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Hisataka Yasui

Publications and source records attributed to Hisataka Yasui.

43 records · Page 3Linked to original sources
PubMed2002

Adaptive immunity is severely impaired by open-heart surgery.

OBJECTIVE: The influence of open-heart surgery on antigen-specific immunity, also called adaptive immunity, remains to be clarified. We explored the effects of open-heart surgery on adaptive immunity. METHODS: In 8 consecutive adult patients undergoing elective cardiac surgery with cardiopulmonary bypass, we measured the T cell-response to purified protein derivative (PPD) antigen perioperatively. We separately measured the proliferation of T cells and the antigen presentation of antigen-presenting cells (APCs) using a cross-reaction system. RESULTS: T cell response to PPD antigen was severely impaired by open-heart surgery. Compared to preoperative values, T cell response to PPD antigen fell to 5.7 +/- 4.4% immediately after surgery, 4.5 +/- 3.2% on postoperative day (POD) 1, to 22.4 +/- 24.6% on POD 3 and to 50.1 +/- 34.3% on POD 7. T cell proliferation on POD1 decreased to 29 +/- 26%. APC antigen-presentation on POD 1 also decreased to 31 +/- 36%. CONCLUSIONS: Open-heart surgery impaired both T cell proliferation and the antigen-presentation. Such synergistic impairment severely impaired adaptive immunity. This impairment was both severer and longer than we anticipated based on previous studies using the response of T cells to lectin as a marker of cell-mediated immunity.

Aged↗
PubMed2002

Total cavopulmonary connection with an extracardiac conduit: experience with 100 patients.

BACKGROUND: In the Fontan procedures total cavopulmonary connection with an extracardiac conduit is a concern. The potential benefits of an extracardiac conduit may be the avoidance of postoperative supraventricular arrhythmias over the long-term, hemodynamic benefits due to laminar flow, possibility of completion without anoxic arrest, and applicability to anomalous systemic or pulmonary venous return, or both anomalous systemic and pulmonary venous return. We demonstrate early to midterm results of total cavopulmonary connection with an extracardiac conduit. METHODS: Between March 1994 and February 2000, a total of 100 patients underwent total cavopulmonary connection with an extracardiac conduit. In 27 patients, who underwent a single stage total cavopulmonary connection operation, 7 were done without palliation. Seventy-three patients had undergone a bidirectional Glenn shunt before completion of the total cavopulmonary connection. We used an expanded polytetrafluoroethylene tube graft as the extracardiac conduit. RESULTS: Cardiopulmonary bypass time was 133.2+/-55.2 minutes. Myocardial ischemic time was 38.5+/-23.2 minutes in 40 patients who needed cardioplegic cardiac arrest for intracardiac procedures. Intraoperative fenestration was done in only 1 patient. There were no operative deaths. During follow-up of 37.3 months, there were 5 late deaths. When compared with the patients treated by the lateral tunnel technique in our institute, there was no significant difference in actuarial survival rate, but the event free rate of the extracardiac conduit group was significantly superior to the lateral tunnel group. CONCLUSIONS: Total cavopulmonary connection with the extracardiac conduit produced good results in short to midterm follow-up.

Adolescent↗
PubMed2002

Extensive use of polytetrafluoroethylene artificial grafts for prolapse of bilateral mitral leaflets.

OBJECTIVES: There are an increasing number of reports concerning mitral valve repair by reconstruction of the chordae tendinae with the use of expanded polytetrafluoroethylene (PTFE) sutures. However, little information is available about the extended application or results of this technique for extended prolapse of bilateral mitral leaflets, which is considered to be difficult to repair. METHODS: Between October 1993 and May 1998, 17 patients (age range 16-74 years) who had from moderate to severe mitral regurgitation as the result of a prolapse of bilateral leaflets underwent mitral valve repair by reconstruction of artificial chordae with CV-4 expanded PTFE sutures. Either bilateral or unilateral Kay's suture annuloplasty was also performed to correct annular dilatation in all patients. RESULTS: No operative death or late mortality was observed. Before discharge, immediate postoperative echocardiography showed less than moderate mitral regurgitation in 16 of 17 patients. The follow-up was completed in all cases by a clinical examination and serial echocardiograms, and the median follow-up period was 52 months (range 27-82 months). There was one failure that required re-operation because of worsening mitral regurgitation (elongation of the anchored side of papillary muscle). When the re-operated patient was excluded from the following data, the degree of mitral regurgitation, estimated by echocardiography performed at recent follow-up, was none in four patients, trivial in eight patients, and mild in four patients. The systolic and diastolic dimensions of the left ventricle decreased significantly (P<0.01). CONCLUSIONS: Because replacement of artificial chordae was not complicated and seemed to preserve fine relationships among leaflet tissues, chordae, and papillary muscles, we therefore suggest that the extensive use of PTFE artificial chordae appears to be a promising procedure for the repair of all kinds of mitral lesions causing mitral regurgitation.

