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Hidekazu Hirai

Publications and source records attributed to Hidekazu Hirai.

13 recordsLinked to original sources
PubMed2006

Mycotic aneurysm of the distal aortic arch caused by Aspergillus.

We describe an unusual case of a thoracic aortic aneurysm caused by Aspergillus. A 70-year-old man underwent prednisolone and Ara-C treatments for a myelodysplastic syndrome. Blood examination revealed pancytopenia. Under these treatments, an aneurysm presented at the distal aortic arch. He underwent resection of the aneurysm with a graft repair covered by a pedicled omentum flap, followed by prolonged administration of micafungin and itraconazole for a mycotic aneurysm. The postoperative course was favorable without complications. Serum C-reactive protein became negative and he was discharged 2 months after the surgery. However, 4 months after the surgery, he died from worsening of the myelodysplastic syndrome. The prognosis for patients with mycotic aneurysms is poor due to their immunocompetent condition arising from underlying diseases. Therefore, in addition to prompt treatment with antifungal agents combined with surgical debridement, control of the underlying disease is essential for improving the outcome.

Aged↗
PubMed2006

Activation of mitogen-activated protein kinases, activator protein-1, and nuclear factor-kappaB during acute rejection after heterotopic heart transplantation in rats.

BACKGROUND: Activation of mitogen-activated protein kinases (MAPKs), including c-Jun NH2-terminal kinases (JNKs), extracellular signal-regulated kinases (ERKs), and p38MAPK during acute cardiac rejection is not clear. This study aimed to determine whether MAPKs and transcriptional factors such as activator protein-1 (AP-1) and nuclear factor-kappaB (NF-kappaB) were involved in acute rejection after cardiac transplantation. METHODS: Hearts from Lewis (LEW) rats (group C) or DA rats (group R) were transplanted into the abdomen of recipients (LEW). Grafts were collected at the 1st, 3rd, or 5th postoperative day (POD). ERKs were measured by Western blot analysis, and JNKs were measured by in-gel kinase assay. AP-1 and NF-kappaB DNA binding activities were determined using an electrophoretic mobility shift assay. We assessed functions of donor hearts using echocardiography. RESULTS: Heart rates and myocardial contraction significantly decreased at POD 5 in group R. Phosphorylated p42ERK and p44ERK in the left ventricular free wall (FW) and septal wall (SW) of group R significantly increased at POD 5 compared to those of group C at POD 1. Activities of p46JNK and p55JNK in the FW and SW of group R also significantly increased at POD 5. AP-1 DNA binding activities in the FW and SW of group R significantly increased at POD 5, and NF-kappaB DNA binding activities of group R significantly increased at PODs 3 and 5. CONCLUSIONS: We conclude that ERK, JNK, AP-1, and NF-kappaB are activated during acute rejection. The MAPK pathways may play an important role in acute cardiac rejection.

Animals↗
PubMed2005

Assembly and deployment of a branched arch stent graft using the transaortic approach.

Transaortic stent grafting is an alternative method for treating distal arch aneurysms. Total arch grafts are too bulky to be inserted into a sheath catheter during usual stent grafting methods. An assembling method that uses a chain stitch enables the deployment of any type of stent graft into the distal aorta without the need for a sheath catheter. We describe how to safely assemble and use a branched arch stent graft. We consider this method to be beneficial in selected cases involving extensive distal arch aneurysms or in patients with highly calcified aortas.

Aorta, Thoracic↗
PubMed2005

Relationship between granulocyte elastase and C3a under protamine dosing in on-pump cardiac surgery.

OBJECTIVE: The complement cascade and granulocytes are activated in on-pump cardiac surgery. If activation of complement directly regulates granulocytes, granulocyte elastase (GEL) should increase significantly after protamine administration. We examined the effect of protamine on granulocytes by protamine administration and observation of the effect on GEL and C3a. METHODS: Thirty patients who underwent coronary artery bypass grafting were randomly assigned to two groups. In 15 patients, protamine was administered 5 min after the termination of cardiopulmonary bypass, and was administered 35 min after cardiopulmonary bypass in the other 15 patients. All patients were perfused with heparin-coated circuits and received 300 IU/kg heparin and 3 mg/kg protamine. GEL and C3a concentrations were measured at 7 time points. RESULTS: GEL concentrations increased significantly just before aortic declamping and did not increase significantly after protamine administration. C3a concentrations, however, did not increase during cardiopulmonary bypass and did increase significantly after protamine administration. CONCLUSIONS: This study indicates that GEL does not increase after protamine administration and that complement concentration does not directly affect GEL release.

