37 results on '"Fukumura, F."'
Search Results
2. EFFECTS OF INTRA-AORTIC BALLOON PUMPING ON RENAL SYMPATHETIC NERVE ACTIVITY IN ACUTE HEART FAILURE
- Author
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Tokunaga, S., primary, Tominaga, R., additional, Nakano, T., additional, Fukae, K., additional, Fukumura, F., additional, Kawachi, Y., additional, and Yasui, H., additional
- Published
- 1996
- Full Text
- View/download PDF
3. COMPARATIVE STUDY OF SURFACE BLOOD INTERACTION TO CARDIOPULMONARY BYPASS CIRCUIT WITH OR WITHOUT HEPARIN-COATING
- Author
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Fukumura, F., primary, Nakashima, A., additional, Tomita, Y., additional, Toshima, Y., additional, Imoto, Y., additional, Morita, S., additional, Tominaga, R., additional, and Yasui, H., additional
- Published
- 1996
- Full Text
- View/download PDF
4. Elgiloy stent wire fracture as a cause of valve dysfunction in Carpentier-Edwards pericardial (CEP) valves
- Author
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Tominaga, R., primary, Fukumura, F., additional, Tomita, Y., additional, Toshima, Y., additional, Imoto, Y., additional, Masuda, M., additional, Morita, S., additional, and Yasui, H., additional
- Published
- 1996
- Full Text
- View/download PDF
5. Effects of diltiazem and noradrenaline on extracellular potassium changes in the globally ischaemic rat heart
- Author
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Mitani, A., primary, Kinoshita, K., additional, Fukamachi, K., additional, Sakamoto, M., additional, Kurisu, K., additional, Fukumura, F., additional, Tsuruhara, Y., additional, Nakashima, A., additional, and Tokunaga, K., additional
- Published
- 1992
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- View/download PDF
6. Effects of glibenclamide and nicorandil on cardiac function during ischemia and reperfusion in isolated perfused rat hearts
- Author
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Mitani, A., primary, Kinoshita, K., additional, Fukamachi, K., additional, Sakamoto, M., additional, Kurisu, K., additional, Tsuruhara, Y., additional, Fukumura, F., additional, Nakashima, A., additional, and Tokunaga, K., additional
- Published
- 1991
- Full Text
- View/download PDF
7. Characteristics of mixed crystals Co(1−x)FexSO4· 7H2O
- Author
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Fukumura, F. and Kobayashi, T.
- Abstract
The characteristics of the mixed crystal (Fe,Co)SO
4 ·7H2 O (x=Fe/(Fe+Co)) are studied from the Mössbauer spectroscopy. They are quite similar atx>0.3 to those of FeSO4 ·7H2 O. Whenx decreases from 0.2, the characteristics deviate from those of FeSO4 ·7H2 O and approach gradually to those of CoSO4 ·7H2 O.- Published
- 1986
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8. Postoperative Cardiac Rhythms With Superior-Septal Approach and Lateral Approach to the Mitral Valve
- Author
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Masuda, M., Tominaga, R., Kawachi, Y., Fukumura, F., Morita, S., Imoto, Y., Toshima, Y., Tomita, Y., and Yasui, H.
- Published
- 1996
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9. Preoperative Autologous Blood Donations in Pediatric Cardiac Surgery
- Author
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Masuda, M., Kawachi, Y., Inaba, S., Matsuzaki, K., Fukumura, F., Morita, S., Tominaga, R., and Yasui, H.
- Published
- 1995
- Full Text
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10. Author Correction: HOIL-1L deficiency induces cell cycle alteration which causes immaturity of skeletal muscle and cardiomyocytes.
- Author
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Akagi K, Baba S, Fujita H, Fuseya Y, Yoshinaga D, Kubota H, Kume E, Fukumura F, Matsuda K, Tanaka T, Hirata T, Saito MK, Iwai K, and Takita J
- Published
- 2024
- Full Text
- View/download PDF
11. HOIL-1L deficiency induces cell cycle alteration which causes immaturity of skeletal muscle and cardiomyocytes.
- Author
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Akagi K, Baba S, Fujita H, Fuseya Y, Yoshinaga D, Kubota H, Kume E, Fukumura F, Matsuda K, Tanaka T, Hirata T, Saito MK, Iwai K, and Takita J
- Subjects
- Animals, Humans, Mice, Cell Differentiation genetics, Cell Line, Muscle, Skeletal metabolism, Muscle, Skeletal pathology, Myocytes, Cardiac metabolism, Myocytes, Cardiac pathology, Transcription Factors genetics, Transcription Factors metabolism, Induced Pluripotent Stem Cells, Muscular Diseases metabolism, Muscular Diseases pathology, Ubiquitin-Protein Ligases genetics, Ubiquitin-Protein Ligases metabolism, Cell Cycle genetics
- Abstract
HOIL-1L deficiency was recently reported to be one of the causes of myopathy and dilated cardiomyopathy (DCM). However, the mechanisms by which myopathy and DCM develop have not been clearly elucidated. Here, we sought to elucidate these mechanisms using the murine myoblast cell line C2C12 and disease-specific human induced pluripotent stem cells (hiPSCs). Myotubes differentiated from HOIL-1L-KO C2C12 cells exhibited deteriorated differentiation and mitotic cell accumulation. CMs differentiated from patient-derived hiPSCs had an abnormal morphology with a larger size and were excessively multinucleated compared with CMs differentiated from control hiPSCs. Further analysis of hiPSC-derived CMs showed that HOIL-1L deficiency caused cell cycle alteration and mitotic cell accumulation. These results demonstrate that abnormal cell maturation possibly contribute to the development of myopathy and DCM. In conclusion, HOIL-1L is an important intrinsic regulator of cell cycle-related myotube and CM maturation and cell proliferation., (© 2024. The Author(s).)
