluded from this study. RESULTS: There were no early or late deaths. In early results, partial plication annuloplasty was more effective for mitral regurgitation with abnormality of the posterior leaflet (n = 14) or normal leaflet motion (n = 8) than with abnormality of the anterior leaflet and its apparatus (n = 14) or absence of chordae (n = 4). The mean follow-up period was 145.8 months. During the follow-up period, 2 patients underwent mitral valve replacement, and a third patient underwent mitral valve repair with partial plication annuloplasty after the first repair. The main cause of mitral regurgitation of 2 of the 3 patients was absence of chordae. The actuarial freedom from reoperation rate was 94.9% +/- 3.6%, 91.9% +/- 4.7%, and 91.9% +/- 4.7% at 5, 10, and 15 years after the operation, respectively. CONCLUSION: Early and long-term results of partial plication annuloplasty were acceptable for congenital mitral insufficiency with any type of malformation of the mitral valve, and results were excellent with abnormality of the posterior leaflet and its apparatus or normal leaflet motion. However, late results were suboptimal for mitral regurgitation with absence of chordae. Other techniques, such as artificial chorda replacement, should be adapted in these cases.

Actuarial Analysis↗
PubMed2001

Telomerase activation and p53 mutations in urethane-induced A/J mouse lung tumor development.

The mouse telomerase holoenzyme, which synthesizes telomeric DNA de novo, is a ribonucleoprotein complex that includes the mouse telomerase RNA component (mTERC), mouse telomerase-associated protein (mTEP1) and mouse telomerase reverse transcriptase (mTERT). To determine the role of telomerase in urethane-induced lung tumorigenesis in A/J mice we examined telomerase activity and the expression of each telomerase subunit in 20 tumor samples, harvested at 16, 28, 40 and 50 weeks after urethane treatment. The telomeric repeat amplification protocol assay showed that statistically significant telomerase activation occurred both early and late in tumorigenesis. Semi-quantitative reverse transcription-polymerase chain reaction analysis revealed that mRNA expression levels of mTEP1 and mTERT were up-regulated during tumor progression, while mTERC expression was not significantly different between tumors and normal lung. We further examined mTEP1 protein expression in normal lung tissue and lung tumors; western blot analysis showed preferential expression of mTEP1 protein in lung tumors compared with normal lung and immunohistochemistry revealed that a majority of the adenoma cells were positively stained in the nucleus, whereas only a few of the adjacent normal alveolar cells were immunoreactive. In addition, we investigated DNAs of the 20 tumor samples by single strand conformation polymorphism and sequencing analyses to examine whether alterations of the p53 gene in exons 5-8 were associated with telomerase activity. Although we found one nonsense, two missense, two silent and one simultaneous double mutation at different codons in six late stage tumors, there was no apparent correlation between telomerase activity and p53 mutations. Collectively, these results suggest that mTEP1 as well as mTERT may be involved in the regulation of telomerase activity and that telomerase activation may contribute to lung tumorigenesis in A/J mice independently of p53 gene alterations.

Animals↗
PubMed2001

Clinical characteristics of patients with constrictive pericarditis after coronary bypass surgery.

Constrictive pericarditis (CP) is an unusual sequela of cardiac surgery, so the present study evaluated the clinical characteristics of patients with CP after coronary artery bypass grafting (CABG). Four hundred and sixty-three patients who underwent isolated CABG between January 1989 and March 1999 were examined retrospectively. The first choice of treatment for postoperative pericardial effusion was non-steroid anti-inflammatory agents, and an increased dose of diuretics. The second treatment choice was corticosteroids or pericardial drainage. When CP was suspected during the follow-up period (mean, 54+/-31 months), cardiac catheterization was carried out to establish the diagnosis. Of the 463 patients undergoing CABG, there were 11 (2.4%) who developed CP after surgery. The median time to the onset of symptoms after CABG was 4 weeks (range, 3-96 weeks). On univariate and multivariate analysis, normal left ventricular ejection fraction, warfarin administration, and early postoperative pericardial effusion were significantly associated with a greater potential of postoperative CP. The effusion was bloody in all cases of pericardial drainage despite warfarin therapy. Not draining the postoperative effusive pericardial effusion was a risk factor for the development of CP. Pericardial drainage for patients with significant effusion after CABG is important for the prevention of subsequent CP, especially in those patients being treated with warfarin or with normal left ventricular function.