Aged↗
PubMed2004

A new poly-2-methoxyethylacrylate-coated cardiopulmonary bypass circuit possesses superior platelet preservation and inflammatory suppression efficacy.

BACKGROUND: Poly-2-methoxyethylacrylate (PMEA) is a new coating material, and several studies have revealed that PMEA-coated cardiopulmonary bypass (CPB) circuits have good biocompatibility. This study sought to compare this biocompatibility with those of heparin-coated and noncoated circuits. METHODS: Forty-five patients undergoing coronary artery bypass grafting were randomly assigned to PMEA-coated (group P, n = 15), heparin-coated (group H, n = 15), or noncoated (group N, n = 15) circuit groups. Clinical data and the following markers were analyzed: (1) platelet preservation by number of platelets; (2) complement (C) activation by C3a and C4a levels; (3) inflammatory response by interleukin-6 (IL-6) and interleukin-8 (IL-8) levels. RESULTS: Platelet numbers were significantly preserved in group P compared with groups N and H. Postoperative blood loss did not differ among the groups. During CPB, C3a values were significantly lower in group H (536 +/- 145 ng/mL) than in group P (1,458 +/- 433 ng/mL, p < 0.01) and group N (1,815 +/- 845 ng/mL, p < 0.01). The C4a values did not differ 60 minutes after CPB initiation among the groups. The IL-6 and IL-8 levels were significantly lower in group P and group H than in group N. CONCLUSIONS: The PMEA coating was superior to heparin coating and noncoating in preserving platelets, and was equivalent to heparin coating in terms of the perioperative clinical course and inhibition of inflammatory cytokines, but slightly inferior in reducing complement activation.

Acrylates↗
PubMed2004

Sonoclot analysis in cardiac surgery in dialysis-dependent patients.

BACKGROUND: Dialysis-dependent patients have multiple disorders of hemostasis; however, there are no reports of viscoelastic changes during cardiac surgery in such patients. METHODS: Hemostasis in dialysis-dependent patients during cardiac operations was evaluated. Thirty patients who underwent cardiopulmonary bypass (CPB) were studied: 6 with chronic renal failure undergoing dialysis (HD group), and 24 without hemodialysis. Blood samples were obtained at four points: before sternotomy, 30 and 90 minutes after the start of CPB, and after protamine administration. RESULTS: Activated clotting time (ACT) measured with Sonoclot analyzer was significantly correlated with ACT measured traditionally (r = 0.92; p < 0.001; y = 36.1 + 0.95x). Values for ACT measured with Sonoclot analyzer as well as traditional ACT increased significantly during CPB. Values for ACT measured with Sonoclot analyzer in the HD group were significantly longer than those in the control group. Before CPB, both ACT measured with Sonoclot analyzer and traditional ACT in the HD group were significantly longer than those in the control group; however, there were no significant differences in ACT measured with Sonoclot analyzer between the groups after CPB. Clot rates and peak signal values were significantly decreased during CPB in both groups, and returned to preoperative values after protamine administration. There were no significant differences in clot rate and peak signal values between the two groups. There were no differences between the two groups in changes of time to peak. Platelet counts in the HD group were significantly higher (p < 0.05) than those in the control group. There were no differences in platelet counts after CPB between the two groups. Antithrombin III levels decreased below 50% during and after CPB. Antithrombin III in the HD group was significantly lower (p < 0.01) than those in the control group. A significant time-group interaction was observed in antithrombin III levels. CONCLUSIONS: Sonoclot signatures in HD patients showed no significant differences in viscoelastic changes compared with non-HD patients.

Cardiopulmonary Bypass↗
PubMed2003

Rectus abdominis myocutaneous flap after unsuccessful delayed sternal closure.

Open chest management is one of the best options for severely impaired hearts after open-heart surgery. Reapproximation of sternal edges compresses the heart, so a less compressive method of chest wall reconstruction should be considered when sternal closure must be delayed. We applied a rectus abdominis myocutaneous flap approach in 3 patients after difficulties with delayed sternal closures. Two patients were weaned off intraaortic balloon pumping and survived without respiratory troubles or wound complications. This alternative method of chest reconstruction is useful in patients after an unsuccessful delayed sternal closure.

