Biomedical subjects

S Ohtake

Publications and source records attributed to S Ohtake.

At least 37 records · Page 2Linked to original sources

PubMed2001

Clinical application of vacuum-assisted cardiopulmonary bypass with a pressure relief valve.

OBJECTIVES: Hemodilution induced by cardiopulmonary bypass (CPB) often prevents open heart operations without blood transfusion because of a large CPB-priming volume. A vacuum-assisted venous drainage system appears to overcome this problem and our previous experimental study demonstrated the beneficial effect of a vacuum-assisted CPB with a pressure relief valve. In this study, we clinically applied this novel system, and evaluated its efficacy by comparing it with the results of a conventional siphon-dependent drainage system. METHODS: Sixty patients undergoing open heart operation were divided into Group V (vacuum-assisted system, n=30) and Group S (siphon-dependent system, n=30). The vacuum-assisted system contains a powerful vacuum generator and a pressure relief valve to keep the negative pressure in the reservoir constant when the blood suction is used. RESULTS: The CPB-priming volume was significantly smaller in Group V (V vs. S: 1071+/-88 vs. 1405+/-137 ml; P<0.01), resulting in the lower hemodilution in Group V evidenced by the minimum hemoglobin level (V vs. S: 6.83+/-1.06 vs. 5.78+/-0.79 mg/dl; P<0.01) and blood transfusion rate (V vs. S: 9 vs. 20%; P<0.01). There were no significant differences in the plasma free hemoglobin level and the reduction ratio of plasma haptoglobin between the groups. CONCLUSIONS: These data demonstrate that this vacuum-assisted CPB can provide simplification of the CPB circuit, resulting in a smaller CPB-priming volume and lower hemodilution. This vacuum-assisted CPB may attenuate the negative effect of CPB by minimizing hemodilution and appears to be a useful modification to accomplish no blood-requiring open heart operations.

Blood Transfusion↗

PubMed2001

Analysis of sympathetic nerve activity in end-stage cardiomyopathy patients receiving left ventricular support.

BACKGROUND: The left ventricular assist system (LVAS) has been used increasingly for patients with end-stage heart failure who are awaiting transplantation. Sympathetic nerve activity is known to correlate with cardiac function in chronic heart failure patients, but little is known about sympathetic nerve activity during LVAS support. In this study, we examined the status of sympathetic nerve activity in relation to mechanical support. METHODS: In this study, we included 10 consecutive patients with end-stage cardiomyopathy who were on LVAS support for at least 2 months (duration, 222 +/- 59 days). None of these patients achieved enough functional recovery to be taken off LVAS. In these patients, we used iodine-125-metaiodobenzylguanidine (125I-MIBG) scintigraphy to examine the change of sympathetic nerve activity after LVAS implantation, and compared the results with the change of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) levels as well as with histologic optional findings. Samples for ANP and BNP measurement were obtained before and 30 days after LVAS implantation. Specimens for histologic analysis were obtained at the time of LVAS implantation and at the time of cardiac transplantation or autopsy. RESULTS: We observed marked decrease in serum levels of ANP and BNP 1 month after LVAS implantation. But myocardial sympathetic nerve function, which was evaluated with 125I-MIBG scintigraphy and expressed as the heart-to-mediastinum activity ratio, remained below normal even 2 months after the LVAS implantation (1.57 +/- 0.19; normal, 2.34 +/- 0.36). Serial histologic analysis in these 10 patients showed continuous increase in percentage of fibrosis and cell diameter despite ventricular unloading by the LVAS. CONCLUSIONS: Sympathetic nerve function, which was evaluated on 125I-MIBG scintigraphy, did not improve during left ventricular support. Because none of the patients included in our study showed improvement in cardiac function or histologic findings, the recovery of myocardial sympathetic nerve function may be an important factor in myocardial recovery for cardiomyopathy patients on LVAS support.

