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Biomedical subjects

M Hachida

Publications and source records attributed to M Hachida.

At least 55 records · Page 3Linked to original sources
PubMed1997

[Aortic valve replacement with the Toronto stentless porcine valve in a patient with clipping for cerebral arterial aneurysm].

A 48-year-old man, who had a cerebral arterial aneurysm, was admitted in our institution for operation of aortic valve stenosis. At first, he underwent clipping for cerebral arterial aneurysm under precise management of his hemodynamic condition. After the clipping operation, we performed aortic valve replacement with the Toronto stentless porcine valve because no anticoagulant therapy was ideal for patient with cerebrovascular disease and larger effective orifice area was preferable for stenotic aortic annulus. By means of echocardiography, mean pressure gradient of the aoric valve decreased from 42 mmHg to 22 mmHg after the valve operation. He was discharged from the hospital on the 23rd postoperative day, and he has been doing well without thromboembolic events and bleeding complications for five postoperative months. This experience suggest that the Toronto stentless porcine valve might be one of the valve of choice for patients with aortic valve disease and cerebrovascular disease.

Aortic Valve Stenosis↗
PubMed1997

[Implantation of the Novacor left ventricular assist device in a patient with dilated cardiomyopathy].

The Novacor left ventricular assist device has been widely applied as a bridge to heart transplantation. The patient, a 29-year-old, male had severe left ventricular failure due to dilated cardiomyopathy. The heart failure had progressively worsened and showed severely reduced wall motion of the left ventricle with fraction shortening of 0.03. His cardiac catheterization data with 7 r of dopamine infusion was as follows; RA(12), RV46/9EDP(12), PA(w)(31), cardiac Index 1.73 l/min/cm2. Novacor implantation was performed on March 11th, 1996. After the implantation the patient was extubated on day 3 and recovered rapidly. No complications, such as bleeding or thromboembolic episodes were seen. The patient was flown to the USA for cardiac transplantation on 24th, September, 1996. During the 11-hour flight from Narita to Los Angeles, he experienced no adverse effects. The patient underwent a successful cardiac transplant at UCLA Medical Center. His post-operative course was uneventful. We believe that either chronic circulatory support or the bridge to transplant using Novacor LVAS will be a significant breakthrough for the treatment of Japanese patients with severely deteriorated cardiomyopathy.

Adult↗
PubMed1997

Experience of patients with end-stage heart failure who underwent heart transplant at UCLA.

From 1993 to 1997, nine Japanese heart transplant candidates were accepted by the University of California at Los Angeles (UCLA) Medical Center, because no donor heart was available in Japan from a brain-dead patient. In all nine heart transplant patients described in this investigation, the preoperative diagnosis was dilated cardiomyopathy. One patient underwent implantation with a Novacor left ventricular assist device (Baxter Japan, Tokyo, Japan) as a bridge to heart transplant. All patients survived surgery and for a long-term period. The actuarial 1-year and 3-year survival curves of these patients were both 100%. The postoperative functional status was New York Heart Association Class 1 in all patients (100%). Immunosuppressive triple drug therapy (azathioprine, steroids, and cyclosporine) was given in seven patients; in two patients, cyclosporine was withdrawn and replaced by FK506 due to refractory rejection. The incidence of acute rejection per patient of more than grade 3 according to the International Society for Heart and Lung Transplantation was 6% within 3 months and 4.5% in 3-6 months; there was no rejection episode more than 6 months after transplantation. Post-transplant coronary artery disease was seen in two patients. However, no disease progression was seen after diltiazem therapy. These results may encourage heart transplantation in Japan.

Adult↗
PubMed1996

Combined aortic and mitral valve replacement in an adult with mucopolysaccharidosis (Maroteaux-Lamy syndrome).

A 41-year-old man with aortic stenosis, mitral stenosis, and tricuspid regurgitation due to Maroteaux-Lamy syndrome underwent aortic and mitral valve replacement with tricuspid annuloplasty. The annular diameter of the aortic and mitral valves was extremely small. The valve prostheses were 19 mm in diameter in the aortic position and 25 mm in the mitral position. Histologically, the valves showed thickening and hyalinization of the collagen fibers, and the presence of foamy cells that contained a large quantity of pure acid mucopolysaccharide. On an echocardiographic examination performed 2 years after the surgery, the peak systolic gradient of the trans-aortic valve was 18 mmHg at rest, and 26 mmHg during exercise. Careful observation of the residual pressure gradient will be needed. The patient's present New York Heart Association (NYHA) status is grade I and he has returned to work.

Adult↗
PubMed1996

Surgical treatment of ischaemic valve disease.

