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T Isomura

Publications and source records attributed to T Isomura.

At least 19 recordsLinked to original sources
PubMed2004

[Acute pulmonary embolism after cesarean section; report of a case].

We present a case of acute pulmonary embolism (APE) after cesarean section. A cesarean section was performed on a 27-year old woman with normal course. However, one day after operation, she suddenly developed syncope and dyspnea. Soon after the symptom, she developed hypotension 60 mmHg. As a result of various examinations, her illness was diagnosed as APE with right ventricular dysfunction after cesarean section. She was consulted to our hospital for treatment. Soon after her arrival, we treated her for both APE and cardiogenic shock. The combined with antithrombotic therapy using heparin sodium, was successfully treated the patient from cardiogenic shock due to APE with right ventricular dysfunction after cesarean section.

Acute Disease↗
PubMed2001

Left ventricle restoration in patients with non-ischemic dilated cardiomyopathy: risk factors and predictors of outcome and change of mid-term ventricular function.

OBJECTIVE: The partial left ventriculectomy (PLV) for end-stage dilated cardiomyopathy (DCM) which worked in some patients has been reported, although the hospital mortality is high. To reduce hospital mortality, we selected operative procedures of left ventricular (LV) restoration to improve the operative results. We analyzed the risk factors and predictors of outcome, and the mid-term changes of the LV function were determined. PATIENTS AND METHODS: Between December 1996 and September 2000, 74 patients with non-ischemic DCM received LV restoration. The age ranged from 14 to 76 years (mean, 49.0+/-14.0 years), and there were 63 men and 11 women. The etiology of the DCM was idiopathic DCM in 49 patients, and dilated hypertrophic cardiomyopathy in seven patients and others in 18. The preoperative New York Heart Association (NYHA) functional class was 29 in class III and 45 in class IV, in which 32 patients depended on inotropic support. PLV or septal anterior ventricular exclusion (SAVE) was selected depending on the akinetic lesion of the LV based on the intraoperative echo-test. Fifty-six patients received elective operations, and emergency operations were performed in 18 patients. The risk factors and predictors of outcome were analyzed in 74 patients, and in 35 patients who survived more than 1 year after receiving LV restoration, the mid-term cardiac function was examined by cardiac echogram and catheterization. RESULTS: PLV was performed in 62 patients and SAVE in 12 patients. Concomitant mitral surgery was performed in 66 patients (89%) and tricuspid annuloplasty in 42 patients (57%). There were 15 hospital deaths and 13 patients died after discharge from the hospital (cardiac deaths in nine and non-cardiac deaths in four). In the 46 late survivors, the NYHA class was I or II in 42 patients and III in four patients. Selection of the procedure of LV restoration (P<0.01), elective operation (P<0.05), and the preoperative volume of LV (endodiastolic volume index of <180 ml/m(2); P<0.05) were risk factors and predictors influencing hospital and late death. After the operation, the LV function improved significantly and the improvement was maintained at the mid-term period; the LV ejection fraction was 31.8+/-7.9% (P<0.01) at 1 year from 23.0+/-7.3% preoperatively, left ventricular diastolic diameter was 62.8+/-10.9 (P<0.01) from 81.7+/-8.2 mm and the LV endosystolic volume index was 88.5+/-45.8 (P<0.05) from 162.6+/-41.6 ml/m(2). CONCLUSIONS: The operative results improved with the selection of the procedures, with elective operation, and mitral plasty for less cardiac dilatation. The mid-term results of clinical status and LV function showed the effectiveness of the operation.

Adolescent↗
PubMed2001

Left ventriculoplasty for ischemic cardiomyopathy.