Adolescent↗
PubMed2002

Inelastic vascular prosthesis for proximal aorta increases pulsatile arterial load and causes left ventricular hypertrophy in dogs.

OBJECTIVES: Elastic property of the proximal aorta plays an important role in reducing pulsatile load to the ventricle. When a stiff vascular prosthesis is used for the proximal aorta, the pulsatile load increases. We designed this study to elucidate whether the increase in pulsatile load caused left ventricular hypertrophy. METHODS: We created an ascending aorta-abdominal aorta bypass in 9 dogs with a noncompliant vascular prosthesis. The aortic arch proximal to the left subclavian artery was occluded to direct blood flow into the bypass. Closed chest studies were performed after a median of 139 days (range 45-588) days. We assessed the pulsatile load of the ventricle by calculating characteristic impedance from pressure and flow velocity in the ascending aorta. The left ventricle was weighed, normalized with body weight, and compared with the control group, which had sham operations (7 dogs). RESULTS: Characteristic impedance of the bypassed dogs was 175% higher than the control (0.146 +/- 0.056 vs 0.053 +/- 0.014 mm Hg. s. mL(-1), P =.009), which resulted in wider pulse pressure (57 +/- 11 vs 25 +/- 11 mm Hg, P <.001). No difference was found in arterial resistance, cardiac output, or systolic blood pressure. Left ventricular weight normalized by body weight was significantly heavier in the bypass group (5.61 +/- 0.75 vs 4.15 +/- 0.62 g/kg, P =.001). CONCLUSION: Since there was no increase in arterial resistance, we conclude that the increase in pulsatile load was the cause of left ventricular hypertrophy. A stiff vascular prosthesis used for the proximal aorta may cause left ventricular hypertrophy.

Animals↗
PubMed2002

Off-pump CABG attenuates myocardial enzyme leakage but not postoperative brain natriuretic peptide secretion.

BACKGROUND: Off-pump coronary artery bypass surgery is considered to be less invasive compared with a conventional coronary artery bypass surgery, while objective assessment of its invasiveness has not been well established. The grade of invasiveness of off-pump CABG was evaluated by biochemical markers released from the myocardium. METHODS: Perioperative serial changes of myocardial enzyme leakage (creatine kinase-MB isoenzyme and troponin T) were evaluated in 217 patients who underwent coronary artery bypass surgery (28 off-pump CABG patients and 189 conventional CABG patients). Serial changes of atrial natriuretic peptide and brain natriuretic peptide secretion as markers of heart failure were also evaluated in 12 off-pump CABG patients and 49 conventional CABG patients. RESULTS: Myocardial enzyme leakage was significantly less in the off-pump CABG group, while increase of brain natriuretic peptides secretion were similar in both groups with its peak at the first postoperative day (246+/-46 pg/ml in the off-pump CABG group and 312+/-57 pg/dl in the conventional CABG group). CONCLUSIONS: Although off-pump CABG seems to be less invasive to the myocardial cells from the aspect of enzyme leakage, ischemic stress to the heart assessed by brain natriuretic peptide secretion was similar to that of conventional CABG. Careful monitoring and management throughout postoperative period is mandatory even in off-pump CABG procedure.

Aged↗
PubMedDate not supplied

GRAFT infection of thoracic aorta due to group C beta-hemolytic streptococcus--a case report.

A fatal case of late-onset graft infection of the thoracic aorta due to group C beta-hemolytic streptococcus is described. A 37-year-old male patient, who had a history of total aortic arch replacement for acute aortic dissection 8 years before, was admitted to the department. He suffered from toxic shock syndrome, disseminated intravascular coagulation (DIC), and acute renal failure. Group C beta-hemolytic streptococcus was detected from his blood; however, echocardiography, computed tomography (CT), and magnetic resonance imaging (MRI) failed to detect the focus of the infection. In spite of intensive care, including antibiotic therapy, artificial ventilation, and continuous hemodiafiltration, he died on the 18th day of hospitalization. Autopsy revealed that a small abscess was present at the proximal anastomotic segments of the patient's graft. A bite inflicted by his dog, 14 days before admission, was suspected to be the source of this bacterium. A rare case of graft infection of thoracic aorta in terms of causative organism, long period from graft replacement to graft infection, and site of infection is presented and discussed.

Abscess↗