Gen Shinohara

The Jikei University School of Medicine, Edo, Tōkyō, Japan

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Publications (27)20.07 Total impact

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    ABSTRACT: We experienced a case of a female infant with a double aortic arch (DAA) which formed an aortoesophageal fistula, leading to hemorrhagic shock. The patient had severe dyspnea at birth, and was intubated and tube-feeding was started through a nasogastric tube immediately after birth. A DAA was diagnosed by contrast-enhanced computed tomography. Due to abdominal organ malformation, we proceeded with abdominal surgery. Forty-nine days after birth, she suddenly developed massive hematemesis and went into hemorrhagic shock. The bleeding was stopped using an endoscope and was shown to have originated from the esophagus membrane. Compression of the esophageal wall by both the inserted nasogastric tube and vascular ring led to the development of ulceration, resulting in a fistula associated with massive hematemesis. An operation for a DAA was performed on the 53rd day after birth. The inferior side of the DAA was cut, to decompress the bronchus and esophagus and close the fistula. The patient's postoperative course was good and there was no further bleeding. In severe cases of a DAA who require respiratory intubation and tube feeding from a nasogastric tube it is important to carry out surgery as soon as possible.
    No preview · Article · Jan 2016 · Kyobu geka. The Japanese journal of thoracic surgery
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    ABSTRACT: Primary repair of the tetralogy of Fallot with absent pulmonary valve syndrome (TOF/APV) is associated with high mortality rates of 17-33%, especially in neonates. Our standard strategy involves a staged repair with a first palliation, performed during the neonatal period, that includes main pulmonary septation with an ePTFE patch, pulmonary arterioplasty for reduction of vascular dilation, and a modified Blalock-Taussig shunt. We performed successful repairs on two neonates with TOF/APV, one symptomatic and the other non-symptomatic, with this strategy. Case 1 : A 7-day-old boy had TOF/APV, with progressively worsening respiratory distress. His left bronchi, superior vena cava and left atrium were compressed by a dilated pulmonary artery, which was repaired by emergency surgery. Decreasing the diameter of the pulmonary artery (PA index from 2,550 to 525) relieved the compressed organs. Case 2 : A 16-day-old boy with TOF/APV with a main pulmonary artery that increased in diameter from 8 to 17 mm in the course of a single day. He was treated in the same fashion as Case 1. At 1 year of age, an intracardiac repair with tricuspid anuuloplasty was performed successfully. This strategy is much safer than a primary repair and is a good choice for neonatal repair of TOF/APV.
    Preview · Article · Jan 2015
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    Gen Shinohara · Koji Nomura · Kouichi Muramatsu
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    ABSTRACT: A 1-year-old girl with patent ductus arteriosus (PDA) was admitted for cardiac catheter examination which identified a 7.8 mm Krichenko D type PDA. An Amplatzer duct occluder (ADO) was used but fluoroscopy showed the device at an oblique angle and residual shunt. The girl underwent surgical removal of the device 2 days after deployment because of progression of residual PDA shunt and left pulmonary artery encroachment, suggesting device dislodgement. Median sternotomy was performed, cardiopulmonary bypass was established and dissection was carried out around the PDA. Marked protrusion of the PDA wall made by the ADO retention disc was noted. The main pulmonary artery was incised under cardioplegic arrest. The device was incarcerated in PDA and attempts to remove the device failed. Therefore delivery cable through sheath was reconnected to the device by its microscrew, and the pulmonary end of the device was recaptured into sheath. The incarceration was dissolved and the device was removed. PDA was ligated.
    Preview · Article · Jan 2015
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    ABSTRACT: An infectious aneurysm represents a potentially serious clinical condition because of its tendency to rupture and to be complicated with sepsis. Here we report an infantile case of infectious aneurysms of the brachiocephalic artery, occurring subsequent to mediastinitis. Chest computed tomography (CT) revealed aneurysms of the brachiocephalic artery after the recurrence of mediastinitis. The patient’s trachea was compressed by the brachiocephalic artery, which was displaced backward by the aneurysms. Urgent implantation of a hand-made covered stent, which was made of a metallic stent and a roll-shaped expanded polytetrafluoroethylene sheet, was performed. After deployment of the coveresd stent, the size of the aneurysms was diminished and compression of the trachea improved. After treatment with anti-methicillin-resistant Staphylococcus aureus (MRSA) medications, the mediastinitis has been in remission. The development of Horner’s syndrome was recognized as a complication of the stent deployment. Implantation of a covered stent represents an option for the treatment of infectious aneurysms.
    No preview · Article · Jan 2015
  • Kouichi Muramatsu · Gen Shinohara · Koji Nomura
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    ABSTRACT: Mid aortic syndrome is uncommon acquired or congenital condition characterized by segmental narrowing of the abdominal or distal descending thoracic aorta. If left untreated, it result in life threatening complications. We described the case of 2-year-old boy admitted to our hospital for hypertension and heart failure. Diagnosis of mid aortic syndrome was made with severe stenosis in distal descending aorta. With consideration of growth, we avoided bypass grafting and implantation with prothesic graft. For severe adhesion, we performed patch aortoplasty with 0.4 mm expanded polytetrafluoroethylene (ePTFE) patch. Postoperative course was unevetful. His blood pressure and left ventricular function was normalized. He was discharged on the 20st day after the surgery.
    No preview · Article · Aug 2014 · Kyobu geka. The Japanese journal of thoracic surgery