OBJECTIVE: In order to treat ischemic cardiomyopathy, which is defined as non-aneurysmal diffuse akinetic left ventricle with chronic heart failure following myocardial infarction, the mid-term effect of the endoventricular circular patch plasty (EVCPP) was studied. MATERIALS AND METHODS: EVCPP has been performed on 54 patients (46 men and eight women with a mean age of 61 years) during 4 years from March 1997 to December 2000. Thirty-two patients (59%) were NYHA class III and 22 patients (41%) were class IV. Nine patients (17%) had mild angina pectoris before the operation but others had no chest pain. Single, double, triple, and left main disease were noted in six, 13, 32, and three patients, respectively. Mean left ventricular ejection fraction was 23.3 +/- 6.3% (6--30%). Coronary artery bypass grafting was concomitantly undergone by 51 patients (94%) and mitral valve reconstruction was done on 19 patients (35%). RESULTS: Two patients (3.7%) needed an intra-aortic balloon pump to wean from cardiopulmonary bypass. Seven patients (12.9%) died in the hospital. Among them, two patients (4.4%) out of 45 patients who underwent elective operation died of stroke and heart failure. Five patients (55.5%) out of nine patients who required emergency operation died of heart failure and multiorgan failure. Late death occurred in six patients (11.1%) due to arrhythmia and heart failure in each of three patients. Out of 41 survivors, 38 patients returned to NYHA class I or II and three patients to class III. Out of 50 patients who underwent left ventricular study before and after operation, ejection fraction increased from 22.8 +/- 6.6 to 36.2 +/- 8.0% and mean left ventricular end-diastolic volume and left ventricular end-systolic volume indices reduced from 152.8 +/- 24.6 to 105.0 +/- 36.5 and from 113.6 +/- 45.7 to 66.4 +/- 28.4 ml/m(2), respectively. Mean pulmonary wedge pressure decreased from 19.1 +/- 8.8 to 14.9 +/- 6.8 mmHg. One-, 2-, and 3-year actuarial survival rates were 87.9, 82.7 and 77.2%, respectively. CONCLUSION: Left ventriculoplasty using EVCPP is effective to exclude the akinetic LV segment, and left ventricular function and clinical status improve in patients with ischemic cardiomyopathy.

Adult↗
PubMed2001

Myocardial inflammatory cell infiltrates in cases of dilated cardiomyopathy as a determinant of outcome following partial left ventriculectomy.

Partial left ventriculectomy (PLV) can be used to treat refractory congestive heart failure caused by dilated cardiomyopathy (DCM). In order to understand the relationship between the underlying myocardial injury and early clinical outcomes after PLV, histopathologic, immunohistochemical and virologic studies of the resected myocardium were performed. The posterolateral left ventricular walls from 27 patients with idiopathic DCM were examined. Cardiomyocyte diameter, degree of myocardial fibrosis, degree of cardiomyocyte degeneration, and degree of inflammatory cell infiltration were compared with mortality rates. Polymerase chain reaction was performed to detect enterovirus genome in the myocardium. Some patients had inflammatory cell infiltrates with focal accumulations of lymphocytes and macrophages, including both cytotoxic/suppressor T-cells and helper/inducer T-cells. The number of inflammatory cells (activated lymphocytes plus macrophages/mm2) was significantly greater in patients who died of cardiac insufficiency after surgery (27.8 +/- 5.7; n = 7) than in the survivors (11.1 +/- 2.5; n = 15). There was no significant difference in the degree of myocardial fibrosis, cardiomyocyte diameter or degree of cardiomyocyte degeneration between the 2 groups. Enterovirus genome was detected in the myocardium of 9 (38%) of 24 patients examined and 5 of these enterovirus-positive hearts had severe inflammatory cell infiltrates (37.9 +/- 2.5/mm2). Early survival in patients undergoing PLV for DCM is significantly affected by the degree of myocardial inflammation, so patients with more severe or ongoing inflammation may have poor clinical outcomes. Chronic myocarditis may play an important role in the etiology and pathophysiology of idiopathic DCM.

Adolescent↗
PubMed2001

Autophagic degeneration as a possible mechanism of myocardial cell death in dilated cardiomyopathy.