Aged↗
PubMed2001

Aortic laceration due to prolapse of the bicuspid aortic valve: case report.

Reports of aortic regurgitation due to rupture of the aortic valve commissures are rare. Prompt surgical intervention is necessary, as the condition results in rapid, progressive heart failure and subsequent death. We report the case of a 78-year-old man who presented with aortic laceration and cardiac tamponade that was probably induced by prolapse of the bicuspid aortic valve. We speculate that prompt initial surgery may have prevented aortic laceration and cardiac tamponade in this patient. Thus, in order to optimize clinical outcome, clinicians must consider early, precautionary surgical management in patients who have sudden cardiac failure due to aortic regurgitation associated with prolapse of the bicuspid aortic valve.

Aged↗
PubMed2001

De Vega annuloplasty and Carpentier-Edwards ring annuloplasty for secondary tricuspid regurgitation.

BACKGROUND AND AIM OF THE STUDY: Residual or recurrent tricuspid regurgitation (TR) has been reported after several types of surgical repair. The development of late TR is an important complication of left heart surgery. The results of De Vega annuloplasty were compared with those obtained after Carpentier-Edwards ring (CE ring) annuloplasty in patients with secondary TR. METHODS: The records of 45 patients who underwent surgery for secondary TR between January 1995 and July 2000 were reviewed retrospectively. Twenty-eight patients underwent De Vega annuloplasty, and 17 had a CE ring annuloplasty. The groups were similar with respect to associated cardiac lesions. No significant preoperative differences were observed in NYHA functional class, TR grade, and pulmonary artery pressure between the two groups. RESULTS: One CE patient died of left ventricular dysfunction after postoperative bleeding. The 28 De Vega patients and remaining 16 CE patients had an uneventful recovery, and were discharged. Tricuspid ring size after repair was similar between groups. Mean (+/- SD) follow up in the entire patient cohort was 39+/-23 months (range: 6 to 75 months). TR recurrence was rated as grade II or III in 13 patients (45%) after De Vega annuloplasty, but was grade II or III in only one patient (6%) patient after CE ring annuloplasty. There was a significant difference in TR recurrence between the groups (p = 0.027), but no significant difference in NYHA class. CONCLUSION: CE ring annuloplasty significantly decreased the recurrence of TR; thus, CE ring annuloplasty is superior to De Vega annuloplasty in patients with secondary TR.

Aged↗
PubMed2001

[Emergent surgical treatment of type A acute aortic dissection in an elderly patient].

An 86-year-old man with severe chest pain and shock was transferred to our hospital. Computed tomography revealed type A aortic dissection with cardiac tamponade. He needed intubation and closed chest massage preoperatively. At operation, intrapericardial space was filled with clotted blood and rupture of the ascending aorta was confirmed. He underwent a successful emergency graft replacement of the ascending aorta. Postoperative course was uneventful except for mild hemianopsia due to cerebral infarction. He had recovered to be able to walk and is doing well.

Acute Disease↗
PubMed2000

[Long-term effect of polystan monocusp ventricular outflow patch after right ventricular outflow tract reconstruction].