  • No preview · Article · Jan 2014

  • No preview · Article · Jan 2013
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    ABSTRACT: A patient with multiple leaks caused by active mitral prosthetic valve endocarditis with an annular abscess underwent repeat mitral valve replacement. To secure the new mitral prosthesis, sutures were placed through the healthy interatrial septal wall from right to left at the posteromedial region and then to the new prosthetic valve sewing cuff. In the anterolateral region, sutures were placed through the reconstructed annulus after debridement of the abscess and then reinforced with a pericardial xenograft patch. Postoperatively, the perivalvular leakage stopped and the patient recovered uneventfully.
    No preview · Article · Jun 2012 · General Thoracic and Cardiovascular Surgery
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    ABSTRACT: The benefit of terminal blood cardioplegia (TWBCP) is insufficient after prolonged ischemia associated with inevitable oxidant-mediated injury by this modality alone. We tested the effects of TWBCP supplemented with high-dose olprinone, which is a phosphodiesterase III inhibitor, a clinically available compound with the potential to reduce oxidant stress and calcium overload. We evaluated the effects with respect to avoiding oxidant-mediated myocardial reperfusion injury and prompt functional recovery after prolonged single-dose crystalloid cardioplegic arrest in a infantile piglet cardiopulmonary bypass (CPB) model. Fifteen piglets were subjected to 90 min of cardioplegic arrest on CPB, followed by 30 min of reperfusion. In group I, uncontrolled reperfusion was applied without receiving TWBCP; in group II, TWBCP was given; in group III, TWBCP was supplemented with olprinone (3 μg/ml). Myocardial performance was evaluated before and after CPB by a left ventricular (LV) function curve and pressure-volume loop analyses. Biochemical injury was determined by measurements of troponin-T and lipid peroxide (LPO) in coronary sinus blood. Group III showed significant LV performance recovery (group I, 26.5% ± 5.1%; group II, 42.9% ± 10.8%; group III, 81.9% ± 24.5%, P < 0.01 vs. groups I and II), associated with significant reduction of troponin-T and LPO at the reperfusion phase. No piglets in group III needed electrical cardioversion. We concluded that TWBCP with olprinone reduces myocardial reperfusion injury by reducing oxidant-mediated lipid peroxidation, and it accelerates prompt and persistent LV functional recovery with suppression of reperfusion arrhythmia.
    No preview · Article · Feb 2012 · General Thoracic and Cardiovascular Surgery
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    ABSTRACT: An in vivo study of piglets on cardiopulmonary bypass was performed to determine whether postconditioning has a cardioprotective effect after cardioplegic arrest in large animals. Eighteen piglets were subjected to 90 minutes of cardioplegic arrest followed by 30 minutes of reperfusion. In 6 animals (control), there was no intervention at reperfusion. In 6 other animals, 6 cycles of unclamping and reclamping for 10 seconds each were done before reperfusion (postconditioning 10), whereas 3 cycles of unclamping and reclamping for 30 seconds each were performed in another 6 piglets (postconditioning 30). Recovery of left ventricular contractility and diastolic function (percent of preischemic value) was significantly better in both postconditioning groups (contractility: 89.2% and 118.2; diastolic function: 142.3% and 120.4; in the postconditioning 10 and 30 groups, respectively) compared with the control (contractility: 46.1%; diastolic function: 218.5%). Recovery of global cardiac function (ventricular function curve analysis) was improved only in the postconditioning 30 group. Troponin-T release during reperfusion was significantly reduced in the postconditioning 10 group compared with all groups (plasma troponin-T was 0.58 ng/mL in postconditioning 10, 1.85 in postconditioning 30, and 2.54 in control). The myocardial lipid peroxide was significantly higher in the control group than in both postconditioning groups after reperfusion (199% vs 112% and 131%). Both postconditioning algorisms promoted functional recovery after cardioplegic arrest in a large animal model along with the limitation of lipid peroxidation with or without the reduction of troponin-T release.
    No preview · Article · Feb 2011 · The Journal of thoracic and cardiovascular surgery
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    ABSTRACT: First-stage palliation of hypoplastic left heart syndrome has been revolutionized by the recent introduction of a right ventricle-to-pulmonary artery (RV-PA) conduit as an alternative to a systemic-to-pulmonary shunt. However, most conduits are unvalved, and the use of valved xenografts was abandoned during the early era of this operation. We performed a successful modified Norwood operation in a 2-month-old infant with aortic atresia and ventricular and atrial septal defects using a hand-made down-sizing valved graft as an RV-PA conduit. The postoperative course was uneventful with well-balanced pulmonary and arterial perfusion. We believe that minimization of the regurgitant volume from an unvalved prosthetic conduit by utilizing this modification might be of benefit in this particular group of patients.
    No preview · Article · Jan 2011 · General Thoracic and Cardiovascular Surgery
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    ABSTRACT: A 5-month-old boy was presented for surgical repair of scimitar syndrome associated with right lung hyperplasia, severe pulmonary hypertension, ventricular septal defect (VSD), and atrial septal defect. The calculated shunt fraction (Qp/Qs) was 3.1:1.0, pulmonary vascular resistance was 4.6, and the perfusion lung scan showed a marked decrease (11%) in right pulmonary blood flow. Surgical repair was performed through the right fourth intercostal space with the patient supine. The anomalous vein was divided and interposed with a short azygos vein graft, followed by closure of the VSD. Finally, the interposed azygos vein was anastomosed to the left atrium. Although pulmonary artery pressure was normalized at the 2-year follow-up, cardiac catheterization 6 months after the operation demonstrated right pulmonary vein obstruction.
    No preview · Article · Oct 2010 · General Thoracic and Cardiovascular Surgery