Mitral valve regurgitation secondary to ischaemic heart disease carries a significant mortality even after open-heart surgery. In this study, 21 patients with mitral regurgitation associated with ischaemic heart disease were evaluated with respect to valvular pathology. Pathological examination of the mitral valve revealed chorda elongation or rupture in seven patients (group 1), papillary muscle dysfunction in 10 (group 2), and papillary muscle rupture in four (group 3). Significant preoperative characteristics in each group were subacute haemodynamic deterioration in group 1, chronic severe left ventricular failure in group 2, and a high incidence of acute renal failure associated with haemodynamic shock in group 3. Mitral valve plasty was performed in six patients and mitral valve replacement, using the St Jude Medical valve, in 15. Fourteen patients underwent mitral valve surgery combined with coronary artery bypass grafting. Mitral plasty was applied to the patients with low left ventricular function with mean(s.d.) fraction shortening of 19.2(6.2)% compared with 30.2(8.4)% in patients with mitral valve replacement. There were no operative deaths. Of four late deaths, two in group 1 resulted from infection and myocardial infarction, respectively and one in group 2 resulted from arrhythmia. One patient in group 3 died from renal failure. It is suggested that incorporation of these therapeutic concepts may lead to satisfactory results in the surgical treatment of ischaemic mitral regurgitation.

Coronary Artery Bypass↗
PubMed1996

[Assessment of Japanese patients receiving heart transplants overseas].

No heart transplants have been performed in Japan due to various obstacles since the only operation performed in 1968. Since 1981, a number of patients requiring heart transplants have been accepted by foreign transplantation centers in England, the U.S.A., and Germany. This report describes an investigation of the postoperative course of these Japanese heart transplant patients and discusses the problems regarding transplantation in Japan. Of the 21 transplant patients, the diagnosis was dilated cardiomyopathy in 17, restrictive cardiomyopathy in 1, hypertrophic cardiomyopathy in 2, and congenital muscle dystrophy in 1. All patients survived surgery but three died in the long-term period. The causes of death were acute rejection (after 3 months), chronic rejection (after 50 months) and infection (after 30 months). The actuarial survival curve of these patients was 95.0% for one-year survival and 86.4% for three-year survival. The postoperative functional class was NYHA classification I in all patients (100%). Ninety-three percent of patients returned to work. Immunosuppressive therapies included triple drug therapy in 14 patients (66.7%), double drug therapy in 4 (19.0%), ciclosporin alone in 2 (9.5%) and FK506 in 2 (5.0%). The incidence of acute rejection was 1.56 episodes per patient per year within 3 months and 2.9 episodes per patient per year within 1 year. The postoperative courses of Japanese patients who underwent heart transplantation at foreign transplantation centers were satisfactory. These results will encourage heart transplantation in Japan.

Adolescent↗
PubMed1996

Effect of HTK solution for myocardial preservation.

The aim of this study was to investigate the efficacy of HTK solution for cardioplegia in the continuous 120-minute cross-clamping method in comparison with the conventional GIK method. In an experimental model, the efficacy of ketoglutarate and tryptophan in recovering cardiac function after 6 hours' preservation was evaluated. In Group A, in which ketoglutarate was excluded from the HTK solution, percent developed pressure was significantly decreased (p<0.01) and the released enzyme (CK-MB) was significantly increased, but coronary flow was not significantly changed. In Group B, in which tryptophan was excluded from the HTK solution, a significant decrease in percent developed pressure and coronary flow was seen (p<0.01). This indicated that ketoglutarate and tryptophan were effective in protecting the myocardium during the ischemia. In the clinical study, 54 open heart operations were performed with cardioplegic solution, using either HTK solution or GIK solution. In the HTK Group, the heart was exposed to 120 minutes' of ischemia after the infusion of HTK solution (3L). In the GIK group, intermittent GIK perfusion was performed every 30 minutes in association with continuous cold blood perfusion. Percent fraction shortening and cardiac index were not significantly different. However, CK-MB and HBDH were increased in the GIK group, postoperatively. Histological findings showed deterioration of the mitochondria and myocytes during ischemia in the GIK group. These data suggest that the effect of the cardioplegias in heart preservation was satisfactory in both groups, although the interval of intermittent perfusion was prolonged to 120 minutes in the HTK solution.

Animals↗
PubMed1996

[Hemodynamic plus series of St. Jude medical valve prosthesis in aortic position: early clinical outcome and reconsideration of its application].

