Biomedical subjects

S Suehiro

Publications and source records attributed to S Suehiro.

At least 37 records · Page 2Linked to original sources

PubMed2000

Early surgery for active infective endocarditis.

OBJECTIVE: The timing of surgery for active infective endocarditis remains controversial. In this report, we have reviewed 26 patients who underwent surgery for active infective native-valve endocarditis between April 1992 and December 1998. PATIENTS AND METHOD: There were 19 male and 7 female patients (mean age 45 years). The aortic valve was involved in 8 patients, the mitral valve in 6 patients, tricuspid valve in 2 patients, both aortic and mitral valves in 7 patients, both aortic and tricuspid valve in 2 patients, and both mitral and tricuspid valve in one patient. The most common microorganisms were streptococcal species. Preoperative high New York Heart Association functional class (III and IV) was presented in 20 patients (77%). Progressive heart failure and the echocardiographic findings of vegetation (larger than 1 cm) were the main operative indications. Emergency or urgent surgery was required in 18 patients (70%). All patients underwent valve replacement, involving 25 mechanical prosthesis and 8 bioprosthesis. RESULTS: The operative mortality was 7.8% (n = 2). In the two patients who died, the infection had extended to the deep cardiac tissue and to the cerebral artery. The mean follow-up of the 24 survivors was 33 months (range from 6 to 82 months). There was no late death and no recurrence of infective endocarditis. CONCLUSION: In case of active infective endocarditis, early surgical intervention is recommended in patients with rapidly progressive cardiac deterioration or vegetation seen on echocardiography.

Adolescent↗

PubMed2000

Neointimal formation at the sites of anastomosis of the internal thoracic artery grafts after coronary artery bypass grafting in human subjects: an immunohistochemical analysis.

OBJECTIVES: The aim of this study was to evaluate the cellular composition and cell proliferative activity of neointimal tissue in human internal thoracic artery grafts and to characterize the differentiation state of neointimal smooth muscle cells at early stages after coronary artery bypass grafting. METHODS: The anastomotic sites and body segments of 7 patent grafts were obtained at autopsy from 7 patients who died within 92 days after operation. Serial sections were examined by immunohistochemical techniques to identify macrophages, endothelial cells, smooth muscle cell phenotype, and proliferating cells. For the identification of the cell types that show cell proliferative activity, immunodouble staining was also performed. RESULTS: In all body segments the luminal surface was completely covered by endothelial cells, and no areas showed thrombus formation or neointimal proliferation after grafting. In contrast, in the anastomotic segments endothelial denudation and focal disruption of the internal elastic lamina with adherence of fibrin-platelet thrombus and infiltration of macrophages were observed in the earliest stage after grafting. At these sites of injury, early neointimal tissue response had occurred, and cell proliferative activity was detected in macrophages and dedifferentiated smooth muscle cells. During the evolution of neointimal thickening, redifferentiation of neointimal smooth muscle cells occurred associated with the decline in proliferative activity. CONCLUSIONS: These observations strongly support the concept that excessive neointimal proliferation, which may occur at the site of anastomosis because of extensive damage to the arterial wall, could be one of the possible causes of failure of the internal thoracic artery graft in human beings.

Aged↗

PubMed2000

Role of endothelial cell denudation and smooth muscle cell dedifferentiation in neointimal formation of human vein grafts after coronary artery bypass grafting: therapeutic implications.

OBJECTIVE: To provide better insights into the genesis of neointimal thickening in human vein grafts early after surgery. DESIGN: Retrospective study. SETTING: Tertiary referral centre. SUBJECTS: 18 distal anastomotic sites of patent grafts, obtained at necropsy from eight patients who died over differing periods (ranging from two days to nine months) after the procedure. MAIN OUTCOME MEASURES: Immunohistochemical evaluation of smooth muscle cell phenotype modulation in relation to proliferative activity. RESULTS: The earliest changes are characterised by loss of surface lining endothelial cells and insudation of blood corpuscular elements admixed with fibrin-platelet thrombus. At sites of injury vimentin positive and actin negative spindle shaped cells appear in the intima, while the related pre-existent media shows focal absence of actin positive smooth muscle cells. Proliferative activity colocalises at these sites. With time distinct neointimal thickening occurs, associated with disappearance of proliferative activity and a phenotypic shift of the smooth muscle cells. CONCLUSIONS: The observation that luminal endothelial cell denudation, with insudation of the intima with blood elements, occurs in the very early stages suggests that these phenomena are responsible for the observed dedifferentiation of pre-existent smooth muscle cells, known to be a prerequisite for cell proliferation and the evolution of intimal thickening. It is likely, therefore, that platelet released growth factors play a pivotal role, which thus may provide a target for preventive pharmacological intervention.