3-Iodobenzylguanidine↗

PubMed2001

Controlled nicorandil administration for myocardial protection during coronary artery bypass grafting under cardiopulmonary bypass.

Nicorandil is a hybrid potassium channel opener, and recent experimental studies have demonstrated its efficacy in myocardial protection against ischemia-reperfusion. This clinical study was designed to examine the myocardial protective effect of nicorandil administered during cardiopulmonary bypass. Seventy adult patients, 53 men and 17 women, undergoing elective coronary artery bypass grafting were randomly assigned to two groups, one receiving nicorandil during cardiopulmonary bypass (group N, n = 35) and the other receiving no nicorandil for control (group C, n = 35). Nicorandil was administered at each dose of 0.1 mg/kg into the cardiopulmonary bypass circuit according to the following schedule: (1) bolus injection at the initiation of cardiopulmonary bypass, (2) continuous infusion for 5 min before aortic cross-clamping, (3) bolus administration at 5 min before reperfusion, and (4) continuous infusion for 5 min before reperfusion. The time required for achieving cardiac arrest after the initial cardioplegia was significantly reduced in group N in comparison with that in group C. After aortic unclamping, the number of patients showing a significant ST segment change on the electrocardiogram was significantly fewer in group N, whereas the number of patients showing spontaneous recovery of heart beat was significantly greater. As for the myocardial protective effect, group N showed lower plasma levels of malondialdehyde, human-heart fatty acid-binding protein, and peak creatine kinase-MB, and required lower doses of catecholamine. Our results suggest that nicorandil administration during cardiopulmonary bypass provides enhanced myocardial protective effects against ischemia-reperfusion in patients undergoing coronary artery bypass grafting.

Adult↗

PubMed2001

Common cell-surface antigens functioning in self-recognition reactions by both somatic cells and gametes in the solitary ascidian Halocynthia roretzi.

The "contact reaction" is an extremely rapid allogeneic cytotoxic reaction (ACR) mediated by hemocytes in the solitary ascidian Halocynthia roretzi. It has been proposed that regulation of the alloreactivity of hemocytes may be involved in preference for fertilization or self-sterility in this species. To identify the receptors and target ligands involved both in self-recognition by somatic cells and self-discrimination by gametes, we produced monoclonal antibodies (mAbs) that inhibit the ACR mediated by hemocytes and tested their effects on fertilization. Six different mAbs that inhibit the ACR were prepared and categorized into three groups. Although all three mAbs seemed to have the same ability to inhibit the ACR, almost constant and statistically significant inhibition (CRB1.1) and infrequent but significant inhibition (CRB2.1, and CRB3.1) of the ACR were observed in the same pairs of animals. Pretreatment of the unfertilized eggs with CRB1.1, CRB2.1, and CRB3.1, resulted in the constant and statistically significant inhibition, infrequent but significant inhibition, and no inhibition, respectively, of fertilization. Antigens recognized by CRB1.1 (CRB1.1 antigens) were detected on the cell surface of all types of hemocytes and on the vitelline coat and follicle cells of unfertilized eggs. CRB2.1 and CRB3.1 antigens were detected on the surface of certain types of hemocytes and follicle cells, but not on the vitelline coat. CRB mAbs were directed against different epitopes in the N-linked glycan on glycoproteins. These common carbohydrate antigens on somatic cells and gametes may function in some recognition processes in ACR and fertilization in H. roretzi.

Animals↗

PubMed2001

Atypical membranoproliferative glomerulonephritis in a cat.

Membranoproliferative glomerulonephritis was observed in a 2-year-old male Japanese domestic cat with clinical renal failure. In the glomeruli, moderate mesangial hypercellularity with an increased mesangial matrix and thickening of the capillary walls were prominent. In addition, frequent duplication of the capillary walls, splitting, and spike formation were observed in the glomerular basement membrane. Granular cat IgG and complement component deposition were detected globally along the glomerular capillary walls and in the mesangium. Transmission electron microscopy revealed dense deposits in the subendothelial and subepithelial regions and the mesangium. Mesangial interposition was also observed. These glomerular lesions are also found in humans with membranoproliferative glomerulonephritis type III, which has not been reported in animals.