In failing hearts, cardiomyocytes degenerate and interstitial fibrosis, which indicates cardiomyocyte loss, becomes more prominent in the myocardium. However, the precise mechanism of cardiomyocyte degeneration that leads to cell death is still unclear, although it is presumed that lysosomal function and autophagy play an important role because lysosomal activity increases under stress such as hypoxia. Myocardium that had been resected during partial left ventriculectomy performed in patients with dilated cardiomyopathy (DCM) was examined. Under light microscopy, some cardiomyocytes had a marked scarcity of myofibrils and had prominent cytoplasmic vacuolization. Atrophic and degenerated cardiomyocytes were often observed adjacent to replacement fibrotic tissue. Immunohistochemistry showed positivity for lysosome-associated membrane protein and a lysosomal catheptic enzyme in vacuoles of various sizes in the cardiomyocytes and these lysosomal markers were markedly increased in atrophic and degenerated cardiomyocytes. Electron microscopy revealed that degenerated cardiomyocytes had many vacuoles containing intracellular organelles, such as mitochondria, and were considered to be autophagic vacuoles. In DCM hearts, autophagy appeared to be associated not only with degradation of damaged intracellular organelles but also with progressive destruction of cardiomyocytes. It is possible that autophagic degeneration is one of the mechanisms of myocardial cell death.

Adult↗
PubMed2001

A double fistula, broncho-cavitary-cutaneous communication caused by cancer invasion.

Pulmonary infection with cavitation causes severe respiratory symptoms if the cavity has a communication with main bronchus, through which fluid flows out into trachea. In this report a young male with lung cancer invading an adjacent pre-existent fungus cavitary lesion is presented. Cancer invasion led to broncho-cavitary communication and caused massive intrabronchial aspiration. Subsequently, the cancer destroyed the thoracic wall, and a cavitary-cutaneous fistula developed which relieved symptoms as if treated with open drainage.

Adult↗
PubMed2001

[Left ventriculoplasty for non-ischemic cardiomyopathy with severe heart failure in 70 patients].

OBJECTIVES: Treatment of cardiac failure due to non-ischemic cardiomyopathy by left ventriculoplasty using partial left ventriculectomy (Batista operation) or septal anterior ventricular exclusion was evaluated. METHODS: Left ventriculoplasty was performed in 70 patients (59 men and 11 women with a mean age of 51 years) from December 1996 to June 2000. Preoperative New York Heart Association (NYHA) functional class was IV in 43 patients including 29 receiving inotropic support, and class III in 27 patients. Nineteen patients required emergency surgery because of on-going shock and 51 patients were operated electively. Combined cardiac procedures were mitral valve reconstruction in 62 patients (45 replacements, 17 repairs), tricuspid annuloplasty in 37, and aortic valve replacement in 4. The initial 24 patients underwent typical Batista operation regardless of myocardial viability. The other 46 patients underwent selective ventriculoplasty to excise or exclude the weakest part according to the findings of the intraoperative echo-guided volume reduction test. RESULTS: The intraaortic balloon pump was used in 12 patients and the left ventricular assist device in 2 patients. Three (5.9%) of the 51 patients who underwent elective operation and 12 (63.2%) of the 19 patients with emergency operation died in the hospital, giving an overall hospital mortality of 21.4% (15/70). Hospital mortality was reduced from 33.3% (8/24) in the initial 24 patients to 15.2% (7/46) in the recent 46 patients with the volume reduction test. Mean ejection fraction increased from 22.2 +/- 6.7% to 29.6 +/- 6.0%. Diastolic dimension decreased from 81.1 +/- 9.5 to 69.8 +/- 19.2 mm. End-diastolic and systolic volume indices decreased from 199.0 +/- 47.9 to 124.1 +/- 34.9 ml/m2 and from 154.0 +/- 41.2 to 89.3 +/- 31.7 ml/m2, respectively, at one postoperative month in the 55 hospital survivors. The mean pulmonary capillary wedge pressure decreased from 25.6 +/- 7.8 to 13.6 +/- 4.5 mmHg. Serum brain natriuretic peptide decreased from 999 +/- 647 preoperatively to 547 +/- 362 pg/ml one month after the operation. Thirteen patients (18.6%) died in the late period mainly due to heart failure. Among the 42 survivors, 37 patients returned to NYHA functional class I-II, and cardiac events were rare after one postoperative year. Actuarial survivals at 3 years in elective and emergency operations were 71.9% and 33.3%, respectively. CONCLUSIONS: Left ventriculoplasty is acceptably safe for elective operation and clinical improvement can be obtained by proper surgical procedures and careful postoperative medical treatment.