Aged↗

PubMed2000

[A case of tricuspid infective endocarditis in a drug addict].

This report describes a successful operative case of tricuspid infective endocarditis in a drug addict. A 24-year-old man with a history of drug addiction (6 months) complained of general fatigue and high fever. Echocardiography showed a large vegetation attached to the tricuspid valve and severe tricuspid regurgitation. Blood cultures revealed septicemia due to methicillin sensitive Staphylococcus aureus. He was treated for about 1 week with intravenous antibiotics. However, subsequent severe heart failure necessitated emergency operation. The tricuspid valve was replaced with Carpentier-Edwards bioprosthesis because of severe destruction of the tricuspid valve. The postoperative course was uneventful and he has remained free from endocarditis for 15 months after surgery.

Adult↗

PubMed2000

[Successful aortic root replacement for prosthetic valve endocarditis using the freestyle stentless bioprosthesis: report of two cases].

We report two cases of prosthetic valve endocarditis which were successfully treated with aortic root replacement using the freestyle stentless bioprosthesis. Prosthetic valve endocarditis occurred in two patients after aortic valve replacement and modified Bentall operation, respectively. The aortic annulus was severely damaged and left ventriculo-aortic discontinuity was found in both cases. We used the freestyle stentless bioprosthesis, which fits well to the destroyed aortic annulus with left ventriculo-aortic discontinuity, because of its flexibility. Postoperative echocardiography revealed excellent hemodynamic results in both cases. Although the long-term results obtained with the freestyle stentless bioprosthesis, such as resistance to bacterial infection, have not been reported, this prosthesis appears to be very useful for treatment of prosthetic valve endocarditis. We expect that this prosthesis might be a option for PVE as an alternative to a homograft.

Adult↗

PubMed2000

Use of A heparin-coated circuit for extracorporeal circulation with selective cerebral perfusion.

The use of selective cerebral perfusion with a heparin-coated extracorporeal circuit has not been reported. We developed a unique extracorporeal circulation system that can be used for selective cerebral perfusion based on an existing heparin-coated circuit with a centrifugal pump for general open-heart surgery and a heparin-coated oxygenator without venous drainage by gravity. Between July 1994 and December 1999, this system was used for 12 patients undergoing surgery for true aortic arch aneurysm. The dose of heparin used was reduced to maintain minimum activated clotting time above 300 sec during extracorporeal circulation. One patient suffered a stroke, and one patient had transient postoperative neurologic deficit. One patient died suddenly of ventricular arrhythmia on the 11th postoperative day. The circuit remained thrombus-free. Selective cerebral perfusion with a heparin-coated bypass circuit was safe and very easy to perform after a simple modification of a standard circuit for open-heart surgery.

Aged↗

PubMed1999

Acute acalculous cholecystitis complicated by penetration into the liver after coronary artery bypass grafting.

BACKGROUND: Perforation or penetration due to acute acalculous cholecystitis is a rare complication after open-heart surgery. The mortality rate of this disease is high. METHODS: A 71-year-old woman complained of a sudden onset of right upper abdominal pain with development of peritoneal signs at 21 days after coronary artery bypass grafting. Abdominal ultrasonography and laboratory examination performed at 1 day earlier had revealed no abnormalities. Neither anticoagulants nor antiplatelet agents were administered following the bypass operation. An exploratory laparotomy was performed to locate a presumed embolization to the superior mesenteric artery. RESULTS: Laparotomy revealed acute acalculous cholecystitis complicated by penetration into the liver, causing a subserosal hematoma. The hematoma had ruptured into the abdominal cavity. A cholecystectomy was performed. The gallbladder wall which was in contact with the liver was necrotic. Most of the gallbladder mucosa was necrotic. Microscopical examination revealed atherosclerosis of the cystic artery which was partially obstructed by thrombus. CONCLUSIONS: Given the atherosclerotic condition of the cystic artery, hypotension during the bypass in combination with postoperative total parenteral nutrition and hypovolemia may have induced the cystic artery thrombosis. Surgeons who manage patients with cardiovascular disease should be aware of this potentially lethal development.