Forty-eight patients who underwent right ventricular outflow tract reconstruction with Monocusp Ventricular Outflow Patch (MVOP) fifty-five times and survived surgery, were reviewed in this study. Mean age at surgery was 6.4 years-old and mean follow-up interval was 75.2 months. There was no late death, however reoperation was performed 7 times. Freedom from reoperation rate was 97.2% and 80.7% after 5 and 10 years after surgery, respectively. The main cause for reoperation were right ventricular outflow obstruction RVOTO (5 cases). All of the RVOTO occurred at the distal end of the anastomosis. However, there was no RVOTO in patients who underwent RVOTR with MVOP during the past ten years. So, we considered the cause of RVOTO a technical problem. Pulmonary regurgitation was one to two degree early after surgery, and had worsened by almost two or three degrees more than 5 years after surgery. Moreover, five of six patients who underwent cardiac catheterization more than 10 years after surgery had three degrees of pulmonary regurgitation as well as a large CTR. In conclusion, according to long-term results, especially more than 10 years post operatively, pulmonary regurgitation was the most important problem.

Adolescent↗
PubMed2000

[A surgical case of acute massive pulmonary embolism associated with a giant free-floating inferior vena cava thrombus].

The risk and mortality of pulmonary embolism is high in patients with free-floating inferior vena cava thrombi. We present a successful surgical case of a 70-year-old male who had acute massive pulmonary embolism associated with a giant free-floating inferior vena cava thrombus extending above the renal veins. Emergent thrombectomy of the pulmonary artery and the inferior vena cava using cardiopulmonary bypass was carried out because he was considered at high risk for fatal recurrent pulmonary embolism. Prophylactical insertion of a Greenfield filter in the inferior vena cava was added. In this report, diagnosis and treatment of inferior vena cava thrombosis is also discussed.

Acute Disease↗
PubMed1999

Reactive oxygen species play an important role in the activation of heat shock factor 1 in ischemic-reperfused heart.

BACKGROUND: The myocardial protective role of heat shock protein (HSP) has been demonstrated. Recently, we reported that ischemia/reperfusion induced a significant activation of heat shock factor (HSF) 1 and an accumulation of mRNA for HSP70 and HSP90. We examined the role of reactive oxygen species (ROSs) in the induction of stress response in the ischemic-reperfused heart. METHODS AND RESULTS: Rat hearts were isolated and perfused with Krebs-Henseleit buffer by the Langendorff method. Whole-cell extracts were prepared for gel mobility shift assay using oligonucleotides containing the heat shock element. Induction of mRNA for HSP70 and HSP90 was examined by Northern blot analysis. Repetitive ischemia/reperfusion, which causes recurrent bursts of free radical generation, resulted in burst activation of HSF1, and this burst activation was significantly reduced with either allopurinol 1 mmol/L (an inhibitor of xanthine oxidase) or catalase 2x10(5) U/L (a scavenger of H2O2). Significant activation of HSF1 was observed on perfusion with buffer containing H2O2 150 micromol/L or xanthine 1 mmol/L plus xanthine oxidase 5 U/L. The accumulation of mRNA for HSP70 or HSP90 after repetitive ischemia/reperfusion was reduced with either allopurinol or catalase. CONCLUSIONS: Our findings demonstrate that ROSs play an important role in the activation of HSF1 and the accumulation of mRNA for HSP70 and HSP90 in the ischemic-reperfused heart.

Allopurinol↗
PubMed1999

Combined cardiac surgery and total thyroidectomy: a case report.

A 65-year-old woman with aortic stenosis, ischemic heart disease, and Graves' disease had complained of effort angina. She then suffered from liver dysfunction due to treatment with antithyroid drugs. One year after the start of radioiodine administration, she demonstrated unstable angina with palpitation and sweating. Laboratory studies revealed a recurrent hyperthyroid state, and a second coronary angiogram revealed progressive ischemic heart disease. Combined coronary artery bypass grafting, aortic valve replacement, and total thyroidectomy were performed. The postoperative course was uneventful without any problems associated with hyperthyroidism or hypothyroidism. Combined cardiac surgery and total thyroidectomy can be performed safely if the perioperative levels of thyroid hormone are maintained at euthyroid or hypothyroid levels.