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- 2024
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12. Bronchial Artery Aneurysm Treated Using Aortic Stent Graft Alone: A Case Report.
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Matsumoto T, Uchida T, Ono T, Hirayama K, Fukumura F, Ando H, and Tanaka J
- Abstract
A 72-year-old woman with a history of malignant lymphoma was referred to our hospital for the treatment of a bronchial artery aneurysm. Computed tomography (CT) scan showed a round, 30 mm-diameter fusiform aneurysm with two tortuous inflow arteries. We deployed thoracic stent grafting to cover the orifice of the two inflow arteries without transcatheter bronchial arterial embolization. Postoperative CT scan revealed complete thrombosis of the aneurysm. Although further follow-up is mandatory, this may be considered a viable treatment option in cases wherein the bronchial artery aneurysm is anatomically difficult to treat.
- Published
- 2017
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13. Endovascular Surgery for Traumatic Thoracic Aortic Injury: Our Experience with Five Cases, Two of Whom were Young Patients.
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Yamashita Y, Matsumoto T, Matsuyama S, Fukumura F, Ando H, Tanaka J, and Uchida T
- Abstract
Objectives: We present our experience of endovascular surgery for traumatic aortic injury and the results of our procedures., Materials and Methods: From January 2009 to December 2013, we performed endovascular repairs of traumatic thoracic aortic injury on 5 male patients 16-75 years old (mean, 50.8), two of whom were young. Three of the patients had multiple organ injuries. The mean interval time to the operation is 22.0 hours (range, 10-36). All patients underwent endovascular repair with heparinization. The isthmus regions were seen in three cases and all of them were needed left subclavian artery (LSA) coverage. In the two young patients, the deployed stent graft was 22 mm (22.2% oversizing for diameter of aorta) and 26 mm (36.8% oversizing), respectively., Results: The procedures were successful in all patients, with no early mortality, paraplegia or stroke. During 3-63 months (mean, 30.8) follow-up period, no one experienced stent graft-related complications. One patient with LSA coverage experienced arm ischemia but the symptom improved with time., Conclusion: Endovascular surgery for traumatic thoracic aortic injury can be performed safely with low mortality or morbidity even in young small aorta. Accumulation of clinical experience and evaluation of long-term outcomes are necessary.
- Published
- 2014
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14. [Arch aneurysm and ruptured innominate artery aneurysm with acute occlusion of trachea].
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Uchida T, Ando H, Yasutsune T, Izumo A, Fukumura F, and Tanaka J
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- Acute Disease, Aged, 80 and over, Female, Humans, Aneurysm, False complications, Aneurysm, Ruptured complications, Aortic Aneurysm, Thoracic complications, Brachiocephalic Trunk, Tracheal Stenosis etiology
- Abstract
We reported on a case of 80-year-old woman who suffered from severe acute respiratory failure. A chest computed tomography (CT) revealed arch aneurysm and innominate artery pseudoaneurysm, which severely compressed main bronchus and trachea. After tracheal intubation in the emergency room, respiratory status improved rapidly. We immediately performed total arch replacement using deep hypothermia, circulatory arrest and the arch first technique. The postoperative course was uneventful, and stenosis of trachea resolved. Arch aneurysm associated with acute trachea occlusion is very rare and employing deep hypothermia, circulatory arrest and the arch first technique is useful for such atypical arch aneurysms.
- Published
- 2011
15. [Thoracic aortic aneurysm due to giant cell arteritis without any specific symptom].
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Uchida T, Andou H, Yasutsune T, Iwai T, Fukumura F, and Tanaka J
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- Aged, Aortic Valve Insufficiency etiology, Diagnosis, Differential, Diagnostic Imaging, Female, Giant Cell Arteritis pathology, Humans, Aortic Aneurysm, Thoracic etiology, Aortic Aneurysm, Thoracic surgery, Giant Cell Arteritis complications, Giant Cell Arteritis diagnosis
- Abstract
A 76-year-old female was admitted to our hospital for investigation and treatment of aortic regurgitation. She was found to have an ascending aortic aneurysm extending to the proximal arch. She had not suffered from any symptoms except chest discomfort. Total arch replacement and aortic valvoplasty were performed under cardiopulmonary bypass. Pathological examination of the aneurismal wall revealed giant cell arteritis. Aortic aneurysm due to giant cell aortitis without such symptom as temporal pain or polymyalgia was considered to be very rare.
- Published
- 2009
16. [Gigantic coronary aneurysm arisen from coronary fistula between the left circumflex artery and the left ventricle].
- Author
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Uchida T, Andou H, Yasutsune T, Iwai T, Fukumura F, and Tanaka J
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- Aged, Coronary Aneurysm surgery, Coronary Disease surgery, Fistula surgery, Heart Diseases surgery, Heart Ventricles, Humans, Male, Vascular Fistula surgery, Coronary Aneurysm etiology, Coronary Disease complications, Fistula complications, Heart Diseases complications, Vascular Fistula complications
- Abstract
A 71-year-old male was referred to our hospital due to abnormality detected by a chest roentgenogram. He had no symptoms except for slight chest oppression. He was found to have a giant coronary aneurysm. It was originated from a coronary artery (left circum flex branch) left ventricular fistula. The orifice of this fistula to the left ventricle was also dilated and formed diverticulum. Ligation of the feeding coronary branch, closure of the aneurysmal fistula in the left ventricular wall and aneurysmectomy were performed under cardiopulmonary bypass. Postoperative course was uneventful. A giant aneurysm originated from a coronary-left ventricular fistula was considered to be very rare.
- Published
- 2008
17. [Two-stage repair of the transposition of great arteries with interruption/coarctation of the aorta].