Acute Disease↗

PubMed1999

Stuck valve leaflet detected by intraoperative transesophageal echocardiography.

We encountered a rare complication of mitral valve replacement with the CarboMedics prosthesis: a "stuck" leaflet detected by transesophageal echocardiography even though weaning from cardiopulmonary bypass had been uneventful. The patient was immediately managed without significant problems. We emphasize the importance of performing routine intraoperative transesophageal echocardiography in valve replacement as well as in valve repair, from the initial phase of operation.

Echocardiography, Transesophageal↗

PubMed1999

Coagulofibrinolysis during heparin-coated cardiopulmonary bypass with reduced heparinization.

BACKGROUND: We examined the safety of reduced systemic heparinization during heparin-coated cardiopulmonary bypass by measuring coagulofibrinolitic indices, including fibrinopeptide A, which directly reflects fibrinogenesis. METHODS: Twenty-four patients who had elective cardiac operations were perfused using a circuit coated with covalently bonded heparin. Twelve patients received 300 U/kg of heparin and the remaining 12 patients received 150 U/kg. Blood was obtained for the measurement of thrombin-antithrombin III complexes, fibrinopeptide A, plasmin-alpha 2 plasmin inhibitor complexes, and D-dimer preoperatively; after heparin administration; 10, 60, and 90 minutes after the start of bypass; after protamine administration; and 1, 3, 6, 12, and 24 hours after the end of bypass. RESULTS: Preoperative, intraoperative, and postoperative variables including postoperative bleeding were not significantly different between the two groups. Further, there were no complications in either group. No significant differences between the two groups were noted for any hematologic index at any time point. CONCLUSIONS: Reduced systemic heparinization combined with a heparin-coated cardiopulmonary bypass circuit is biochemically and clinically safe but does not reduce postoperative bleeding.

Adult↗

PubMed1999

Assessment of transmural coronary blood flow with intraoperative transesophageal color Doppler echocardiography during coronary revascularization.

Intraoperative color Doppler transesophageal echocardiography with a 4- to 7-MHz transducer was performed on 28 consecutive patients who underwent coronary artery bypass grafting to image and evaluate the transmural coronary blood flow before and after cardiopulmonary bypass. The transmural coronary flow was visualized in 26 (92.8%) of 28 patients in the inferior wall and in 13 (46.4%) of 28 patients in the lateral wall. The peak diastolic flow velocity of the transmural coronary artery in the inferior and lateral wall was significantly increased after coronary revascularization in patients with a successful bypass graft to the right coronary artery (from 34.0 +/- 19.7 to 64.9 +/- 30.9 cm/s, P <.001, n = 10) and to the left circumflex coronary artery (from 35.1 +/- 18.6 to 62.1 +/- 21.1 cm/s, P <.001, n = 10). No significant changes were observed in patients with no bypass graft to the right or left circumflex coronary artery. Coronary blood flow can be mapped and the velocity measured with Doppler transesophageal echocardiography with a high-frequency (4- to 7-MHz) transducer. Assessment of the transmural coronary flow may provide valuable information and aid in decision making during surgical revascularization.

Adult↗

PubMed1999

Use of heparin-coated cardiopulmonary bypass circuit with low-dose heparin reduces postoperative bleeding.