Aged↗
PubMed1996

Reperfusion causes significant activation of heat shock transcription factor 1 in ischemic rat heart.

BACKGROUND: The myocardial protective role of heat shock protein (HSP) has been demonstrated, and there has been increasing interest in stress response in the heart. We examined the DNA-binding activity of heat shock transcription factor (HSF), by which the transcription of heat shock genes is mainly regulated, during heat shock or ischemia/reperfusion in isolated rat heart. METHODS AND RESULTS: Rat hearts were isolated and perfused with Krebs-Henseleit buffer by the Langendorff method. Whole-cell extracts were prepared for gel mobility shift assay using oligonucleotides containing the heat shock element, which is present upstream of all heat shock genes. Induction of mRNAs for HSP70, HSP90, and GRP78 (glucose-regulated protein) was examined by Northern blot analysis. Although the activation of HSF during global ischemia was weak and rapidly attenuated, postischemic reperfusion induced a significant activation of HSF. In addition, although HSP70 mRNA was hardly induced during ischemia, its burst induction was detected during postischemic reperfusion. Supershift assays using specific antisera for HSF1 and HSF2 revealed that ischemia/reperfusion as well as heat shock induced the activation of HSF1 in hearts. Although the expression of HSP70 mRNA during heat shock was more vigorous than the expression during ischemia/reperfusion, the induction of HSP90 mRNA in postischemic reperfusion was significantly greater than that in heat shock. CONCLUSIONS: Our findings demonstrated that reperfusion causes a significant activation of HSF1 in ischemia-reperfused heart. The striking contrast between the induction of HSP70 mRNA and that of HSP90 mRNA suggests the presence of regulatory mechanisms other than HSF.

Animals↗
PubMed1995

[Surgical treatment of congenital aortic stenosis by aortoseptal approach].

Between 1975 and 1994, six patients under 15 years old with congenital aortic stenosis underwent relief of left ventricular outflow tract obstruction (LVOTO) by aortoseptal approach. Although we got satisfactory relief of LVOTO in all patients, there were two late deaths. In one patient with residual ventricular septal defect (VSD), intractable ventricular arrhythmia developed 12 years postoperatively. Although the residual VSD closure was performed, the patient died of the arrhythmia. The another one who was the youngest 4-year-old boy suddenly died 4 months postoperatively. The detail about his death was unknown, but we presumed ischemic heart attack as the cause of his death. In 3 of remaining survived 4 patients, we encountered a few complications. They were right ventricular outflow obstruction, coronary artery injury and conduction system injury. All complications and problems we encountered in this series were related to the incision and the reconstruction of aortoseptal approach. In conclusion, the aortoseptal approach is effective technique for relief of LVOTO, but on the other hand it is invasive and not so safe operation. So we should be cautious about these complications and problems.

Adolescent↗
PubMed1994

[Right ventricular function after aorto-coronary bypass surgery: with relation to the site of right coronary artery occlusion].

Postoperative right ventricular function was evaluated serially by thermodilution techniques (REF-1, Edwards Laboratories) in patients who underwent aorto-coronary bypass surgery with uneventful postoperative recovery. The patients were divided into three groups depending on the location of critical stenosis of the right coronary artery. The stenosis was proximal to the right ventricular branch in group I (n = 13), distal to the right ventricular branch but proximal to the acute marginal branch in group II (n = 13) and distal to the acute marginal branch in group III (n = 11). Control (n = 20) consisted of the patients with no significant stenosis of the right coronary artery. Cardiac index, intracardiac pressures and amount of cathecolamin used during postoperative course showed no significant differences among the groups including control. With the use of cathecolamine after surgery, right ventricular ejection fraction (RVEF) rose and right ventricular volumes (RVEDV and RVESV) decreased in all the groups except for group I. These values in group I were unchanged. Thus, there were significant differences in RVEF, RVEDV and RVESV between group I and control. These results mean that right ventricular dysfunction may remain even long after occlusion of the proximal right coronary artery.

Aged↗