- Author
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Fukumura F, Sese A, Ueno Y, Imoto Y, Sakamoto M, Ochiai Y, Iwai T, and Joho K
- Subjects
- Aorta, Thoracic surgery, Aortic Coarctation complications, Double Outlet Right Ventricle complications, Double Outlet Right Ventricle surgery, Humans, Infant, Infant, Newborn, Transposition of Great Vessels complications, Aorta, Thoracic abnormalities, Aortic Coarctation surgery, Cardiac Surgical Procedures methods, Transposition of Great Vessels surgery
- Abstract
We report on 10 patients who underwent two-stage repair of transposition of the great arteries (TGA) with interruption (IAA) or coarctation (CoA) of the aorta. First, an operation for aortic arch reconstruction was performed: Blalock-Park with pulmonary artery banding (PAB) for IAA (5 patients), subclavian flap with PAB for CoA (4 patients) and end-to-end anastomosis without PAB (1 patient). All survived the first operation and had no significant pressure gradient with good growth of the ascending aorta, except for the 1 case without PAB. Half of the 8 patients who underwent PAB developed migration of the PAB. The arterial switch operation (ASO) was performed 0.7-12.6 (5.6+/-4.7) months after the first surgery. One patient with an abnormal coronary artery tract was lost after ASO. Five developed pulmonary artery stenosis and 1 developed supra-aortic stenosis late after ASO. Two patients need reoperation, 1 for supra-aortic stenosis, and the other for reCoA. Two-stage repair for TGA with IAA/CoA is still a useful method with a good operative result. However, strict follow-up is necessary because of the high frequency of late morbidity.
- Published
- 2005
18. Comparison of pulsatile and non-pulsatile cardiopulmonary bypass on regional renal blood flow in sheep.
- Author
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Nakamura K, Harasaki H, Fukumura F, Fukamachi K, and Whalen R
- Subjects
- Animals, Blood Pressure physiology, Female, Models, Animal, Models, Cardiovascular, Perfusion, Regional Blood Flow physiology, Renal Circulation physiology, Sheep, Cardiopulmonary Bypass, Kidney Cortex blood supply, Pulsatile Flow physiology
- Abstract
Objective: The purpose of the present study was to evaluate the effects of pulsatile cardiopulmonary bypass (CPB) on sheep regional renal blood flow by comparing pulsatile and non-pulsatile perfusion at two different flow rates., Design: Seven female Suffolk sheep were used and the animals were perfused with pulsatile and non-pulsatile CPB at flow rates of 60 and 100 ml/min/kg. Regional renal blood flow was measured by the colored microsphere method. General linear model ANOVA was performed to analyze the data., Results: Regional renal blood flow was significantly higher in both outer and middle cortices of pulsatile CPB compared with non-pulsatile CPB (outer cortex: pulsatile CPB, 381+/-192 ml/min/100 g, non-pulsatile CPB, 255+/-151 ml/min/100g, p=0.002; middle cortex: pulsatile CPB, 239+/-114 ml/min/100 g, non-pulsatile CPB, 176+/-80 ml/min/100 g, p=0.02). The increase of flow rate from 60 to 100 ml/min/kg improved renal cortical blood flow significantly., Conclusion: The regional renal blood flow was significantly higher in both outer and middle cortices of pulsatile CPB compared with the non-pulsatile CPB.
- Published
- 2004
- Full Text
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19. Usefulness of low-priming-volume cardiopulmonary bypass circuits and dilutional ultrafiltration in neonatal open-heart surgery.
- Author
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Fukumura F, Kado H, Imoto Y, Shiokawa Y, Minami K, Murakami J, and Yasui H
- Subjects
- Hemodilution, Humans, Infant, Newborn, Respiration, Artificial, Transposition of Great Vessels surgery, Ultrafiltration, Cardiac Surgical Procedures, Cardiopulmonary Bypass
- Abstract
In neonate open-heart surgery, cardiopulmonary bypass (CPB) with extreme hemodilution induces an increased capillary permeability and accumulation of extravascular fluid, resulting in organ dysfunction. We evaluated the effects of a reduced priming volume for CPB and dilutional ultrafiltration (DUF) during neonatal open-heart surgery. Nineteen consecutive neonates with complete transposition of the great arteries who underwent an arterial switch operation were retrospectively assigned into two groups: the high-priming-volume circuit group (group A, n = 9) and the low-priming-volume circuit group (group B, n = 10). Patients in group B underwent surgery with a miniaturized CPB circuit and using the DUF technique. The priming volume of group B was nearly two-thirds that of group A. The water balance value after CPB and surgery was significantly lower in group B (-126 +/- 118 ml, -116 +/- 116 ml) than in group A (88 +/- 218 ml, 83 +/- 165 ml). Systolic blood pressure just after CPB was higher in group B (67.9 +/- 9.1 mmHg) than in group A (55.4 +/- 10.3 mmHg). Postoperative ventilatory support was shorter in group B (45 +/- 19 h) than in group A (68 +/- 27 h). In neonatal cardiac surgery, low-priming-volume CPB circuits and DUF improve the water balance during surgery and may attenuate any inflammatory reaction, which would help preserve postoperative organ function.
- Published
- 2004
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20. Haemostatic profile of small children during and following cardiopulmonary bypass.