St. Jude Medical Hemodynamic plus bileaflet valve prosthesis (HP) was employed in 7 cases undergoing aortic valve replacement since December 1993. Echocardiographic evaluation of left ventricular dimension and transvalvular pressure gradient was performed in 5 cases with 19 HP before and after operation. Each data was compared with those of 21 cases having undergone aortic valve replacement with 19 mm Standard model (19 SD). There was no significant postoperative change in left ventricular end-diastolic dimension (50 +/- 4 mm to 44 +/- 8 mm; p = NS) and left ventricular end-systolic dimension (34 +/- 4 mm to 34 +/- 9 mm; p = NS) in 19 HP cases. However, left ventricular end-diastolic dimension (51 +/- 11 mm to 41 +/- 8 mm; p < 0.05) and left ventricular end-systolic dimension (35 +/- 12 mm to 28 +/- 9 mm; p < 0.05) decreased in 19 SD cases. Transvalvular systolic peak pressure gradient was reduced significantly in both groups (19 HP: 94 +/- 38 mmHg to 43 +/- 19 mmHg; p < 0.05, 19 SD: 73 +/- 49 mmHg to 33 +/- 14 mmHg; p < 0.05). Poor reduction of left ventricular volume and high residual systolic pressure gradient in patients with 19 HP might be due to relatively high incidence of stenotic lesion in original aortic valve disease. In some cases with these critical aortic stenosis, radical annular enlargement procedure would provide more fundamental release of left ventricular outflow tract stenosis rather than one size increase of effective orifice area by employing HPs. Structural examination demonstrated that 19 HP had the same outer diameter of sewing flange with identical orifice ring as 21 SD (24 mm) did, and 17 HP had that of 19 SD (22 mm). Therefore, precise attention is needed for application of SJM-19 HP in patients with small aortic annuli.

Adolescent↗
PubMed1996

[Long-term results and special issues of operation for infective endocarditis].

Between 1977 and June 1996, 183 patients underwent operation for infective endocarditis (IE) at our institution. Long-term mortality and morbidity were analyzed according to the STS/AATS guidelines (1988). Operative mortality including hospital deaths was 4.9% in all patients. Actuarial survival (including all deaths) at 10 postoperative years was 79.6% after AVR (n = 91), 87.9% after MVR (n = 40) and 90.0% after DVR (n = 46). There was no significant difference among 3 groups. Reoperation free and freedom from all valve-related mortality and morbidity at 10 years were 94.0% and 70.4% after AVR, 90.9% and 83.7% after MVR and 93.4% and 79.7% after DVR, respectively. And the differences among 3 groups were not significant in both freedom proportions. Overall results in this series of patients were acceptable. However, several patients with active IE and extensive perivalvular abscess were not saved even if translocation method and/or other advanced surgical procedures were applied. Introduction of aortic valve homografts might be a key factor for successful treatment for patients with extensive IE lesion.

Adolescent↗
PubMed1996

Biventricular bypass with oxygenation for postcardiotomy ventricular failure.

Between January 1984 and March 1995, biventricular bypass (BVB) with oxygenation was used in 17 patients for postcardiotomy ventricular failure at the Heart Institute of Japan, Tokyo Women's Medical College. Of the 17 patients, 12 (70.6%) were weaned from the circulatory support, and 8 (47.1%) were discharged from the hospital. The time interval from the endo of cardiopulmonary bypass to the start of BVB was significantly shorter in weaned patients than in unweaned patients. The duration on support also has been shortened significantly in the last 6 years, compared with the earlier 6 years. Causes of death were severe heart failure or ventricular arrhythmia in 6 patients and multiple organ failure in 3 patients. These results suggest that early application and timely weaning from biventricular bypass with oxygenation might be the effective circulatory support of choice for treatment of postcardiotomy ventricular failure.

Adult↗
PubMed1996

[Cardiac surgery in patients on chronic hemodialysis].

From March 1993 to February 1993, 36 patients with chronic renal failure underwent cardiac surgery with intraoperative hemodialysis (HD). We examined and compared the medium term results of those patients cased upon the time periods of operation and types of heart disease. With respect to the time periods of operation, the 1st term (n = 12) was between March 1985 and February 1989, and the 2nd term (n = 24) was between March 1989 and February 1993. Concerning types of disease, Group A was comprised of 24 patients with ischemic heart disease, and Group B was comprised of 12 patients with valvular or congenital heart disease. Only one early death was observed in the 1st term (8.3%: LOS). As for late death, 5 cases were observed in the 1st term (45.3%), and 2 cases were observed in the 2nd term (8.3%). The actuarial survival rate (post 3 years) was 72.7% in the 1st term and 91.3% in the 2nd term. In each case, the survival rate of the 2nd term was significantly better than the that of the 1st term (p < 0.025). When compared cased upon the types of disease, the actuarial survival rate (post 6 years) was 84.6% in Group A, and 45.5% in Group B, respectively. This difference was statistically significant (p < 0.05). Causes of late death were cerebral hemorrhage in 5 cases, sudden and unknown in one and DIC in the remaining one patient. There were many postoperative complications in this series in addition to the above stated fatal ones. The majority of them, however, were successfully treated, if early diagnosis of them was obtained. During the perioperative period through the long-term period, incidents of fatal hemorrhage among patients on chronic dialysis were reduced by 1) strict management of hypertension; 2) HD without use of Heparin; and 3) with respect to patients who required Warfarin after valve replacement, through the careful anti-coagulant therapy which maintained the thrombo-test (TT) value at precise levels.