Adolescent↗
PubMed2000

Evaluation of viral infection in the myocardium of patients with idiopathic dilated cardiomyopathy.

OBJECTIVES: The aim of this study was to evaluate the viral etiology of idiopathic dilated cardiomyopathy (DCM). BACKGROUND: The demonstration of enteroviral genome in hearts with DCM has reinforced the importance of enteroviruses in the pathogenesis of DCM. However, there is uncertainty about the character and activity of enteroviruses detected in the myocardium. Recently, the association of hepatitis C virus or adenovirus with DCM has been reported. METHODS: Myocardial specimens from 26 patients with idiopathic DCM, which were obtained at partial left ventriculectomy (PLV), were examined virologically. Strand-specific detection of enteroviral RNA was performed to differentiate active viral replication from latent persistence. Polymerase chain reaction was used to detect genomic sequences of hepatitis C virus, adenovirus, cytomegalovirus, influenza viruses, mumps virus, herpes simplex viruses, varicella-zoster virus and Epstein-Barr virus. RESULTS: Plus-strand enteroviral RNA was detected in 9 (35%) of the 26 patients. Minus-strand enteroviral RNA was determined in seven (78%) of these nine plus-strand RNA-positive patients. Sequence analysis revealed that the enteroviruses detected were coxsackie B viruses, such as coxsackievirus B3 and B4. However, genetic material from other viruses was not detected. Six (86%) of seven minus-strand enteroviral RNA-positive patients died of cardiac insufficiency within the first six months after PLV. CONCLUSIONS: Coxsackie B viruses were seen in hearts with idiopathic DCM. Active viral RNA replication appeared to be present in a significant proportion of these cases. Minus-strand coxsackieviral RNA in the myocardium can be a marker for poor clinical outcome after PLV. There was no evidence of persistent infection by other viruses in hearts with DCM.

Adolescent↗
PubMed2000

Preparation of completely 6-O-desulfated heparin and its ability to enhance activity of basic fibroblast growth factor.

Although regioselective removal of 6-O-sulfate groups of heparin has been undertaken by several researchers, complete 6-O-desulfation with little side reaction has not been attained successfully. In this work, a modified method with a certain silylating reagent, N-methyl-N-(trimethylsilyl)trifluoroacetamide, has been established to produce completely 6-O-desulfated heparin with few other chemical changes. The degrees of 6-O-desulfation were estimated by means of chemical disaccharide analyses and/or (13)C NMR spectra. Although the completely 6-O-desulfated heparin lost about 20% of 2-O-sulfate groups, any other chemical changes and depolymerization were not detected. The completely 6-O-desulfated heparin displayed strong inhibition of COS-1 cell adhesion to basic fibroblast growth factor (bFGF)-coated well in a dose-dependent manner, as was clarified by the competitive cell-adhesion assay. Furthermore, the completely 6-O-desulfated heparin was shown to promote in vitro A31 fibroblast proliferation in a dose-dependent manner in the presence of bFGF. These results suggest that signal transduction through bFGF/bFGF receptor in A31 cells occurs in the absence of 6-O-sulfate groups in heparin. The involvement of 6-O-sulfate group(s) of heparin/heparan sulfate in the promotion of bFGF mitogenic activity was reported by several groups. This discrepancy between our results and those of other groups would be due to the differences in molecular size of heparin/heparan sulfate derivatives and/or cell species used for the assay.