- Author
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Fukumura F, Sese A, Ueno Y, Imoto Y, Sakamoto M, Tanoue Y, and Sonoda H
- Subjects
- Blood Coagulation Tests, Cardiac Surgical Procedures, Humans, Infant, Platelet Function Tests, Cardiopulmonary Bypass, Heart Defects, Congenital blood, Heart Defects, Congenital surgery, Hemostasis physiology
- Abstract
Objective: We evaluated changes of the haemostatic system during pediatric cardiac surgery during and after cardiopulmonary bypass (CPB)., Method: Twenty-five children under 15 kg of body weight undergoing open-heart surgery were divided into three groups; 9 patients (Group A), no bank blood was used throughout the surgery; 8 patients (Group B), packed red cells were used in the priming of CPB circuit; 8 patients (Group C) in cyanotic condition, for whom surgery was performed without bank blood. CPB caused a significant decrease of platelet counts in all three groups, the levels of which remained similar next morning., Results: Platelet counts decreased more significantly in Group C (59+/-27 k/mm3) than in Group A (119+/-42 k/mm3) and B (104+/-27 k/mm3). Platelet function-platelet activating factor test (HemoSTATUS) did not significantly decrease throughout the perioperative period in Group A. HemoSTATUS value decreased during CPB and recovered after CPB in Group B and C. Prothrombin time international ratio (PT-INR) and activated partial thromboplastin time were significantly prolonged just after CPB and recovered until next morning in all three groups. PT-INR was more prolonged in Group C (2.92+/-0.62) than in Group A (2.08+/-0.27) and B (2.42+/-0.42). There was no significant difference in postoperative bleeding for the first 12 hours among the three groups., Conclusion: Although extreme hemodilution during CPB significantly impairs the coagulation and platelet system, these changes are usually transient and tolerable with minimal postoperative hemorrhage. However, a prolonged CPB and preoperative cyanotic condition may induce a critical decrease of platelet counts and increase postoperative bleeding.
- Published
- 2003
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21. Ventricular energetics in endoventricular circular patch plasty for dyskinetic anterior left ventricular aneurysm.
- Author
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Tanoue Y, Ando H, Fukumura F, Umesue M, Uchida T, Taniguchi K, and Tanaka J
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- Adult, Aged, Cardiac Surgical Procedures methods, Female, Humans, Male, Middle Aged, Myocardial Infarction complications, Retrospective Studies, Heart Aneurysm surgery, Heart Ventricles surgery, Ventricular Dysfunction, Left surgery, Ventricular Function, Ventricular Function, Left physiology
- Abstract
Background: The endoventricular circular patch plasty (Dor procedure) applies to patients with a left ventricular dysfunction due to an ischemic dilated ventricle. In the present study, we analyzed left ventricular energetics in patients who underwent the Dor procedure., Methods: We measured left ventricular contractility (end-systolic elastance; Ees), afterload (effective arterial elastance; Ea), and efficiency (ventriculoarterial coupling; Ea/Ees, and the ratio of stroke work and pressure-volume area; SW/PVA) based on the cardiac catheterization data before and after the Dor procedure in 8 patients with a postinfarction dyskinetic anterior left ventricular aneurysm. Concomitant procedures included coronary artery bypass grafting in all patients, mitral valve repair in one patient, and cryoablation in one patient. End-systolic elastance (Ees) and Ea were approximated as follows: Ees = mean arterial pressure/minimal left ventricular volume, and Ea = maximal left ventricular pressure/(maximal left ventricular volume-minimal left ventricular volume), and thereafter Ea/Ees and SW/PVA were calculated. The left ventricular volume was normalized with the body surface area., Results: End-systolic elastance (Ees) increased after the Dor procedure (from 1.15 +/- 0.60 to 1.86 +/- 0.84 mm Hg x m2 x mL(-1), p < 0.01), thus resulting in an improvement in Ea/Ees and SW/PVA (from 2.94 +/- 1.11 to 1.64 +/- 0.49, p < 0.01, and from 0.426 +/- 0.110 to 0.559 +/- 0.082, p < 0.01, respectively), even though Ea did not substantially change (from 2.96 +/- 0.78 to 2.74 +/- 0.55 mm Hg x m2 x mL(-1), p = 0.4)., Conclusions: Left ventricular contractility and efficiency improves after the Dor procedure in patients with a dyskinetic anterior left ventricular aneurysm. However, afterload does not change. The use of appropriate afterload-reducing therapy thus plays an especially important role in the management of patients who undergo the Dor procedure.
- Published
- 2003
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22. [Surgical treatment of mitral valve prolapse using the mitral apparatus to adjust proper length of artificial chordae].
- Author
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Yasui H, Tomita Y, Imoto H, Tomihaga T, Morita S, Toshima Y, and Fukumura F
- Subjects
- Humans, Male, Middle Aged, Mitral Valve pathology, Mitral Valve Prolapse pathology, Chordae Tendineae surgery, Heart Valve Prosthesis Implantation methods, Mitral Valve surgery, Mitral Valve Prolapse surgery
- Published
- 1998
23. [Questionnaire of cryopreserved allograft valves in Kyushu and Yamaguchi area].
- Author
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Tokunaga S, Morita S, Tomita Y, Toshima Y, Masuda M, Imoto Y, Fukumura F, Nakano T, Tominaga R, Kawachi R, and Yasui H
- Subjects
- Humans, Japan, Surveys and Questionnaires, Tissue Donors supply & distribution, Transplantation, Homologous, Attitude to Health, Cryopreservation, Heart Valves
- Abstract
Japanese Society of Cryopreserved Thoracic Tissue Implantation was recently set up. Cryopreserved allograft valves are about to pervade in Japan. To clarify the interest, demands and supply of cryopreserved allograft valve in the area of Kyushu and Yamaguchi, we performed questionnaire investigation regarding this issue. Collection rate of this questionnaire was 87.5% (35/40 hospitals). Ninety-seven percent of the hospitals answered that they were interested in cryopreserved allograft. Ninety-four percent of the hospitals answered that they did not ethically hesitate to use cryopreserved allograft. Ninety-one percent of the hospitals hoped to perform cardiac surgery using allograft aortic valve if allograft is available. With respect to securing donors of allograft, two-third of the hospitals did not decide whether they could be involved in obtaining donors of allograft. As the number of the cadaver kidney donors is about 20 per year in the area of Kyushu and Yamaguchi, shortage of donors of allograft valve is anticipated.