  • No preview · Article · Jan 2010
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    ABSTRACT: Pulmonary ischemia and reperfusion during routine open heart surgery with cardiopulmonary bypass can lead to pulmonary dysfunction and vasoconstriction, resulting in a high morbidity and mortality. We investigated whether ischemia/reperfusion-induced pulmonary dysfunction after full-flow cardiopulmonary bypass could be prevented by the infusion of leukocyte-depleted hypoxemic blood during the early phase of reperfusion (terminal leukocyte-depleted lung reperfusion) and whether the benefits of this method were nullified by using hyperoxemic blood for reperfusion. Twenty-one neonatal piglets underwent 180 minutes of full-flow cardiopulmonary bypass with pulmonary artery occlusion, followed by reperfusion. The piglets were divided into 3 groups of 7 animals. In group I, uncontrolled reperfusion was achieved by unclamping the pulmonary artery. In contrast, pulmonary reperfusion was done with leukocyte-depleted hyperoxemic blood in group II or with leukocyte-depleted hypoxemic blood in group III for 15 minutes at a flow rate of 10 mL/min/kg before pulmonary artery unclamping. Then the animals were monitored for 120 minutes to evaluate post-cardiopulmonary bypass pulmonary function. Group I developed pulmonary dysfunction that was characterized by an increased alveolar-arterial oxygen difference (204 + or - 57.7 mm Hg), pulmonary vasoconstriction, and decreased static lung compliance. Terminal leukocyte-depleted lung reperfusion attenuated post-cardiopulmonary bypass pulmonary dysfunction and vasoconstriction when hypoxemic blood was used for reperfusion (alveolar-arterial oxygen difference, 162 + or - 61.0 mm Hg). In contrast, no benefit of terminal leukocyte-depleted lung reperfusion was detected after reperfusion with hyperoxemic blood (alveolar-arterial oxygen difference, 207 + or - 60.8 mm Hg). Reperfusion with leukocyte-depleted hypoxemic blood has a protective effect against ischemia/reperfusion-induced pulmonary dysfunction by reducing endothelial damage, cytokine release, and leukocyte activation.
    No preview · Article · Nov 2009 · The Journal of thoracic and cardiovascular surgery
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    ABSTRACT: Phosphodiesterase (PDE) III inhibitors have been reported in various cellular protective activities via the cyclic adenosine monophosphate (cAMP) pathway. We investigated the effects of amrinone on ischemia/reperfusion injury and intracellular calcium (Ca2+) handling if utilized as a component of terminal warm blood cardioplegia (TWBCP). Anesthetized pig hearts were subjected to 90-min global ischemia with single-dose crystalloid cardioplegia, followed by 30-min reperfusion under cardiopulmonary bypass. The animals were divided into three groups according to the contents of TWBCP (n = 5 each): Control, no TWBCP; TWBCP, no additive; Amrinone, TWBCP with amrinone. The time course of cardiac function and biochemical samples were measured. Further, coronary perfusion and ventricular arrhythmia were evaluated during reperfusion. Cardiac function improved with amrinone. Specifically, the amrinone group showed an increase of myocardial cAMP (p <0.05) and a suppression of creatine kinase, troponin-T, and lipid peroxide after reperfusion (p <0.05); many cases also showed much improvement of coronary perfusion and spontaneous resuscitation after global ischemia. Ischemia and/or reperfusion deplete myocardial cAMP, leading to impaired Ca2+ handling and further to cardiac dysfunction. High-dose PDEIII inhibitor in TWBCP may replenish myocardial cAMP and promote rapid and sustained cardiac functional recovery with various cellular protective effects after open-heart surgery.
