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T Sueda

Publications and source records attributed to T Sueda.

At least 37 records · Page 2Linked to original sources
PubMed2001

Pulmonary vein orifice isolation for eliminating paroxysmal atrial fibrillation after ICD implantation.

We treated a patient with dilated cardiomyopathy (DCM) and sustained ventricular tachycardia by an implantable cardioverter defibrillator (ICD). He then suffered from inappropriate ICD shocks triggered by paroxysmal atrial fibrillation (AF). We successfully performed pulmonary vein orifice isolation to eliminate paroxysmal AF. The pulmonary vein orifice isolation was a simple and useful procedure for eliminating paroxysmal AF in patient with decreased left ventricular (LV) function after ICD implantation.

Adult↗
PubMed2001

[Serum cytokine levels response to cardiac surgery with cardiopulmonary bypass].

The response of tumor necrosis factor alpha (TNF alpha), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), interleukin-1 receptor antagonist (IL-1ra), macrophage colony stimulating factor (MCSF), white blood cell (WBC), platelet (Plt), lactic acid (LAC) to cardiopulmnary bypass (CPB) were studied until 48 hours after aortic declamping in 11 patients who underwent elective CABG (n = 4), mitral valve plasty or replacement with modified maze procedure (n = 5), and both procedures (n = 2). The highest levels of the cytokines IL-6, IL-8, IL-10, and IL-1ra were observed after the removal of the cross clamp. These cytokines just after the aortic declamping are likely to be occurred not only by an interaction of the blood components with the artificial surfaces, but also by ischemia-reperfusion injury upon discontinuation of the aortic clamping. MCSF increased gradually in the late post-CPB phase and reached a peak at 48 hr after aortic declamping. MCSF may play an important role in regulating hematopoiesis on the postoperative days 1 and 2 in patients. In conclusion, the therapy based on the kinetics of these cytokines would be useful for patients undergoing CPB.

Aged↗
PubMed2001

[Bacteria isolated from surgical infections and their susceptibilities to antimicrobial agents. Special references to bacteria isolated between April 1998 and March 1999].

The annual multicenter studies on isolated bacteria from infections in general surgery and their antimicrobial susceptibility have been conducted in Japan since July 1982. This paper describes the results obtained in fiscal 1998 (from April 1998 to March 1999). The number of cases investigated as objectives was 225 for one year. A total of 429 strains (121 strains from primary infections and 308 strains from postoperative infections) were isolated from 183 cases (81.3% of total cases). In primary infections, the isolation rates of anaerobes and Escherichia coli were higher than in postoperative infections, while in postoperative infections, those of Gram-positive aerobes and Pseudomonas aeruginosa were higher than in primary infections. On the whole, among Gram-positive aerobes, the isolation rate of Enterococcus faecalis was the highest, followed by Staphylococcus aureus with high frequency in isolation from postoperative infections. Among Gram-positive anaerobes, Peptostreptococcus spp. and Streptococcus spp. were predominantly isolated. Among Gram-negative aerobes, E. coli, P. aeruginosa, Klebsiella pneumoniae and Enterobacter cloacae were frequently isolated. Among Gram-negative anaerobes, Bacteroides fragilis group was the majority of isolates. In primary infections, the percentage of Gram-negative aerobes has gradually increased since fiscal 1995 or 1996 with these years as the turning point, while those of Gram-positive and Gram-negative anaerobes have gradually declined. In postoperative infections, the percentage of Gram-negative anaerobes has increased continuously since the mid-1980s. The percentage of MRSA among S. aureus rose to 89.7%, which was the highest level since the beginning of this study. The susceptibilities of B. fragilis, which did not show apparent changes, were recognized to have decreased against cephems in fiscal 1998. Among other bacteria in B. fragilis group, development of resistance to cephems has continued on a long-term basis since the mid-1980s. E. coli and K. pneuminiae have obviously not changed in susceptibilities, however, the susceptibilities of isolated strains in fiscal 1998 against high-generation cephems, oxacephems and monobactams have declined. We found neither vancomycin-resistant nor teicoplanin-resistant strains of S. aureus and Enterococcus spp.

Anti-Bacterial Agents↗
PubMed2000

Evaluation of motor- and sensory-evoked potentials for spinal cord monitoring during thoracoabdominal aortic aneurysm surgery.