- Published
- 1996
24. [Intracardiac foreign bodies].
- Author
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Masuda M and Fukumura F
- Subjects
- Humans, Foreign Bodies, Heart
- Published
- 1996
25. The Cleveland Clinic-Nimbus total artificial heart. In vivo hemodynamic performance in calves and preclinical studies.
- Author
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McCarthy PM, Fukamachi K, Fukumura F, Muramoto K, Golding LA, and Harasaki H
- Subjects
- Animals, Cattle, Evaluation Studies as Topic, Heart Transplantation, Hemodynamics, Humans, Male, Materials Testing, Physical Exertion, Heart, Artificial
- Abstract
In vitro function of the Cleveland Clinic-Nimbus electrohydraulic total artificial heart met National Heart, Lung, and Blood Institute hemodynamic guidelines for such devices. In a series of in vivo experiments, we implanted the total artificial heart in eight calves (mean weight 87 kg), one for a short-term experiment and seven for long-term experiments. The mean blood flow during support was 7.7 +/- 1.6 L/min with left atrial pressure 13 +/- 6 mm Hg, right atrial pressure 13 +/- 4 mm Hg, and aortic pressure 97 +/- 9 mm hg. Maximum pump flow (9.6 L/min) occurred after 4 days of support as a result of the high resting cardiac output of the animals. A 10% to 15% right pump stroke-volume limit effectively balanced atrial pressures, and afterload insensitivity was confirmed by the in vivo studies. Calves tolerated treadmill exercise studies well, with an average duration of 22 minutes and an average top speed of 2.1 mph. The experiments were terminated after 1 day to 120 days of support (mean 32 days). Most experiments were terminated as a result of correctable mechanical problems. In a separate study of six adult human patients undergoing orthotopic cardiac transplantation, five showed an excellent fit for the Cleveland Clinic-Nimbus total artificial heart. Further studies using chest roentgenograms, chest measurements, and transesophageal echocardiography should help predict fit of the total artificial heart in potential candidates. Initial candidates for a "vented-electric" version of the Cleveland Clinic-Nimbus total artificial heart are patients for whom univentricular (left ventricular assist device) support is not appropriate, but who require mechanical support as a bridge to cardiac transplantation.
- Published
- 1994
26. Progress in Cleveland Clinic-Nimbus total artificial heart development.
- Author
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Harasaki H, Fukamachi K, Massiello A, Chen JF, Himley SC, Fukumura F, Muramoto K, Niu S, Wika K, and Davies CR
- Subjects
- Animals, Biomedical Engineering, Cardiac Output, Cattle, Embolism etiology, Evaluation Studies as Topic, Hemodynamics, Hot Temperature adverse effects, Mycoses etiology, Heart, Artificial adverse effects
- Abstract
A totally implantable, Cleveland Clinic-Nimbus total artificial heart (TAH) uses electrohydraulic energy conversion and an automatic left master-alternate mode control scheme, with a filling sensitivity of 1.0 l/min/mmHg and a maximum output of 9.5 l/min. The TAHs were tested in 12 calves for 1-120 days with normal major organ and blood cell function. Post-operative suppression of platelet aggregation recovered by the second post-operative week. The gelatin-coated pump surface generally was clean without any anticoagulants and free from infection. Embolism, which occurred in two cases, was caused by complications attributable to fungal infection in a Dacron graft and by thrombus formed around a jugular vein catheter. A system with a hybridized microcircuit controller in the interventricular space has been tested successfully in the three most recent cases, with a peak device surface temperature elevation of 6.5 degrees C. Heat effects were confined to the tissues immediately adjacent to the hottest spots. The carbon fiber-reinforced epoxy housing and 60 ml butyl rubber compliance chamber showed good tissue compatibility with a thin, fibrous tissue capsule. The transcutaneous energy transmission system and the internal battery functioned well as designed in the most recent animal implant.
- Published
- 1994
27. Adaptation of tissue to a chronic heat load.
- Author
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Davies CR, Fukumura F, Fukamachi K, Muramoto K, Himley SC, Massiello A, Chen JF, and Harasaki H
- Subjects
- Animals, Biomedical Engineering, Body Temperature, Cattle, Evaluation Studies as Topic, Lung physiology, Muscles physiology, Neovascularization, Physiologic, Thermometers, Time Factors, Adaptation, Physiological, Heart, Artificial adverse effects, Hot Temperature adverse effects
- Abstract
Determination of the chronic effect of heat on tissue is one of the important issues facing mechanically actuated total artificial heart (TAH) development. In an effort to characterize this effect, implantations of heating devices producing constant heat fluxes of 0.04 watts/cm2, 0.06 W/cm2, and 0.08 W/cm2 were performed in 11 calves (H-series). Heated disks were implanted adjacent to lung and muscle tissue for a period of 7 weeks. Temperature sensors were placed at the surface as part of the heater assemblies. The results showed that initially, temperature elevations above body temperature (delta T) were 6.4 +/- 0.6 degrees C, 4.5 +/- 0.2 degrees C, and 1.8 +/- 0.5 degrees C at the muscle heater surface for 0.08, 0.06, and 0.04 W/cm2, respectively. At 2 weeks after implant delta T values changed to 5.5 +/- 0.6 degrees C, 3.4 +/- 0.2 degrees C, and 1.8 +/- 0.2 degrees C, respectively. Seven weeks after implant, delta T values decreased to 3.7 +/- 1.2 degrees C, 2.8 +/- 0.1 degrees C, and 0.8 degrees C for 0.08, 0.06, and 0.04 W/cm2, respectively. The authors think this change is attributable to an adaptive response of the tissue to increase heat dissipation through angiogenesis. Results from three TAH cases indicated that at two measured tissue interfaces, delta T decreased by 1 degrees C during a 15 day period. At the same time, the waste heat (volts x current in-flow x afterload to the blood) remained constant at 11.1 +/- 0.5 W during this period. This decrease in delta T corresponded to that observed for the H-series experiments at the higher heat fluxes. Thus, it appears that adaptation observed in the H-series experiments also is seen for tissues surrounding heat sources such as the TAH.