Postoperative bleeding was examined in patients undergoing cardiopulmonary bypass with a heparin-coated circuit and low-dose heparin. Out of 150 patients who underwent cardiopulmonary bypass for longer than 90 minutes, 74 received a standard dose (300 IU/kg) of heparin with an uncoated circuit (group C) and 76 received a low-dose (150 IU/kg) of heparin with a heparin-coated circuit (group H). The coagulation and fibrinolytic systems were investigated in 24 patients. Re-opening of the chest due to bleeding was performed in 5 patients in group C (7%), but none of the patients in group H (p=0. 03). The median of blood loss in the first 12 hours after surgery was 292 ml in group C, and 216 ml in group H (p=0.006). There were no significant differences in the peak thrombin-antithrombin complex concentration between the two groups. The plasmin-alpha 2 plasmin inhibitor complex concentrations after protamine administration were 1.9 ng/ml (median) in group C and 1.1 ng/ml in group H (p=0.002). The use of heparin-coated cardiopulmonary bypass circuits with low-dose heparin suppressed the activation of fibrinolysis. This may explain the reduction in postoperative bleeding.

Adult↗

PubMed1999

Use of a retractor designed to harvest an internal thoracic artery graft during cardiac surgery for patients with a unilateral lung.

Adequate exposure of the heart is required for safe cardiac surgery. We performed open heart surgery for 2 patients with a unilateral lung. In one patient, coronary artery bypass grafting was performed 13 years after left pneumonectomy for lung cancer. Mitral valve replacement was performed in the other patient whose left lung was entirely collapsed due to tuberculosis. The heart was markedly deviated to the left in both patients. A retractor designed to harvest the internal thoracic artery was very useful to obtain a good operative view of the heart. The operations were uncomplicated, and postoperative recovery was uneventful in both patients.

Aged↗

PubMed1999

Cardiac surgery in patients with dialysis-dependent renal disease.

This study was designed to evaluate the operative outcome of dialysis patients undergoing cardiac surgery. A retrospective review was performed of 28 consecutive patients with end-stage renal disease dependent on maintenance hemodialysis (n = 26) or peritoneal dialysis (n = 2) who underwent cardiopulmonary bypass (CPB). The operations included isolated coronary artery bypass grafting (CABG) (n = 21), aortic valve replacement (n = 4) and CABG plus aortic valve replacement (n = 3). Seven operations were emergent or urgent. In 23 patients, a heparin-coated (HC) circuit with reduced systemic heparinization was used for CPB. The hospital mortality was 7.1%. Complications occurred in 13 patients (46%). Although thoracotomy for bleeding was required in 3 patients, only 1 had undergone CPB with an HC circuit. There were 7 late deaths. All survivors showed improvement in symptoms and overall functional status. The actuarial survival rates were 78% and 58% at 1 and 4 years, respectively. In the 10 patients with diabetes mellitus, the 4-year survival rate was 50%. In the patients who underwent non-elective surgery, the survival rate was 29%. Cardiac surgery can be performed with increased but acceptable mortality in dialysis patients. Good symptomatic relief can be expected. Surgery should be performed before the general condition deteriorates.

Actuarial Analysis↗

PubMed1999

Heparin-coated circuits prevent renal dysfunction after open heart surgery.

UNLABELLED: We examined whether heparin-coated (HC) circuits can improve the operative results in patients with chronic renal insufficiency. SUBJECTS AND METHODS: Elective cardiac surgery was performed in 24 patients with a serum creatinine (Cr) level of at least 1.5 mg/dl. Uncoated circuits were used in 12 patients, and HC circuits were used in 12 patients. The results of surgery were compared between the two groups. RESULTS: The mean preoperative Cr concentration was significantly higher in the HC group (2.3 vs 1.8 mg/dl). The heparin doses, protamine dose, and activated clotting times were significantly lower in the HC group. The mean blood loss was also less, although this difference was not significant. The postoperative increase in the Cr level was small in the HC group (2.3-->2.5 mg/dl) compared to that in the noncoated group (1.8-->2.3 mg/dl). Postoperative dialysis was not required in the 5 patients in the HC group with a preoperative Cr clearance less than 20 ml/min. CONCLUSION: HC circuits and low-dose heparin can be used to maintain renal function after cardiopulmonary bypass, even in patients with severe kidney disease.

Aged↗

PubMed1998

Effect of neurotropin on the binding of high molecular weight kininogen and Hageman factor to human umbilical vein endothelial cells and the autoactivation of bound Hageman factor.