Animals↗

PubMed2001

[Is routine application of off-pump coronary artery bypass grafting warranted?].

The limitation and indication of off-pump coronary artery bypass grafting (OPCAB) remain controversial. Since May 1999, we have applied OPCAB for all isolated coronary bypass cases routinely. Intraoperative conversion to CCAB occurred in 8 patients (10.8%). The main reasons for conversion were intramyocardial coronary arteries and arythmia-induced hemodynamic instability in the acute phase of myocardial infarction. We evaluated the results of OPCAB as compared to conventional coronary artery bypass (CCAB) as a historical control. The operative mortality was 1.6% in both groups. Postoperative complications including renal failure and requirements of circulatory support were significantly less in OPCAB. Postoperative max CPK-MB value, the amount of postoperative bleeding and the requirement of transfusion were also significantly less in OPCAB. Only neurological complication in OPCAB was temporary delirium in a high-aged patient, whereas three patients developed neurological complications including permanent stroke in CCAB. Right heart bypass was effectively utilized to maintain hemodynamics and expose the posterior vessels in patients with severely dilated and poorly functioning left ventricle (EF: 24-31%) and a patient with multiple severe stenosis in cerebral arteries. Coronary angiogram performed after the operation demonstrated 94% of graft patency. These results warrant the further application of OPCAB for multivessel surgical revascularization.

Adult↗

PubMed2001

Aortic valve replacement combined with endoventricular circulatory patch plasty (Dor operation) in a patient with aortic valve stenosis and severe ischemic cardiomyopathy.

A 58-year-old woman with ischemic cardiomyopathy and aortic valve stenosis, underwent aortic valve replacement and simultaneous endoventricular circulatory patch plasty (Dor operation). She underwent coronary artery bypass grafting for severe triple vessel disease 10 years ago. Recently she started to show severe congestive heart failure. Aortic valve stenosis with pressure gradient of 85-mmHg was also found. Coronary bypasses were all patent, but the left ventricle (LV) was severely dilated (LVDd/Ds=71/61 mm) and the ischemic cardiomyopathy was considered as the cause. She successfully underwent aortic valve replacement and endoventricular circulatory patch plasty. The initial postoperative course was complicated with intractable ventricular arrhythmia, but subsequent course was smooth and the patient was discharged with improved symptoms (NYHA Class II). Postoperative catheterization showed decreased left ventricular volume and improved contractility. This case implies the role of LV remodeling procedure in the ischemic cardiomyopathy combined with aortic valve lesion

Aortic Valve Stenosis↗

PubMed2001

[Intentional limited operation for minute peripheral adenocarcinoma of the lung].

The purpose of this report is to evaluate the limited operation for peripheral minute adenocarcinoma of the lung. Firstly, 44 cases (47 lesions) of surgically resected minute peripheral lung adenocarcinoma, 10 mm or less in diameter, were reviewed using Noguchi's classification, and the correlation between high resolution CT (HRCT) images and the clinicopathological features was examined retrospectively. All type A and B adenocarcinomas (n = 14) had no recurrence and all cases were the air containing type by HRCT. Lymph node metastasis and lymphatic/vascular involvement were detected with type C, D, E, F and 3 cases among them were died for recurrence. Based on those results, from April 2000, intentional limited operation was prospectively performed for 14 patients (16 lesions) with peripheral nodule showing ground-glass opacity on HRCT. The pathological findings were type A (n = 9), type B (n = 5), and atypical adenomatous hyperplasia was one case (If the findings were confirmed type C, D, E, F by permanent section diagnosis, VATS lobectomy will be performed). We recommend limited operation should be performed in only type A or B adenocarcinoma and permanent section diagnosis is necessary to determine whether or not.