- Published
- 1994
- Full Text
- View/download PDF
28. The effects of radiation therapy on the tissue capsule of soft tissue implants.
- Author
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Whalen RL, Bowen MA, Fukumura F, Fukamachi K, Muramoto K, Higgins P, Brown J, and Harasaki H
- Subjects
- Animals, Biocompatible Materials radiation effects, Connective Tissue pathology, Connective Tissue radiation effects, Connective Tissue surgery, Female, Humans, Materials Testing, Microscopy, Electron, Rabbits, Radiotherapy Dosage, Silicone Elastomers radiation effects, Breast, Breast Neoplasms radiotherapy, Breast Neoplasms surgery, Mastectomy, Segmental, Prostheses and Implants adverse effects
- Abstract
A prosthesis has been developed for cosmesis after lumpectomy surgery for breast carcinoma. The device is saline filled and percutaneously adjustable in volume to permit an optimal cosmetic result after surgical wound healing. A series of 24 studies of 18 weeks' duration using the adult rabbit animal model were first used to study tissue capsule formation around textured versus smooth surface control implants and to evaluate the effects of volume adjustments on the tissue capsule. Single or multiple adjustments of implant volume had no effect on tissue capsule thickness or morphology. Because lumpectomy surgery is invariably followed by radiation therapy, a series of six studies was then conducted to determine the effects of a typical course of radiation therapy on tissue capsule formation. One week after device implantation, a 4 x 4 cm field including the implant was irradiated with 5,000 rad (200 rad/day x 5 days/week x 5 weeks). The animals were maintained for a 6 week period after radiation treatment. After sacrifice, the implants were removed, and the tissue capsules studied using conventional histologic techniques, including scanning and transmission electron microscopy. There was no statistically significant difference in tissue capsule thickness compared to nonirradiated controls. Tissue capsule morphology, however, differed markedly. Radiation therapy decreased angiogenesis, cellularity, and the inflammatory cell response to the implants. Qualitatively, radiation treatment seemingly improved rather than compromised the connective tissue response to the implants.
- Published
- 1994
- Full Text
- View/download PDF
29. Effects of a total artificial heart right stroke volume limiter on left-right hemodynamic balance.
- Author
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Fukamachi K, Massiello AL, Kiraly RJ, Chen JF, Himley S, Davies C, Fukumura F, Muramoto K, Olsen E, and Golding LA
- Subjects
- Animals, Blood Pressure physiology, Cardiac Output physiology, Cattle, Equipment Design, Models, Cardiovascular, Heart, Artificial, Hemodynamics physiology, Stroke Volume physiology, Ventricular Function, Left physiology, Ventricular Function, Right physiology
- Abstract
In a completely implantable total artificial heart (TAH), the left-right flow difference attributable to higher volumetric efficiency of the right pump and bronchial artery shunting has always been a significant problem. The automatic control of the Cleveland Clinic-Nimbus TAH accommodates for the left-right flow difference when the beat rate is below maximum (AUTO range). However, at its maximum beat rate (MAX), high left atrial pressure (LAP) (greater than 25 mmHg) with relatively low right atrial pressure (RAP) (less than 8 mmHg) were observed both in vitro and in vivo, suggesting the need for a stroke volume limiter (SVL) of the right pump. In vitro volume loading tests showed 10%, 15%, and 20% SVLs prevented a disproportionate increase of LAP. In vivo studies in five Holstein calves also showed a balanced LAP-RAP relationship with 10% and 15% SVLs at MAX. The left pump flow was not affected by this range of SVLs either in vitro or in vivo. Pulmonary function was maintained with either size SVL, with autopsies revealing absence of pulmonary congestion and minimal pleural effusions in two calves surviving for more than 1 month. Although additional studies are needed to determine the appropriate size of the SVL, both 10% and 15% SVLs were effective in maintaining left-right hemodynamic balance in this TAH.
- Published
- 1993
30. A new finger joint prosthesis.
- Author
-
Whalen RL, Bowen MA, Sarrasin MJ, Fukumura F, and Harasaki H
- Subjects
- Animals, Biomechanical Phenomena, Knee Joint surgery, Materials Testing, Microscopy, Electron, Scanning, Models, Biological, Prosthesis Design, Rabbits, Range of Motion, Articular physiology, Surface Properties, Finger Joint surgery, Joint Prosthesis
- Abstract
A new finger joint prosthesis is being developed for the proximal and distal interphalangeal positions. Currently available "joint spacer" prostheses provide relief from pain and cosmetic improvement, but relatively poor long-term function. The new prosthesis employs a mechanical hinge at the joint. It is fabricated from titanium alloy (6A14V). The hinge mechanism avoids direct metal to metal contact by using high density polyethylene bearings. In vitro tests of the hinge mechanism have passed 75 million cycles of continuous flexure without failure (n = 12). The hinge also incorporates a mechanical limit stop to prevent hyperextension. The hinge mechanism is enclosed in a sealed elastomeric jacket that isolates the hinge from connective tissue ingrowth. The jacket, equivalent to an artificial synovial membrane, has an integrally textured exterior surface designed to promote tissue attachment to the implant to stabilize tissue capsule formation around the joint. To test the in vivo efficacy of the new design, a series of 12 devices were implanted in the knee joint position of adult rabbits. A jacketed prosthesis was implanted on one side, whereas 2 weeks later an unjacketed control was implanted contralaterally. The animals then were maintained for an 8 week period. At sacrifice, the implants were removed, and the response of the surrounding tissues was studied histologically. At the time of implantation, the range of motion of the joints was approximately 100-105 degrees. There was a progressive loss in range of motion observed in both groups. The fibrous tissue capsule around the jacketed implants, however, was significantly reduced in thickness compared with the controls (mean thickness, 1.5 mm vs. 4.5 mm).(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