OBJECTIVE: To assess the utility of spinal cord monitorings for prediction of spinal cord ischemia, we investigated the role of both motor evoked potentials and sensory evoked potentials during thoracoabdominal aortic aneurysm surgeries. METHODS: We monitored two kinds of sensory evoked potentials; descending evoked spinal cord potentials from the lumbar enlargement after cervical spinal cord stimulation and segmental evoked spinal cord potentials at the lumbar enlargement elicited by peroneal nerve stimulation, and motor evoked potentials from the lumbar enlargement elicited by direct subcranial stimulation in 9 thoracoabdomonal aortic aneurysm surgeries. RESULTS: Postoperative paraplegia occurred in one case in which the patients died during the perioperative period. One case showed transient paraparesis, but recovered following rehabilitatation. These cases showed a decrease in the amplitude of descending evoked spinal cord potentials and motor evoked potentials. CONCLUSION: The recovery of the amplitude of the motor evoked potentials and the descending evoked spinal cord potentials after declamping correlated with the neurologic outcome.

Aged↗
PubMed2000

Central retinal artery color Doppler monitoring versus transcranial Doppler monitoring in cardiac surgery.

We hypothesized that the central retinal artery color Doppler (CRAD) technique can be used as an alternative monitoring method to the conventional transcranial Doppler (TCD) technique which does not consistently provide good signals during cardiopulmonary bypass. This is the first study to compare CRAD with TCD during cardiac surgery. Twenty patients without stroke were examined at the seven preset stages of the two procedures. The maximum flow velocity (Vmax) of the right central retinal artery was measured with a 7.5-MHz Doppler system. The Vmax of the right middle cerebral artery was measured with a TCD system. To estimate the relationship between Vmax and maximum blood pressure (BPmax), CRAD-Vmax (6.6 +/- 2.2 cm/s), TCD-Vmax (44.0 +/-14.8 cm/s), and BPmax (114 +/- 28.5 mmHg) obtained at the initial stage were normalized. The Vmax values of CRAD were successfully obtained, at each of the seven study stages, in all 20 patients. The Vmax values of TCD were obtained at 125 points, and 15 missing values were seen during the stages of cardiopulmonary bypass. CRAD-Vmax was correlated to TCD-Vmax (r = 0.775, P < 0.0001). The normalized values of both TCD- and CRAD-Vmax were correlated to the normalized BPmax (r = 0.766, P < 0.0001) (r = 0.787, P < 0.0001). The accuracy of CRAD was confirmed by the significant correlation with TCD.

Adolescent↗
PubMed2000

Selective intercostal arterial perfusion during thoracoabdominal aortic aneurysm surgery.

BACKGROUND: This clinical study evaluated changes in motor evoked potentials (MEP) elicited by direct cerebral cortical stimulation and evoked spinal cord potentials (ESCPs) elicited by direct spinal cord stimulation during selective intercostal arterial perfusion for thoracoabdominal aortic aneurysm (TAAA) repair. We also determined the efficacy of this perfusion method for prevention of paraplegia. METHODS: Two kinds of ESCPs and MEPs were monitored during the prosthetic replacement step for TAAA surgeries. We performed selective intercostal arterial perfusion from the T7 intercostal artery to the L1 intercostal artery through a small piece of Dacron graft while monitoring spinal cord potentials in five cases of TAAA. RESULTS: The MEP amplitude decreased after clamping the aorta but quickly recovered after selective perfusion of intercostal arteries. Other spinal cord potentials did not change during the reconstruction of intercostal arteries. Postoperative paraplegia or parapalesis did not occur in any of the patients. CONCLUSIONS: Monitoring of MEPs during selective intercostal arterial perfusion was a useful adjunct to prevent postoperative paraplegia in TAAA surgery.

Adult↗
PubMed2000

Cardioprotective effects of FK409, a nitric oxide donor, after isolated rat heart preservation for 16 hours.

BACKGROUND: We examined the cardioprotective effects of FK409, a nitric oxide donor, after isolated rat heart preservation. METHODS: FK409 was administered to the hearts in pretreatment (FK409-1 group), during ischemia (FK409-2), or during reperfusion (FK409-3). The combined nitrate and nitrite level, coronary flow, cardiac function, coronary vasodilatory response, creatine kinase (CK), and myocardial water content were evaluated after the hearts had been preserved in University of Wisconsin solution at 0 degrees C for 16 hours. RESULTS: The release of nitrate and nitrite increased in reperfusion between the 20-to-40-second measurement and the measurement at 40 minutes, and the recovery of cardiac function was significantly improved in the FK409 groups. The coronary vasodilatory response to acetylcholine chloride was enhanced in the FK409-1 and FK409-2 groups. CK release decreased in FK409 groups after 15 minutes in reperfusion. CONCLUSIONS: This study suggests that FK409 has the best protective effect on cardiac function and coronary endothelial function when it is administered in the ischemic period, a less protective effect when administered during pretreatment, and the least protective effect when FK409 is given during reperfusion after heart preservation for 16 hours.