Adenocarcinoma↗

PubMed2001

Three-dimensional flow velocity quantification of Freestyle aortic stentless bioprosthesis by magnetic resonance imaging: surgical consideration.

The characteristics in flow dynamics of stentless bioprosthetic valve implanted in aortic position has been reported using Doppler echocardiography and beneficial results have been demonstrated in patients. Because some disturbed flow characteristics were seen clinically with existence of pressure gradient, the nature of flow-velocity characteristics was evaluated in patients receiving Freestyle stentless aortic bioprosthesis using new three-dimensional MRI method. In 19 patients after AVR with Freestyle bioprosthesis, flow-velocity study was conducted using velocity-encoding phase-contrast magnetic resonance imaging (MRI). Three-dimensional flow profiles were reconstructed. The implantation techniques were subcoronary (SC) in 10, root inclusion (Incl) in 6, and full root (FR) in 3 patients. These results were compared to 4 pts with stented bioprosthesis and 4 healthy volunteers. In 3-D flow velocity profiles, there were variations from almost normal pattern to some disturbed flow pattern. All patients of FR showed the parabolic flow pattern nearly equal to normal subjects. Over half of the patients with SC and Incl showed disturbed flow pattern with increased pressure gradient. Although hemodynamically acceptable, Freestyle aortic bioprosthesis showed some degree of flow disturbance in subcoronary or inclusion method with increased transvalvular velocity that may cause late problems, and these findings evaluated by 3-D method should be implicated in surgical consideration.

Aged↗

PubMed2000

CD8-depleted donor leukocyte transfusions for cytomegalovirus antigenemia in patient with acute lymphoblastic leukemia treated with allogeneic CD34(+) cell transplantation.

A 24-year-old man with acute lymphoblastic leukemia received an allogeneic CD34(+) cell transplant from an HLA-mismatched sibling because of refractory disease. The CD34(+) cells were enriched by the immunomagnetic method. One month after the transplant his situation became complicated due to cytomegalovirus (CMV) antigenemia, which was resistant to treatment with ganciclovir. He was treated with CD8(+) cell-depleted donor lymphocyte transfusions (CD8-depleted DLT). After CD8-depleted DLT, the CMV antigenemia disappeared completely. This case report suggested that CD8-depleted DLT was an effective therapy for CMV antigenemia after allogeneic CD34(+) cell transplantation.

Adult↗

PubMed2000

Early experience of aortic valve replacement with the Freestyle stentless aortic bioprosthesis in elderly patients.

OBJECTIVES: Stentless bioprostheses have been gaining popularity in recent years as hemodynamically superior alternatives to conventional stented bioprostheses. METHODS: Between July 1996 and November 1998, 13 patients with aortic valve disease, 7 males and 6 females with a mean age (+/- SD) of 68 +/- 5 years, underwent an aortic valve replacement using the Medtronic Freestyle aortic bioprosthesis. The predominant lesions were stenosis in 8 patients and regurgitation in 5, while 2 patients had endocarditis. The operation was performed by a subcoronary technique in 9, root-inclusion technique in 3, and full root technique in 1 patient. RESULTS: Throughout the follow-up periods (with average follow-up period of 20.6 months), there was no hospital mortality, though there was one late death of unknown cause. The New York Heart Association class improved in all patients. The peak transvalvular gradient decreased from 18.4 +/- 9.8 to 12.6 +/- 9.6 mmHg, and the effective valve orifice area increased from 2.30 +/- 0.96 to 2.59 +/- 1.05 cm2 between the 1-month and the 6-month follow-up examinations. In patients with aortic regurgitation, the left ventricular end-diastolic/end-systolic volume index significantly decreased from 147 +/- 36/62 +/- 19 to 73 +/- 26/33 +/- 14 ml/m2 at 1 month after the operation. The left ventricular mass index also significantly decreased from 189 +/- 26 to 143 +/- 30 g/m2 in patients with aortic regurgitation and from 171 +/- 28 to 144 +/- 30 g/m2 in those with aortic stenosis. CONCLUSIONS: Although long-term follow-up is required for further evaluation, the early results appeared to indicate that the Freestyle aortic bioprosthesis was suitable for elderly patients requiring aortic valve replacement.