    Preview · Article · Oct 2009
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    ABSTRACT: The Taussig-Bing malformation was originally described as a double-outlet right ventricle and a subpulmonic ventricular septal defect. We report on secondary surgery to repair this malformation. Because of pulmonary hypertension, we first performed pulmonary banding for palliation. After palliation, we performed the Kawashima operation for the Taussig-Bing malformation. The Kawashima method included intraventricle rerouting and was effective for repair of the double-outlet right ventricle of the Taussig-Bing malformation.
    No preview · Article · Mar 2009
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    ABSTRACT: An infant with type 3e truncus arteriosus (Collett and Edwards classification) is described. The base of the anomaly is the right aortic arch, the left pulmonary artery arises from the truncus, and the right pulmonary artery originates from a ductus arteriosus. A chromosome 22q11.2 deletion was present. To our knowledge, this malformation has not been described previously. Because the pulmonary arteries were small, we performed palliative surgery twice with the Rastelli procedure.
    No preview · Article · Mar 2009
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    ABSTRACT: A 71-year-old man required tricuspid valvuloplasty when an infected pacemaker lead was removed because of septicemia or bacteremia. The septicemia was caused by methicillin-resistant Staphylococcus epidermidis. The pacemaker endocardial lead and generator were removed under cardiopulmonary bypass. Because the lead was strongly adherent to the tricuspid leaflet, we partially resected the posterior leaflet. To eliminate any artificial device inside the heart and vessels, we implanted a myocardial screw-in lead in the epicardium. After the surgery, we were able to control the infection. Complete removal of a contaminated pacemaker system under cardiopulmonary bypass was effective.
    No preview · Article · Jan 2009

  • No preview · Article · Jan 2009
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    ABSTRACT: This study was performed to identify risk factors for hospital death in patients with acute and active infective endocarditis (AAIE) after surgical intervention. From 1980 to 2004, 94 patients underwent surgery for AAIE (age range, 3-77 years; 76% males). Congestive heart failure (CHF) was present in 44 patients, as well as vegetations in 64, septicemia in 16, abscesses in 17, and emboli in 22; 16 patients had prosthetic valve endocarditis. Streptococci were the most common bacteria (34 patients), followed by staphylococci (17 patients). Mechanical valves were selected for 73 patients and bioprosthetic valves for 16. Mitral valve plasty was performed in 4 patients. Aortic root or aorto-mitral discontinuity was repaired in 17 patients, including Manouguian's double valve replacement in 6 and aortic root replacement in 4. Overall hospital mortality was 15% (14 patients). Univariate analysis identified CHF (p=0.016), abscess (p=0.014), and prosthetic valve endocarditis (p=0.043) as risk factors. However, multivariate analysis only identified CHF (p=0.019) as an independent risk factor. In AAIE, early surgical intervention is advisable before the occurrence of complications such as root abscess and CHF, particularly before the onset of CHF.
    No preview · Article · Jan 2009 · Circulation Journal