Animals↗
PubMed2000

Intraoperative coronary artery imaging with infrared camera in off-pump CABG.

To achieve high quality off-pump coronary artery bypass grafting (CABG), thermal coronary artery imaging using a new generation infrared camera was used and anastomotic status was assessed intraoperatively. In 12 patients who underwent off-pump CABG, 18 grafts (11 internal thoracic, 2 radial, 2 gastroepiploic arteries, and 3 saphenous veins) were evaluated following completion of anastomoses. All grafts were clearly visualized and anastomotic and flow status were observed with local epicardial cooling by CO2 blower in the normothermic heart. Seventeen grafts had no problems and one internal thoracic artery graft showed anastomotic failure that was successfully revised. All grafts were restudied by conventional catheter angiography postoperatively, and all were patent. Intraoperative coronary imaging with a highly sensitive infrared camera is noninvasive and effective for real time evaluation in the operating room. This results in more successful off-pump CABG.

Aged↗
PubMed2000

Coronary artery bypass grafting with gastroepiploic artery composite graft.

BACKGROUND: To achieve better results after coronary artery bypass grafting (CABG), arterial conduits are the first choice in multiple CABG for younger patients. We present here the early results of CABG with gastroepiploic artery (GEA) composite graft with free radial artery (RA) to revascularize right coronary artery or left circumflex artery in addition to internal thoracic artery to left anterior descending artery. METHODS: Between July 1997 and June 1998, 13 patients received CABG with GEA (larger caliber than 2.0 mm) composite graft. We have assessed the early results. RESULTS: There was no postoperative death or major morbidity. Postoperative angiogram was performed in 11 patients and all conduits were patent. Postoperative exercise stress test was done in 13 cases and showed no ischemia. CONCLUSIONS: Multiple CABG with arterial conduit can be performed by this procedure. The free RA functioned from secondary branches derived from proximal GEA. In conclusion, this procedure seems to be safe and effective, and both long-term patency and better quality of life may be expected.

Abdominal Muscles↗
PubMed2000

Partial left ventriculectomy, ventriculoplasty or valvular surgery for idiopathic dilated cardiomyopathy - the role of intra-operative echocardiography.

BACKGROUND: The partial left ventriculectomy (PLV) is known to work in some patients with dilated cardiomyopathy (DCM), although this procedure does not work well in all patients and the operative mortality is higher than the other cardiac surgeries. In addition to PLV, left ventriculoplasty to exclude antero-septal wall or valvular surgery without left ventricle (LV) surgery can be also effective in patients with DCM. To improve the surgical results for dilated cardiomyopathy, we introduced echo-guided volume reduction test and evaluated the surgical procedures and the results on the surgery for DCM. METHODS: Between December 1996 and July 1999, 56 patients with DCM (50 with idiopathic DCM, six with dilated hypertrophic cardiomyopathy) were surgically treated. Under the standard cardiopulmonary bypass, left ventricular motion was determined with color kinesis of echocardiogram and the lesion of akinetic wall was removed or excluded. RESULTS: After the initial PLV in 18 patients (initial group), operative procedures were selected in 21 with PLV, five with LV plasty, or 12 with valve surgery without LV surgery according to the findings of the LV wall motion by intraoperative echogram (select group). There were six hospital deaths and late follow-up deaths within 1 year in initial group, however, the mortality decreased significantly after the selection of the operative procedures; three hospital deaths and two late deaths in the select-group (P<0.05). Significant decrease of left ventricular diameter, the LV ejection fraction and endosystolic volume index were demonstrated after the LV surgery. The survival rate improved significantly after the selection of the operative procedures; 14 months survival rates was 50.0% in initial group and 73.1% in select group (P<0.05). CONCLUSION: Operative mortality decreased and late follow-up results improved after the selection of operative procedures according to the intraoperative volume reduction test.