31. Tranexamic acid reduces blood loss after cardiopulmonary bypass.
- Author
-
Nakashima A, Matsuzaki K, Fukumura F, Hisahara M, Kanegae Y, Fukae K, Miyamoto K, Nishida T, Tokunaga S, and Tominaga R
- Subjects
- Adult, Aged, Blood Loss, Surgical physiopathology, Female, Heart Valve Diseases blood, Humans, Male, Middle Aged, Oxygenators, Membrane, Tranexamic Acid adverse effects, Blood Loss, Surgical prevention & control, Cardiopulmonary Bypass, Heart Valve Diseases surgery, Premedication, Tranexamic Acid administration & dosage
- Abstract
To evaluate the effect of tranexamic acid (TA) on blood loss after cardiopulmonary bypass (CPB), 157 patients who underwent elective valve replacement operations were studied, with one group of 90 patients receiving tranexamic acid (Group TA) and 67 patients serving as the control group (Group N). In group TA, 50 mg/kg of tranexamic acid was administered just before and after CPB, and every 90 minutes during CPB. The activated coagulation time was maintained at more than 450 seconds during CPB in both groups. There was no significant difference in the CPB time between the groups (163 +/- 32 min in group N and 152 +/- 38 min in group TA:NS). The time required for hemostasis was shortened in group TA, which resulted in a shorter operation time (6.7 +/- 1.5 hrs vs 6.0 +/- 1.5 hrs in group N and group TA, respectively: p = 0.006). The amount of chest tube drainage within 12 hours after surgery was significantly reduced (225 +/- 129 ml vs. 180 +/- 118 ml in group N and group TA, respectively: p = 0.026). The chest tube was able to be removed earlier in group TA, and the total blood loss was significantly smaller in group TA (402 +/- 292 ml) than in group N (631 +/- 609 ml; p = 0.004). The authors thus conclude that antifibrinolytic therapy during CPB with tranexamic acid reduces postoperative blood loss, and shortens the operation time due to an improvement in hemostasis.
- Published
- 1993
32. Development of a magnetically operated artificial urethral sphincter. Chronic effects of compression on the skin structure and blood flow.
- Author
-
Fukumura F, Harasaki H, Fukamachi K, Muramoto K, Davies C, Brown JZ, Sarrasin MJ, and Whalen RL
- Subjects
- Animals, Necrosis, Pressure, Prosthesis Design, Regional Blood Flow physiology, Skin pathology, Swine, Swine, Miniature, Urethra pathology, Magnetics, Prostheses and Implants, Skin blood supply, Urethra blood supply, Urinary Sphincter, Artificial
- Abstract
The artificial urethral sphincter (AUS) has been in clinical use for more than 20 years. Currently available AUS devices, however, are difficult to use and not entirely reliable. A magnetically operated AUS is currently under the development. Although the skin between the magnets will be compressed all day long, little information exists on the effects of chronic pressure on the skin structure and blood flow. In five miniature pigs, two internal magnets and one control metal disk were implanted subcutaneously at three different positions, and external magnets with differing magnetic forces were applied to the skin overlying the internal magnets for six weeks. In four pigs, the skin blood flow was measured by a laser Doppler flow meter applying different pressures. Compression of 10 mmHg preserved normal skin morphology in all but one animal where blood flow had not recovered 2 weeks after surgery. Compression of 20 mmHg for 6 weeks, however, produced pressure ulcers in all five cases (p < 0.05 vs. 10 mmHg group). The skin blood flow declined for pressures exceeding 20 mmHg (0 mmHg: 4.3 +/- 1.2, 10 mmHg: 4.3 +/- 3.3, 20 mmHg: 2.6 +/- 2.7 ml/min/100 g). We concluded that the magnetically operated AUS should use a magnetic coupling with a pressure less than 10 mmHg exerted on the interposing skin.
- Published
- 1993
33. Hemodynamic changes with posture in calves with total artificial heart.
- Author
-
Fukamachi K, Fukumura F, Kiraly RJ, Massiello AL, Chen JF, Himley S, Davies C, Muramoto K, Olsen E, and Golding LA
- Subjects
- Animals, Blood Flow Velocity physiology, Blood Pressure physiology, Cardiac Output physiology, Cattle, Equipment Design, Heart Rate physiology, Heart, Artificial, Hemodynamics physiology, Posture physiology
- Abstract
Hemodynamic changes with posture, sitting versus standing, were analyzed in five Holstein calves with the Cleveland Clinic-Nimbus TAH. This total artificial heart (TAH) has a left master alternate control mode that adjusts the pump rate and consequently pump flow proportional to the pulmonary venous return to the left pump (AUTO period). However, in this series of experiments, the pump reached its maximum beat rate within 1-5 days post operatively, after which pump flow could not increase (MAX period). Hemodynamic parameters (RAP, LAP, PAP, AoP, and pump flow) were obtained every 15-20 min throughout the experiments for as long as 120 days and averaged for each posture for each period. During the AUTO period, the flow while standing was significantly higher than that while sitting (standing: 8.7 +/- 0.2 L/min; sitting: 7.5 +/- 0.4 L/min; p < 0.05), and the systemic vascular resistance (SVR) was significantly lower (standing: 895 +/- 93 dyne.sec.m-5; sitting: 1,041 +/- 124 dyne.sec.m-5; p < 0.05). During the MAX period, the AoP and SVR standing were significantly lower than those sitting (AoP standing: 91 +/- 7 mmHg; AoP sitting: 98 +/- 7 mmHg; p < 0.05; SVR standing: 652 +/- 75 mmHg; SVR sitting: 730 +/- 96 mmHg; p < 0.05). The Cleveland Clinic-Nimbus TAH responded well to these changes in position, increasing pump flow and maintaining the AoP during the AUTO period.