Adult↗
PubMed1996

Aortic valve replacement in small aortic annulus with or without annular enlargement.

BACKGROUND AND AIMS OF THE STUDY: Surgical treatments for aortic valve disease in the presence of a small aortic annulus need appropriate indications for operative procedures and precise selection of valve prostheses. The objective of this study was to compare long term results after aortic annular enlargement with those after operation using a small valve prosthesis. MATERIALS AND METHODS: Since 1980, 45 patients with small aortic annulus underwent operation at our institution. There were six men and 39 women, and their ages ranged from 16 to 69 with a mean of 45.6 years. Of these patients, 28 underwent aortic annular enlargements (Nicks' procedure in 13, Manouguian's in 12 and apico-aortic bypass in three patients) and 17 patients received standard aortic valve replacement with a small valve prosthesis (19 mm Standard St. Jude Medical). Mean follow up was 8.6 years in the enlargement group and 4.9 years in the standard group. RESULTS: Early mortality was 3.6% (1/28) in the enlargement group and 5.9% (1/17) in the standard group (NS). The 10-year actuarial survival including all deaths was 85.7% in the enlargement group and 62.7% in the standard group (p < 0.10). The rate of freedom from reoperation at 10 years was 90.7% in the enlargement group and 93.8% in the standard group (NS). The 10-year freedom from all valve-related events was 81.0% in the enlargement group and 58.8% in the standard group (p < 0.05). CONCLUSIONS: The above results suggest that long term mortality and morbidity after aortic annular enlargement might be superior to those after standard AVR with a small valve prosthesis.

Adolescent↗
PubMed1996

[Long-term results of cardiac valve replacement with a Delrin-disk model of the Björk-Shiley valve prosthesis--comparative analysis with the Spherical-disk model].

Records from 99 patients who received the Delrin-disk model (Group D) of the Björk-Shiley (BS) prosthesis between December, 1971 and November, 1974 were reviewed and compared to those from 248 patients who received the Spherical-disk model BS between January, 1975 and June, 1981 (Group S). Complete follow-up was obtained in 98.8% of the patients. The follow-up was over 1302.3 patient-years (mean 13.2 years per patient) in Group D and 2967.5 patient-years (mean 12.0 years per patient) in Group S. Early mortality was not significantly different (Group D: 18.2%, Group S: 10.5%). Of 15 late deaths in Group D, 12 (60%) were valve related and of 58 late deaths in Group S, 34 (58.6%) were valve related. The survival proportion based on Kaplan-Meier analysis, and which included early deaths, was equivalent in both groups (Group D: 65.7% at 21 years, Group S: 64.8% at 18 years). The freedom from reoperation was 74.3% at 21 years for Group D and 95% at 18 years for Group S (p < 0.005). The incidence of prosthetic valve dysfunction in Group D was significantly higher than that in Group S during 15 years after insertion of the valve. The freedoms from thromboembolism and valve-related events were not significant in both groups. Gross examination of the explanted Delrin disk found wear indentations and excessive clearance between the disk and the prosthetic ring. Therefore, disk wear was the primary cause of prosthetic valve dysfunction for the Delrin model. These results suggest that patients with the Delrin-disk model of the Björk-Shiley prosthesis should receive close follow-up for structural integrity of the valve. Further, reoperation might be needed due to significant valve dysfunction in this group of patients.

Adolescent↗
PubMed1995

Current strategy for severe heart failure with mechanical circulatory support.