Adolescent↗
PubMed2000

Nontransplant cardiac surgery for end-stage cardiomyopathy.

OBJECTIVE: To treat end-stage cardiomyopathy, we evaluated endoventricular circular patch plasty, partial left ventriculectomy, and valvular reconstruction alone in our 2-year experience. METHODS: Among 86 patients with heart failure evaluated between December 1996 and February 1999, 33 patients with ischemic cardiomyopathy (25 men and 8 women; mean age 61 +/- 7.8 years; New York Heart Association class 3.5 +/- 0.5) were treated with endoventricular circular patch plasty combined with coronary bypass grafting (84%) and mitral reconstruction (36%). The other 53 patients with nonischemic cardiomyopathy (45 men and 8 women; mean age 48 +/- 14.3 years, New York Heart Association class 3.7 +/- 0.5), were treated by left ventricular reduction by partial left ventriculectomy (n = 37) or patch plasty (n = 3) and valve reconstruction alone (n = 13). The first 24 patients (group I) underwent ventriculectomy with or without valve reconstruction; the more recent 29 patients (group II) underwent left ventricular reduction (n = 16) or valve reconstruction alone (n = 13) on the basis of the intraoperative echocardiographic evaluation to observe changes of wall motion and thickness during cardiopulmonary bypass. RESULTS: Ischemic Group: Hospital mortality in elective (n = 26) and emergency (n = 7) operations was 4% and 43%, and 3 patients died in the late postoperative period. Mean New York Heart Association class and ejection fraction improved from 3.5 +/- 0.5 to 1.5 +/- 0.7 and from 23% +/- 7.7% to 36% +/- 8.6%, respectively. Left ventricular end-diastolic and end-systolic volume indexes decreased from 162 +/- 46 mL/m(2) to 110 +/- 39 mL/m(2) and from 130 +/- 47 mL/m(2) to 70 +/- 32 mL/m(2), respectively. Nonischemic Group: In 40 patients with left ventricular reduction, hospital mortality in elective (n = 33) and emergency (n = 7) operations was 6% and 86%, and 5 patients died in the late postoperative period. Mean New York Heart Association class and ejection fraction improved from 3.7 +/- 0.5 to 1.7 +/- 0.6 and from 18% +/- 6.4% to 31% +/- 5.9%. Left ventricular end-diastolic and end-systolic volume indexes decreased from 203 +/- 45 mL/m(2) to 110 +/- 37 mL/m(2) and from 164 +/- 40 mL/m(2) to 79 +/- 33 mL/m(2), respectively. In 13 patients undergoing valve reconstruction alone (12 mitral with or without tricuspid and 1 tricuspid plus left ventricular assist device), hospital mortality in elective (n = 9) and emergency (n = 4) operations was 0% and 50% with no late deaths. Mean New York Heart Association class and ejection fraction improved from 3.6 +/- 0.5 to 2.0 +/- 0.5 and from 22% +/- 6.0% to 30% +/- 14.5%, respectively. Mean left ventricular end-diastolic and end-systolic volume indexes decreased from 170 +/- 34 mL/m(2) to 150 +/- 50 mL/m(2) and from 140 +/- 38 mL/m(2) to 104 +/- 40 mL/m(2), respectively. Overall mortality decreased from 50% in group I to 10% in group II. The survival estimates at 2 years were 77% (confidence limits 57%-88%) in the ischemic group and 63% (confidence limits 47%-75%) in the nonischemic group (no significant difference). The analysis of our data showed that the factors influencing the surgical results for dilated cardiomyopathy were presence of severe mitral regurgitation, preoperative New York Heart Association functional class IV with emergency operation, and operative procedures with randomly performed partial left ventriculectomy without an intraoperative echo test. CONCLUSION: Endoventricular circular patch plasty, partial left ventriculectomy, and solo valve reconstruction can be performed with an acceptably low risk as elective operations. The selection of operative procedures in idiopathic dilated cardiomyopathy and avoidance of emergency surgery improved operative mortality and morbidity. Among patients who survived at least 1 year, there were no late deaths up to 30 months' follow-up.