Acetylcholine↗
PubMed2000

Endovascular stent-grafting through the aortic arch: an alternative approach for distal arch aortic aneurysm.

BACKGROUND: Endovascular stent-grafting is an innovative procedure; we have developed a novel approach to treat distal arch aortic aneurysm through a small incision in the aortic arch. METHODS: Eight patients with thoracic aortic aneurysms were treated with an endovascular stent-graft that was introduced into the thoracic aorta through a small incision in the aortic arch. Of these patients, 7 had distal arch aortic aneurysms, and 1 had chronic aortic dissection of Stanford type B. Four of these patients had received concomitant coronary artery bypass grafting, and 1 patient had undergone tricuspid valvular annuloplasty. The stent-graft was introduced into the distal arch aorta and descending aorta through a small incision in the aortic arch, under selective cerebral perfusion and hypothermic circulatory arrest. RESULTS: The selective cerebral perfusion time ranged from 52 to 86 minutes (mean, 68 minutes) and the operating time from 289 to 422 minutes (mean, 318 minutes). There was no endoluminal leakage into the aneurysm. Seven patients survived and were discharged, but 1 patient suffered a cerebral infarction and died during the follow-up period. CONCLUSIONS: Placing an endovascular stent-graft through the aortic arch is an acceptable alternative treatment for distal arch aortic aneurysms.

Aged↗
PubMed2000

Type 2 angiotensin II receptor is downregulated in cardiomyocytes of patients with heart failure.

BACKGROUND: The human heart expresses type 2 angiotensin (AT(2)) receptor, but the function is poorly defined. METHODS: In the present study, we investigated (1) the cellular localization of the AT(2) receptor and (2) the relationship between the AT(2) receptor protein expression and the cardiac function of patients with ischemic heart disease. The receptor localization was assessed by immunohistochemistry and the protein expression was quantified by Western blotting in atrial tissues freshly obtained from 22 patients undergoing coronary artery bypass graft surgery (63.0+/-11.0 years old; male ratio, 85%). Prior to the surgery, blood was drawn for determination of atrial-natriuretic hormone level and the left ventricular function was assessed by ultrasound cardiography. RESULTS: The results of immunohistochemistry showed that the AT(2) receptor was localized to cardiomyocytes and was not present in fibroblasts, vascular smooth muscles, or vascular endothelium. Atrial tissues showed various degrees of structural remodeling, but the localization of the AT(2) receptor was not altered in any tissue sections. The amount of the AT(2) receptor was negatively correlated with end-diastolic left ventricular diastolic dimension (r=-0.56, P<0.01), calculated left ventricular mass index (r=-0.51, P<0.02) and the plasma atrial natriuretic peptide (ANP) concentration (r=-0. 62, P<0.01) and positively correlated with left ventricular ejection fraction (r=0.48, P<0.05). CONCLUSIONS: (1) The AT(2) receptor is localized to cardiomyocytes independently of the cardiac function. (2) Left ventricular dysfunction is associated with decreased expression of myocardial AT(2) receptor protein.

Adult↗
PubMed2000

Expression and activity of thrombomodulin in human gingival epithelium: in vivo and in vitro studies.