Aged↗
PubMed2003

Small-intestinal bleeding from angiodysplasia after aortic valve replacement.

An association between aortic stenosis and angiodysplasia of the gut has been reported, though this is unproven. In many instances, recurrent gastrointestinal bleeding originating from angiodysplasia has ceased following aortic valve replacement (AVR). A case is reported of massive bleeding from a small-intestinal angiodysplasia after AVR. The diagnosis was made using radioisotope-labeled red cell scintigraphy and selective angiography of the ileocolic artery soon after AVR. Selective embolization using sponge was performed, and bleeding ceased immediately. The time from onset of bleeding to completion of embolization was 6 h. However, signs of peritonitis appeared the next morning, and an emergency resection of the necrotic ileum was performed. Bleeding from angiodysplasia of the gut may occur after AVR, although the etiologic role of aortic stenosis in angiodysplasic hemorrhage is not clear.

Aged↗
PubMed2003

Effects of FK506 on acute allograft rejection in transplanted rat heart: the role of mitogen-activated protein kinases, AP-1 and NF-kappaB.

To scrutinize the effect of the immunosuppressant on acute allograft rejection as related to the intracellular signal transduction, heterotopic cardiac transplantation was performed from DA rat to Lewis rat with/without FK506. In the experimental group, recipients were given FK506 intramuscularly for 5 days. The control group received placebo. Allograft survivals were compared between two groups. For the assay of mitogen-activated protein kinase (MAPKs) families, activator protein-1 (AP-1) and nuclear factor-kappaB (NF-kappaB) in the left ventricular free wall (LV) and septum (SEP) of the grafts, rats were sacrificed on POD 5 (n=5 in each group). Extracellular signal-regulated kinase (ERK) and p38MAPK were measured using Western blot analysis. AP-1 and NF-kappaB DNA binding activities were measured by electrophoretic mobility shift assay. FK506 prolonged allograft survival (6.5 vs 31 days), and suppressed activation of myocardial MAPKs (ERK: 66% in LV and 67% in SEP, p38MAPK: 62% in LV and 72% in SEP), AP-1 (24% in LV and 18% in SEP), and NF-kappaB (41% in LV and 20% in SEP) (the mean value of activities in the control group was represented as 100%). These results suggest that the signal transduction pathways may play important roles in acute allograft rejection in rat cardiac transplantation.

Acute Disease↗
PubMed2002

Retropericardial hematoma complicating off-pump coronary artery bypass surgery.

We report the case of a retropericardial hematoma after triple-vessel off-pump coronary artery bypass grafting. Transesophageal echocardiography demonstrated a retropericardial hematoma that compressed the left atrium anteriorly and suppressed cardiac function. Injury to the pulmonary vein during placement of deep pericardial sutures and postoperative infusion of heparin were the likely causes of this rare but potentially fatal complication of an off-pump bypass operation.

Aged↗
PubMed2002

Infective endocarditis with myocardial abscesses complicating percutaneous transluminal coronary angioplasty.

A 73-year-old man who had undergone percutaneous transluminal coronary angioplasty developed infectious endocarditis caused by Staphylococcus aureus. Echocardiography revealed vegetations of the aortic valve and severe aortic regurgitation. Endotracheal intubation was required for progressive heart failure. Serum creatinine kinase was elevated (411 IU/l: normal 30 to 140 IU/l). Electrocardiography showed no ischemic changes. Aortic replacement was performed to treat progressive heart failure, but the patient could not be weaned off cardiopulmonary bypass and subsequently died. A post-mortem examination revealed multiple myocardial microabscesses and myocardial infarction due to embolic vegetation. The possibility of multiple abscess formation when severe ventricle dysfunction occurs in infectious endocarditis is emphasized.

Abscess↗
PubMedDate not supplied

Concomitant pulmonary embolectomy and excision of a left atrial myxoma.

We report a rare case of concomitant pulmonary embolectomy and excision of a left atrial myxoma. A 64-year-old obese woman developed a pulmonary embolism 13 days after an operation for a brain tumor. Echocardiography revealed a 3-cm left atrial mass attached to the atrial septum. Urgent surgery, including pulmonary embolectomy and excision of the left atrial mass, was performed. Histopathology confirmed that the mass was a left atrial myxoma. The postoperative course was uneventful.

Brain Neoplasms↗