Adolescent↗
PubMed2000

Late angiographic result of using the right gastroepiploic artery as a graft.

OBJECTIVE: The angiographic patency of the right gastroepiploic artery graft used for coronary artery bypass grafting was studied during the late (5-10 years) postoperative period. METHODS: Among 936 patients undergoing a gastroepiploic artery graft for coronary artery bypass grafting between 1986 and 1999, postoperative angiographic restudy was conducted on 685 patients within 1 year (mean, 2.2 months), on 102 patients between 1 and 5 years (mean, 2.3 years), and on 52 patients between 5 and 10 years (mean, 7.8 years). RESULTS: The patency rate of the gastroepiploic artery graft was 94%, 88%, and 83% in each restudy group. The cumulative patency rate estimated by the Kaplan-Meier method was 96.6% at 1 month, 91.4% at 1 year, 80.5% at 5 years, and 62.5% at 10 years. Causes of late occlusion were primary anastomotic stenosis and anastomosis to a less critically stenosed coronary artery. Once the gastroepiploic artery was perfectly anastomosed to the coronary artery, which has tight stenosis and good runoff, late patency was good, and new stenosis in both the gastroepiploic artery trunk and the anastomotic site was uncommon. CONCLUSION: The gastroepiploic artery graft can be used effectively for coronary artery bypass for the long term with proper target selection.

Arteries↗
PubMed2000

Lung cancer screening: minimum tube current required for helical CT.

PURPOSE: To investigate the minimum tube current required for helical computed tomography (CT) for lung cancer screening. MATERIALS AND METHODS: Thirty helical scans of the lung were obtained at effective tube currents of 50, 30, 20, 18, 12, 10, and 6 mAs in seven healthy volunteers. Computer-generated nodules 6 mm in diameter that showed ground-glass opacity were superimposed on the images. The image quality and detectability of nodules were evaluated subjectively by six observers. The SDs of measured CT numbers were calculated. The results were analyzed according to location in the lung. RESULTS: Compared with the subjective quality of images obtained at 50 mAs, the subjective quality of images obtained at 20 mAs was not significantly different. The detectability of nodules was not significantly degraded by reducing the tube current to 20 mAs in the upper zone of the lung, to 12 mAs in the middle zone, or to 18 mAs in the lower zone. The SDs at the apex and base of the lung were larger than those at other levels, and the difference became greater as the dose was reduced. CONCLUSION: The minimum tube current required for screening helical CT differs for different locations in the lung. An ideal CT protocol for the lung should permit the tube current to be changed during helical scanning.

Adult↗
PubMed2000

[Aortic valve/root replacement using a stentless bioprosthesis (Medtronic Freestyle valve)].

BACKGROUND: The purpose of the study is to assess the clinical and hemodynamic performance of aortic valve replacement (AVR) with the Freestyle bioprosthesis. METHODS: Twenty-one patients received AVR with a Freestyle aortic root bio-prosthesis between May 1998 and October 1999. Eighteen patients underwent AVR with subcoronary method and three patients with aortic root (full root) method. Patients were evaluated postoperatively at discharge by clinical examination and color Doppler echocardiography. RESULTS: There was one death due to multi-organ failure. No patients experienced valve deterioration, paravalvular leak, unacceptable hemodynamic performance, nor thromboembolic event. Excellent function is demonstrated by very low gradient (mean gradient 7.2 +/- 4.7 mmHg) through aortic valve and no significant aortic regurgitation (none: 11, trivial/mild: 10). All patients had been in New York Heart Association Functional Class III and IV preoperatively, and after surgery, 17 patients were in Class I, and 3 were in Class II. CONCLUSION: The Freestyle bioprosthesis has good clinical and hemodynamic performance without Coumadin. Further follow-up is required to evaluated valve durability.

Adult↗