Epidermal keratinocytes thrombomodulin (TM) has been shown to regulate thrombin at sites of cutaneous injury in addition to a role for epidermal differentiation. TM, a major anticoagulant proteoglycan of the endothelial cell membrane, is a thrombin receptor that acts as a co-factor for protein C activation. Thrombin has pro-inflammatory effects for periodontitis. However, little is known about TM in gingival tissue with periodontitis. We used immunohistochemistry to examine expression of TM in gingival epithelium from patients with periodontitis. In vitro, we observed TM expression at varying Ca2+ concentrations by confocal laser scanning microscopy, examined the expression of TM mRNA and tested TM co-factor activity. Furthermore, we measured TM concentration in gingival crevicular fluid (GCF) from 11 severe adult cases of periodontitis using enzyme-linked immunosorbent assay. Immunoreactive TM was present in gingival epithelium and junctional epithelium, and was reduced in inflamed gingival epithelium compared to healthy gingival epithelium. Ultrastructurally, TM, including microvilli, was observed on the cell membrane. TM localization in cells cultured in 0.09 mM Ca2+ differed from that in cells exposed to 1.2 mM Ca2+. Northern analysis demonstrated TM mRNA in gingival keratinocytes more than in human umbilical vein endothelial cells (HUVEC). Gingival keratinocytes also facilitated protein C activation by thrombin, although less strongly than HUVEC. TM in GCF at sites with bleeding on probing in patients was significantly elevated (p < 0.001, Student's t-test). TM in gingival epithelium may regulate thrombin activity at sites of coagulation and inflammation with periodontal disease, although inflammation may impair this regulation of thrombin.

Adult↗
PubMed2000

Cerebral tissue oxygen saturation during percutaneous cardiopulmonary support in a canine model of respiratory failure.

Percutaneous cardiopulmonary support (PCPS) has come to be applied for cardiopulmonary resuscitation and in the management of severe respiratory failure as well as severe heart failure. We investigated cerebral tissue oxygen saturation during PCPS in a canine model of respiratory failure using near-infrared spectroscopy. Animals were mechanically ventilated with 10% oxygen to make a respiratory failure model. Perfusion with PCPS was performed via the left femoral artery and switched to that via the right axillary artery. Cerebral tissue oxygen saturation was 54.2 +/- 3.4% during PCPS via the femoral artery and was 82.3 +/- 4.6% during PCPS via the axillary artery (p = 0.001). Hepatic tissue oxygen saturation was not significantly different. LV dP/dt max increased significantly after switching to the axillary blood supply (p = 0.001). Conventional PCPS may not have the capability of supporting cerebral circulation under severe respiratory failure without organic heart disease.

Analysis of Variance↗
PubMed2000

Eccentric roller type total artificial heart creating interatrial shunt.

Creating an interatrial shunt to achieve left-right flow balance and modification of the blood chambers to improve the basic performance of the device were performed in developing an eccentric roller type total artificial heart (ERTAH). Smaller blood chambers reduce friction loss and increase durability and energy efficiency. We changed the left blood chamber volume of 60 ml to 40 ml and the right blood chamber volume of 53 ml to 35 ml compared with previous types. Designs of inlet and outlet ports were modified to prevent backflow. In the mock circulatory system, redesigning the blood chambers resulted in a 20% increase in energy efficiency, about a two-fold increase of cardiac output and improved durability compared to the previous type. In an animal experiment, the ERTAH operated at a driving rate of 160 rpm with a left flow rate of 6.0 L/min and a right flow rate of 5.4 L/min. Interatrial shunt flow rate was 250-400 ml/min.

Animals↗
PubMed2000

Low power laser protects human erythrocytes In an In vitro model of artificial heart-lung machines.

The protective effect of the low power helium-neon (He-Ne) laser against the damage of human erythrocytes in whole blood was examined in a perfusion model using an artificial heart-lung machine. Preserved human whole blood was diluted and perfused in 2 closed circuits with a double roller pump. The laser irradiated one of the circuits (laser group), and none the other (control group). In the laser group, erythrocyte deformability and erythrocyte adenosine triphosphate (ATP) levels were significantly higher, and free hemoglobin levels were significantly lower than those in the control group. Subsequent morphological findings by means of scanning electron microscope were consistent with these results. Low power He-Ne laser protected human erythrocytes in the preserved diluted whole blood from the damage caused by experimental artificial heart-lung machines. The clinical application of low power laser treatment for extracorporeal circulation is suggested.

Adenosine Triphosphate↗
PubMed2000

Aortic arch branches are no longer a blind zone for transesophageal echocardiography: a new eye for aortic surgeons.