- Published
- 1993
- Full Text
- View/download PDF
34. Effects of pump flow rate on oxygen use during moderate hypothermic cardiopulmonary bypass.
- Author
-
Tominaga R, Kurisu K, Fukumura F, Nakashima A, Hisahara M, Siraishi K, Kawachi Y, Yasui H, and Tokunaga K
- Subjects
- Adult, Aged, Alprostadil pharmacology, Blood Gas Analysis, Coronary Artery Bypass, Heart Valve Diseases surgery, Hemodynamics drug effects, Humans, Hypothermia, Induced, Middle Aged, Cardiopulmonary Bypass, Oxygen Consumption drug effects
- Abstract
The authors investigated the effects of pump flow rate on oxygen use during a moderate hypothermic cardiopulmonary bypass (CPB) in 31 patients during either coronary artery bypass grafting or valve replacement and aortic cross clamping. Intravenous anesthesia was performed with high dose fentanyl. A neuromuscular blockade was achieved with an intravenous infusion of pancuronium. After a stable rectal temperature of 29 degrees C was obtained by both surface cooling with a blanket and core cooling with CPB, the pump flow rate was changed from 2.4 L/min/m2 to 2.2, 2.0, 1.8 and 1.6, keeping the same flow rate for at least 5 min. Both arterial and venous blood was sampled for blood gas analysis; serum lactate measurement and hemodynamic changes were monitored and recorded at each flow rate. In 10 of 31 patients, whose aortic cross clamping time was longer than 90 min, the same measurements were followed 10 min after the induction of prostaglandin E1 (PGE1) (40 +/- 13 ng/kg/min) at pump flow rates of 2.4, 2.0, and 1.6 L/min/m2. Oxygen consumption significantly decreased at 1.6 L/min/m2 compared to the other flow rates (52.4 +/- 13.6, 54.3 +/- 11.8, 56.4 +/- 14.7, and 56.7 +/- 11.0 ml/min/m2, at flow rates of 2.4, 2.2, 2.0 and 1.8 L/min/m2, respectively, versus 48.4 +/- 10.9 ml/min/m2, at 1.6 L/min/m2, p < 0.01, paired t-test). After the induction of PGE1, both aortic pressure and systemic vascular resistance decreased significantly (p < 0.01, paired t-test) at flow rates of 2.0 and 1.6 L/min/m2.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1993
35. [Clinical experience using albumin-containing crystalloid cardioplegia in open heart surgery in infancy].
- Author
-
Yonenaga K, Yasui H, Kado H, Ando H, Nakano E, Fukumura F, Masuda M, and Asou T
- Subjects
- Age Factors, Evaluation Studies as Topic, Heart Defects, Congenital surgery, Humans, Infant, Infant, Newborn, Potassium, Albumins, Heart Arrest, Induced methods, Potassium Compounds
- Published
- 1987
36. [Retrograde coronary sinus perfusion of cardioplegic solution in Jatene operation in neonates and infants].
- Author
-
Yonenaga K, Yasui H, Kado H, Andou H, Nakano E, Fukumura F, Nishimura Y, Zaitsu M, Shin T, and Morimoto A
- Subjects
- Evaluation Studies as Topic, Humans, Infant, Infant, Newborn, Potassium administration & dosage, Aorta surgery, Cardioplegic Solutions administration & dosage, Coronary Vessels surgery, Perfusion methods, Potassium Compounds
- Abstract
The clinical benefits of retrograde coronary sinus perfusion of a cardioplegic solution were investigated in 7 neonates and 23 infants undergoing Jatene operation. After an initial infusion of albumin-containing crystalloid cardioplegic solution via the aortic root, 21 patients received additional solution delivered by retrograde coronary sinus perfusion (retrograde group) and 9 patients received by selective antegrade coronary perfusion (antegrade group) every 20 to 30 minutes. There were no differences in age, weight, and left ventricular preoperative pressure and morphology between the two groups. Aortic cross-clamping time was 130 +/- 18 minutes in retrograde group and 147 +/- 20 minutes in antegrade group. Postoperative assays of CPK-MB, GOT and LDH, and hemodynamic measurements immediately after cessation of cardiopulmonary bypass (CPB) were carried out in all patients. Although there was no significant difference between the two groups in terms of enzyme indexes, retrograde group showed a greater variation of sigma CPK-MB from patient to patient than antegrade group. However, hemodynamic parameters of CVP, left atrial pressure and rate-pressure product at 20-30 minutes after CPB were similar in the two groups. Six neonates in retrograde group also demonstrated the similar enzyme indexes and hemodynamic state immediately after CPB to other older patients. We concluded, therefore, that retroperfusion of cardioplegic solution in neonates and infants provides satisfactory myocardial protection as well as antegrade perfusion, and it was a useful means of cardioplegic delivery in Jatene operation, because of its simplicity.
- Published
- 1989
37. [Early and late results of rereplacement of prosthetic heart valve--an analysis of risk factors].
- Author
-
Kawachi Y, Tominaga R, Kohno H, Kinoshita K, Yoshitoshi M, Fukumura F, Nakashima A, Tanaka J, and Tokunaga K
- Subjects
- Adolescent, Adult, Aged, Child, Child, Preschool, Female, Humans, Male, Middle Aged, Reoperation, Risk Factors, Heart Valve Prosthesis mortality
- Published
- 1988
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