In the last 10 years, 37 patients received assisted circulation or a ventricular assist device after open-heart operations at the Heart Institute of Japan. After cardiovascular surgery, 12 patients underwent venoarterial bypass (VAB), 13 had biventricular bypass (BVB), 8 had left ventricular bypass (LVB), and the remaining 4 received a left ventricular assist device (LVAD). Weaning and discharge rates of the patients by type of circulatory supports were 41.7 and 25.0% with VAB, 69.3 and 46.2% with BVB, 87.5 and 37.5% with LVB, 75.0 and 50.0% with LVAD, and 44.4 and 11.1% with PCPS, respectively. Concerning complications of postcardiotomy circulatory support, hemorrhage and ventricular arrhythmia postcardiotomy circulatory support, hemorrhage, and ventricular arrhythmia (immature weaning) decreased with low-heparinized isolated left ventricular supports (i.e., LVB, LVAD). However, profound biventricular failure, infection, and multiple organ failure remain as possible complications with any type of assisted circulation. These results suggest that early application of circulatory support and appropriate selection of the mode of support and devices used are important for successful circulatory support.

Adult↗
PubMed1995

Retrograde cerebral perfusion with hypothermic blood provides efficient protection of the brain: a neuropathological study.

Retrograde cerebral perfusion is a method that is recently being used for protection of the brain during operations on the aortic arch. This method is useful but is said to provide a limited time for protecting the brain. We designed an experiment in dogs to investigate neuropathologically the effect of protecting the brain for 120 minutes under: (1) circulatory arrest (CA); (2) retrograde cerebral perfusion with moderately cooled blood (RCPMC); and (3) retrograde cerebral perfusion with deeply cooled blood (RCPDC). We calculated the number of the abnormal cells of 400 hippocampal neurons per dog light microscopically. The number was 199 +/- 23 (mean +/- 1 SD) in the CA group, 149 +/- 50 in the RCPMC group, and 72 +/- 33 in the RCPDC group. The difference between the CA group and the RCPMC group was not statistically significant (p < 0.05), but there was a significant difference between the RCPMC and RCPDC groups (p < 0.05). The degree of cerebral protection provided by retrograde cerebral perfusion for 120 minutes is not sufficient when using moderately cooled blood. If we use deeply cooled blood at a temperature of about 10 degrees C, we should obtain a sufficient degree of protection of the brain.

Animals↗
PubMed1995

[Surgical results of aortic stenosis with or without left ventricular dysfunction--postoperative change of left ventricular function].

Between January 1980 and December 1992, 82 patients with aortic stenosis underwent isolated aortic valve replacement at our institution. Age of the patients ranged from 26 to 72 (58 +/- 6.4) years, and 58 were men and 24 were women. The patients were divided into two groups according to preoperative left ventricular ejection fraction (LVEF): 23 patients (LVEF < 50%, mean 39.7%; Group D) and 59 patients (LVEF > or = 50%, mean 62.6%; Group N). By means of echocardiography, LV function were evaluated before and at one month after operation in terms of left ventricular fractional shortening (LVFS), left ventricular systolic internal diameter (LVIDs), left ventricular mass index (LVMI), and left ventricular end systolic wall stress (ESWS). Postoperative early mortality including hospital death was 8.7% in group D (2 cases; myocardial infarction 1, cerebral complication 1) and 3.3% in group N (2 cases; myocardial infarction 1, low output syndrome 1), and this difference was not significant (NS) between two groups. The 5- and 12-year actuarial survival rate were 87.8% and 87.8% in group D, 91.5% and 87.6% in group N, respectively (NS). LVFS (pre/post) was 0.25 %/- 0/08/0.24 +/- 0.10 in group D, 0.38 +/- 0.10/0.32 +/- 0.10 in group N. The difference were significant before (p < 0.0005) and after (p < 0.005) operation between two groups. LVIDs (mm; pre/post) were 39.0 +/- 7.9/35.0 +/- 9.6 in group D, 28.7 +/- 7.3/229.3 +/- 7.6 in group N. The difference were significant before (p < 0.0005) and after (p < 0.01) operation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Examination of cardiac myxomas complicated with embolism].

Cardiac myxomas complicated with embolism were examined. Of 51 patients who underwent surgical excision of myxomas during the last 19 years, 10 patients (6 patients originated from left atrium, 4 patients originated from right atrium) had complications by embolisms. The embolism occurred in cerebral arteries (5 cases), a coronary artery (1 case), a retinal artery (1 case), and pulmonary arteries (4 cases). Patients were divided into an embolism group and a non-embolism group to investigate risk factors of embolism. Arrhythmia, diameter, narrow peducle, and tumor friability were thought to be major risk factors. Gelatinous and rough surface type tumor tended to cause embolism. Hypervascular tumors did not cause embolism. Among 10 patients, 2 patients had already had new embolism and another 2 patients had aggravated their symptoms before making diagnosis of myxoma. Myxomas should always be considered as a source of embolization, which need meticulous investigation and prompt indication of surgical resection.

Adolescent↗