OBJECTIVES: Branch arteries of the aortic arch have been a blind zone for transesophageal echocardiography. Information regarding blood flow, which is important in both planned and emergency operations on the aorta, has therefore been limited. We have established a technique for visualizing these arteries in nearly all cases. METHODS: In 25 consecutive patients requiring either planned or emergency operations on the aorta, the branch arteries were visualized whenever cerebral malperfusion was suspected. Lateral flexion of the probe tip was used when the trachea interfered with visualization of the arteries. RESULTS: The left subclavian, left and right common carotid, right subclavian, innominate, and left and right vertebral arteries were visualized in 96% (24/25), 92% (23/25), 96% (24/25), 100% (25/25), 84% (21/25), 92% (22/24), and 88% (21/24), respectively. The origin of the innominate artery was visualized in 36% (9/25). In some cases, dissection extended into branch arteries during surgery or during conservative therapy. When the subclavian artery was clamped, retrograde flow was detected in the vertebral artery (steal flow). The cannula for selective cerebral perfusion occasionally was entered into the right common carotid or subclavian artery and obstructed the other branch with a balloon. CONCLUSIONS: The branch arteries of the aortic arch, including the vertebral artery, are no longer a blind zone for transesophageal echocardiography. The information obtained with our new transesophageal echocardiography technique is helpful for diagnosis, monitoring, and decision making during aortic surgery and in critical care medicine. Visualizing these vessels is worth the effort.

Adult↗
PubMed2000

Echocardiography-assisted surgery in transaortic endovascular stent grafting: role of transesophageal echocardiography.

OBJECTIVE: Transesophageal echocardiography was applied to visualizing endovascular procedures during transaortic stent grafting for aneurysm and dissection at the distal arch, and the use of transesophageal echocardiography was evaluated. METHODS: The 16 consecutive patients (13 with aneurysms and 3 with dissections) were examined. Transesophageal echocardiography was used for (1) determining graft size, (2) guiding placement of the catheter in the descending aorta at an appropriate position without intimal damage, (3) guiding graft tailoring with a balloon catheter, and (4) examining the results after the procedures. RESULTS: Visualization was disturbed in one patient who had undergone a previous operation. The graft size was appropriate, except in one patient as a result of underestimation. Transesophageal echocardiography was helpful for navigating the graft placement and tailoring without intimal damage. We tried to keep a distance from the diaphragm of 9 cm and an attachment portion of 4 cm. In one patient the graft was placed too distally (7 cm from the diaphragm) to cover the thick atheromatous plaque with the graft. The patient had paraplegia. Transesophageal echocardiographic assessment of endoleak and thromboexclusion was identical to that of postoperative computed tomography or angiography, with a sensitivity of 100% (1/1) and a specificity of 100% (13/13). Leakage at the proximal suture and graft kinking were found in 3 patients. Successful thromboexclusion by transesophageal echocardiographic assessment (13 patients) was predictive of subsequent regression of aneurysm and dissection in the midterm follow-up period: there was complete and partial regression in 5 and 8 patients, respectively. CONCLUSION: Transesophageal echocardiography enables echocardiography-assisted operations with secure step-by-step endoluminal procedures and immediate intraoperative assessment, which is predictive of the postoperative results.

Adult↗
PubMed2000

Cardiac tumor biopsy under the guidance of intracardiac echocardiography.

Transthoracic echocardiography or transesophageal echocardiography is sometimes useful in intracardiac tumor biopsy. Intracardiac echocardiography was used as an alternative to either of these for performing a biopsy of a right cardiac tumor in a 79-year-old woman. The procedure was well tolerated and no complications occurred. Histopathological findings and immunohistological staining were compatible with the diagnosis of neurogenic sarcoma.

Aged↗
PubMed2000

Newly designed eccentric roller type total artificial heart.

We have produced an eccentric roller type total artificial heart (ERTAH). As the first step in the development of this ERTAH, we conducted simulations such as a numerical simulation, a mock test, and an acute animal experiment using DeBakey roller pumps to analyze the left-right balance during its operation. The next step was redesigning the blood chambers to improve energy efficiency and implanting the ERTAH with an interatrial shunt into an animal for evaluation of the in vivo performance of the device. In the simulations, shunt flow through the bronchial arteries was approximately 500-600 ml/min, and the interatrial resistance was varied from 2.9-7.7 mmHg.min/liter. Redesigning the blood chambers resulted in the mock test in a 20% increase in energy efficiency, about a two-fold increase in cardiac output and improved durability compared to the previous type in the mock test. In the animal experiment the ERTAH operated with a left flow rate of 6.0 liters/min and a right flow rate of 5.4 liters/min. The interatrial shunt flow rate was 250-400 ml/min. Creating an interatrial shunt is a useful method for balancing the blood flow between the left and right heart of the ERTAH. A decrease in friction resistance and the prevention of backward flow resulted in an increase in energy efficiency, cardiac output, and improved durability, in spite of downsizing the blood chambers.

Animals↗