Aged↗

PubMed2000

Percutaneous cardiopulmonary support with heparin-coated circuits in postcardiotomy cardiogenic shock. Efficacy and comparison with left heart bypass.

OBJECTIVE: Percutaneous cardiopulmonary support, a simplified form of venoarterial bypass, using totally heparin-coated circuits, has recently come into clinical use. To clarify its efficacy in postcardiotomy cardiogenic shock to aid weaning from cardiopulmonary bypass, we compared results of percutaneous cardiopulmonary support with those of left heart bypass using a centrifugal pump. METHODS: We reviewed 18 patients treated between 1991 and 1998 who could not be weaned from cardiopulmonary bypass. Nine were aided by totally heparin-coated percutaneous cardiopulmonary support (PCPS group), and 9 supported by left heart bypass using a centrifugal pump (LHB group). In both groups, activated clotting time was controlled at 150-200 seconds using minimal doses of heparin as needed. RESULTS: Weaning and survival rates were higher in the PCPS group than in the LHB group (100% vs 55.6%, and 66.7% vs 22.2%). The PCPS group had a smaller amount of blood loss and needed a smaller amount of blood components in the immediate postoperative period. One percutaneous cardiopulmonary support patient required surgical re-exploration for postoperative bleeding (11.1%), but no clinical thromboembolic event occurred in the PCPS group. In the LHB group, 5 patients underwent surgical re-exploration for postoperative bleeding (55.6%), and 2 underwent thrombus extirpation in the left ventricle (22.2%). CONCLUSIONS: Although this study was retrospective and historical backgrounds could have been involved, our data suggest that totally heparin-coated percutaneous cardiopulmonary support system appears more effective as an aid to weaning from cardiopulmonary bypass and in short-term circulatory support for patients in postcardiotomy cardiogenic shock.

Adult↗

PubMed2000

Concomitant aortic root remodeling and coronary bypass in a patient with poor left ventricular function.

A 58-year-old man who had previously undergone rectal cancer surgery and who had poor left ventricular function underwent concomitant aortic root remodeling and coronary bypass for aortic root aneurysm with aortic regurgitation and severe coronary artery disease. Intermittent retrograde cold blood cardioplegia and leukocyte-depleted terminal blood cardioplegia were used for myocardial protection. Angiographic studies 1 month after surgery showed improved left ventricular function at an ejection fraction from 24 to 46%. During a 1-year follow-up, he has remained free of any cardiac event. Even though this report is limited to a case and follow-up, this technique is expected to be beneficial even in patients with severely depressed left ventricular function when the postoperative quality of life is considered.

Aortic Aneurysm↗

PubMed2000

Minimally invasive removal of infected pacemaker lead.

A 37-year-old woman with sick sinus syndrome suffered complications with recurring local infection at the generator pocket. Repeated debridement and antibiotic therapy was ineffective. Several attempts to remove leads via the implantation vein by direct traction were unsuccessful. We operated using cardiopulmonary bypass and applied a minimally invasive lower ministernotomy to obtain pleasing cosmetic results. After a right atriotomy, leads were removed. The minimally invasive approach gave satisfactory results, especially cosmetically.

Adult↗

PubMed2000

Coronary artery bypass graft in a renal transplant recipient.

A 47-year-old woman receiving predonine after renal transplantation underwent coronary artery bypass graft (CABG) surgery because of medically angina uncontrollable since 1996. Although she had an episode of acute renal rejection successfully treated with steroid pulse therapy, she had no angina or hemodialysis for over 2 years after CABG. We discuss postoperative management of renal recipient after cardiac surgery using lymphocyte-subpopulation monitoring.

Coronary Artery Bypass↗

PubMed2000

Importance of preoperative marking for minithoracotomy and for internal thoracic artery harvesting in minimally invasive direct coronary artery bypass grafting.