Bradykinin is generated by activation of the plasma kallikrein-kinin (K-K) cascade and contributes to the symptoms of allergic reactions and the perception of pain. Neurotropin is a biological material obtained from inflamed rabbit skin inoculated with vaccinia virus, which is widely used clinically in Japan as an effective agent for these disorders. Factor XII (FXII) and high molecular weight kininogen (HK), two critical constituents of the plasma K-K cascade, bind to endothelial cells, and bound FXII is autoactivated in the presence of zinc ions. We have investigated the effects of Neurotropin on the interactions of FXII and HK with endothelial cells. Neurotropin inhibited the binding of both proteins to cultured human umbilical vein endothelial cells (HUVEC) and inhibited autoactivation of FXII upon HUVEC in a concentration-dependent manner. These data suggest that the ameliorating effects of Neurotropin in allergic disorders and pain syndromes may be related to this ability to inhibit activation of the K-K cascade and, consequently, the formation of bradykinin.

Binding, Competitive↗

PubMed1998

[Blunt traumatic rupture of right ventricle and pericardium].

A 60-year-old man was transferred to our hospital for blunt trauma of the chest suffered in a traffic accident. He had a weak pulse, and cardiopulmonary resuscitation was continued in the ambulance. Chest roentgenography revealed left hemothorax, and echocardiography revealed pericardial bleeding. He was immediately transported to the operating room, because of severe hypotension due to massive bleeding from the chest drainage tube. Median sternotomy was performed under stand-by cardiopulmonary bypass. There was projectile bleeding from the anterior wall of the right ventricle. The site of rupture was sutured with felt strip. A tear in the pericardium was also present at the apex. Postoperative recovery was uneventful. Fulda et al. reported that the incidence of combined pericadial and cardiac chamber rupture was 8% for those patients suffering blunt chest trauma, and that the rate of survival was less than 15% for blunt heart rupture. We have reported here successful repair of combined rupture of the right ventricle and pericardium.

Accidents, Traffic↗

PubMed1998

[Primary cardiac synovial sarcoma--a case report].

We report a case of cardiac synovial sarcoma, a very rare primary tumor of the heart. The patient was a 29-year-old man with chief complaint of dyspnea. On echocardiography, a tumor 42 mm in diameter occupying the most space of the left atrium was found. The tumor was obstructed the opening of the mitral valve. He was diagnosed with heart failure due to disturbance of the pulmonary venous return and hemodynamic mitral valve stenosis, and underwent surgery. The tumor was a 5-cm sphere originating in the left atrial posterior wall, and was covered with a sheath and solid. The atrial posterior wall was covered with a peel that appeared to be tumor tissue, and this tissue expanded toward the openings of the pulmonary veins bilaterally and the posterior cusp of the mitral valve. The tumor was resected together with the posterior wall. On pathologic examination, the tumor was diagnosed as a synovial sarcoma. Since no other primary focus was found, this tumor was judged to be a primary sarcoma of the heart. The patient was discharged with elimination of symptoms. The sarcoma recurred after 4 months, and the patient underwent a second operation. The recurrent tumor began from the site of resection of the previous operation and expanded up to the inferior pulmonary veins bilaterally. A wide area of the left atrial wall including the tumor was resected, and he was discharged again. The sarcoma recurred again, and he died of progression of heart failure and aggravation of general conditions after 8 months from the first operation.

Adult↗

PubMed1998

Aortocoronary saphenous vein graft aneurysm in redo coronary artery bypass grafting: report of a case.

We report herein the case of an 80-year-old woman who underwent successful redo coronary artery bypass grafting (CABG) for a saphenous vein graft aneurysm found 10 years after her initial operation. On presentation, coronary angiography (CAG) revealed aneurysmal dilatation of the saphenous vein graft and severe stenosis of the left main trunk (LMT). A percutaneous transluminal coronary angioplasty (PTCA) of the LMT lesion was performed; however, a CAG after the PTCA revealed restenosis and the patient developed anginal chest pain at rest. Thus, repeat CABG was urgently carried out, which was followed by a good outcome. Histological examination of the aneurysmal dilatation showed a true aneurysm. Only 15 other cases of redo CABG for this indication have been reported, the features of which are also discussed.

Aged↗