Minimally invasive direct coronary artery bypass has the potential to cause an anastomotic failure because of a limited exposure of the operative field and the difficulty of internal thoracic artery harvesting. In the present study, the importance of preoperative marking for an accurate minithoracotomy location and a successful internal thoracic artery harvest was assessed. A paperclip was placed on the left nipple and a chest X-ray was performed in the supine position. By aligning the position of the paperclip to the location of the left anterior descending coronary artery from a coronary arteriogram frontal view, the intercostal space for the minithoracotomy was thus determined. Marking the incisional intercostal space during preoperative left internal thoracic arteriography revealed the number and location of the internal thoracic artery branches at the beginning of the harvest. This preoperative marking technique allowed for a more adequate exposure of the operative field and an easier internal thoracic artery harvest which therefore contributed to an improvement in the operative results.

Aged↗

PubMed2000

Clinical evaluation of leukocyte-depleted blood cardioplegia for pediatric open heart operation.

BACKGROUND: Blood cardioplegia (BCP) is widely used for myocardial protection during open heart operation. However, BCP may have a chance to induce neutrophil-mediated myocardial injury during aortic cross-clamping. We clinically evaluated the myocardial protective effect of leukocyte-depleted blood cardioplegia (LDBCP) for initial and intermittent BCP administration in pediatric patients. METHODS: Fifty patients undergoing open heart operation for congenital heart disease between January 1997 and March 1999 were reviewed. Twenty-five were administered LDBCP for myocardial protection during ischemic periods (LDBCP group), and the remaining 25 were given BCP without leukocyte depletion (BCP group). RESULTS: The difference in plasma concentrations of malondialdehyde between coronary sinus effluent blood and arterial blood just after reperfusion in the LDBCP group (1.68 +/- 0.56 micromol/L) was significantly lower than that in the BCP group (2.35 +/- 0.62 micromol/L; p < 0.01). The LDBCP group showed significantly lower plasma concentrations of human heart fatty acid-binding protein at 50 minutes after reperfusion (LDBCP group, 103.5 +/- 38.7 IU/L; BCP group, 144.8 +/- 48.8 IU/L; p < 0.01) and the peak value of creatine kinase-MB during the first 24 postoperative hours (LDBCP group, 17.0 +/- 8.5 IU/L; BCP group, 26.0 +/- 11.6 IU/L; p < 0.01) than did the BCP group. The maximum dose of catecholamine was significantly smaller in the LDBCP group (LDBCP group, 3.20 +/- 2.18 microg x kg(-1) x min(-1); BCP group, 5.60 +/- 2.83 microg x kg(-1) x min(-1); p < 0.01). CONCLUSIONS: These results suggest the usefulness of LDBCP for protection from the myocardial injury that can be induced by BCP administration during aortic cross-clamping.

Blood Transfusion, Autologous↗

PubMed2000

The long-term outcome of a surgical repair of sinus of valsalva aneurysm.

BACKGROUND: In order to clarify the long-term outcome after surgical repair of a sinus of Valsalva aneurysm, we retrospectively assessed the operative results for patients treated in our institute. METHODS: The subjects were 27 patients who had undergone an operation between 1958 and 1996. For associated aortic regurgitation (AR) aortic valve repair was performed in 13 patients, 12 of whom had a ventricular septal defect (VSD); and an aortic valve replacement was performed in 3 patients, 1 of whom had a VSD. RESULTS: Five of the 13 patients who had aortic valve repair needed aortic valve replacement because AR developed after a period of between 7 and 13 years; those cases were complicated by VSD. Another 2 patients with mild AR also complicated by VSD are currently under observation. CONCLUSIONS: Although the postoperative outcome of the aortic valve repairs was good, cases that were complicated by VSD plus associated AR tended to develop AR later after surgery. Therefore, careful observation of the postoperative course is necessary.

Adolescent↗