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1.
Cross-sectional echocardiography utilizing the apical and longitudinal right ventricular inflow tract views was used to investigate the tricuspid valve in 64 patients with mitral valve prolapse and 16 controls who had no angiographic or echocardiographic evidence of mitral valve prolapse. The tricuspid valve leaflets and their coaptation point in systole were found to be below (towards the right ventricular apex) the level of the tricuspid valve ring in systole in all controls. Tricuspid valve prolapse, defined as the leaflet(s) of the tricuspid valve lying above the tricuspid valve ring level within the right atrium, was seen in 31/64(48 percent) of patients with mitral valve prolapse. The right ventricular inflow tract view demonstrated tricuspid valve prolapse most readily compared to the apical view, and 29 of the 31 patients with tricuspid valve prolapse had prolapse of at least two leaflets of the tricuspid valve. The 31 patients with both mitral and tricuspid valve prolapse, when compared to the 33 patients with mitral valve prolapse alone, had more symptomatology and abnormal physical findings.  相似文献   

2.
PURPOSE: Physiologic observations with blood flow waveform analysis and pressure measurements can document the severity of lower extremity arterial disease. Segmental blood pressures (SEGPs) taken at the thigh, calf, and ankle are commonly used, but their utility has seldom been studied. We quantified improvements in accuracy compared with arteriography when ankle pressures alone (ABI) or SEGP data were added to velocity waveforms obtained by Doppler ultrasound. METHODS: Continuous-wave Doppler velocity waveforms were recorded at common femoral (CFA), popliteal (POP), and dorsal pedal and posterior tibial (TIB) arterial levels. Systolic SEGP data were obtained with appropriately sized upper thigh, upper calf, and ankle cuffs. Waveforms, waveforms plus ABI, and waveforms plus SEGP data from 81 patients were randomly interpreted by 14 technologists or physicians from four institutions blinded to clinical and arteriographic data. Arteriograms were assigned negative or significant, severe (>75% diameter stenosis) values for four segments: iliofemoral (CFA), superficial femoral (SFA), popliteal (POP), and infrapopliteal (TIB) arteries. A total of 9072 segmental interpretations were analyzed. RESULTS: Compared with arteriography, the accuracy of waveform analysis was 83% for severe disease at and proximal to the CFA, 79% for SFA disease, 64% for POP disease, and 73% for TIB disease. Adding ABI improved the accuracy significantly (p < 0.01) to 88% (CFA), 86% (SFA), 70% (POP), and 85% (TIB). Accuracy was inferior when SEGP data replaced ABI: 86% (CFA), 85% (SFA), 70% (POP), and 80% (TIB). CONCLUSIONS: ABIs significantly improved Doppler waveform accuracy at all levels. Compared with ABI, the addition of segmental pressure to waveform data failed to improve accuracy. Pressure measurements above the ankle may lack cost effectiveness and clinical utility.  相似文献   

3.
PURPOSE: We evaluated the long-term results of arterial bypass surgery in impotent men carefully selected for nonatherosclerotic arterial vascular disease. MATERIALS AND METHODS: During a 7-year period only 11 of 1,352 impotent men (0.8%) were selected as ideal candidates for arterial vascular surgery. Initial evaluation included history, physical examination and a screening pharmacological erection test. Duplex ultrasonography was performed in patients who failed to respond adequately to pharmacological stimulation and were believed to be potential candidates for vascular surgery. Further evaluation included formal nocturnal sleep laboratory testing, dynamic infusion cavernosometry and arteriography. Dorsal artery bypass was performed in 9 patients and arterialization of the deep dorsal vein was done in 2. RESULTS: Average followup was 50 months (range 12 to 84). Initial followup duplex ultrasonography revealed a significant increase in cavernous artery peak systolic blood flow velocity (p < 0.001) and patent arterial anastomoses in all but 1 patient. The initial success rate without supplemental injection therapy was 82% and the final success rate was 64%. Even with long-term followup, 91% of the patients were improved from baseline, and were sexually active with (27%) or without (64%) injection therapy. CONCLUSIONS: Arterial bypass surgery can be successful in select impotent patients without generalized atherosclerosis or other risk factors for impotence. Further refinement of screening parameters may improve patient selection and long-term results of vascular surgery.  相似文献   

4.
5.
Total of 123 patients (mean age: 63.8 +/- 7.3 years, (male/female 65/35 percent) underwent mitral valve surgery combined with coronary artery bypass grafting during a seven year period. Preoperatively 12% of them belonged to NYHA functional class II, 54% to class III, 29% to class IV and 3% was operated under emergency conditions. The mitral valve lesion was most frequently either ischaemic (45%) or rheumatic (33%) in origin. Left ventricle function was moderately decreased in 18% and severely damaged in 3% of the patients as documented by preoperative ventriculography. Coronary surgery was performed in all cases with an average number of distal anastomosis of 2.2 +/- 1.1 per patient. The hospital mortality was 13%. Risk factors for early and late mortality were determined by univariate and multivariate analysis. Advanced preoperative functional class and decreased left ventricular function or ischaemic etiology were identified as significant risk factors for early mortality. The patients were followed for an average of 33 +/- 25 months. The majority of them experienced significant functional improvement postoperatively with 69% belonging to NYHA class I or II. The late survival for the 107 hospital survivors was 94.7% at one year, and 84.7% at five years, respectively. Late survival was independently determined by preoperative functional class or previous myocardial infarction. Freedom from ischemic and valve related complications at five years was 95% and 71.2% respectively. 58.2% of the hospital survivors were in functional class I or II and free of any valve related or ischemic complications at the end of the fifth follow up year.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
Renin activity (RA), concentration of aldosterone and hydrocortisone in plasma were measured by radioimmunoassay in 78 males with arterial hypertension living in the Far North. RA and aldosterone concentrations were high in patients with borderline arterial hypertension irrespectively of hemodynamic type of the disease. Hydrocortisone levels in them were normal. In hypertension stage I and II RA and hydrocortisone concentrations were normal, while aldosterone levels have risen. Renin-aldosterone index showed high RA in all hemodynamic types of hypertension.  相似文献   

7.
PURPOSE: Results of percutaneous transluminal angioplasty (PTA) in selected cases have been reported to be equal or superior to those of arterial bypass graft surgery, with a lower morbidity and mortality. We performed PTA of stenotic or occlusive lesions in patients with limb-threatening ischemia, hoping to improve our overall success and decrease morbidity in this group of patients. The results of PTA in the limb-salvage setting was evaluated. METHODS: From 1992 to 1995, 307 PTAs were performed in 257 patients. One hundred sixty-one (63%) patients had diabetes mellitus, and 32 (12%) patients had renal failure. All patients were evaluated by means of pulse volume recordings and ankle brachial indices at 1 and 6 weeks after PTA and at 3 month intervals thereafter. Seventeen patients (9%) were lost to follow-up. The continued success or failure of PTA was defined by means of noninvasive vascular laboratory criteria, patency by means of pulse examination, the need for subsequent bypass grafting across the index lesion, and limb salvage. RESULTS: The 1-year patency rates for external iliac PTAs (56%) were significantly lower (P <.05) than those for common iliac PTAs (87%). Infrainguinal PTAs at the femoral, popliteal, and tibial level had 1-year patency rates of less than 15%. CONCLUSION: Common iliac artery PTA is justified in most cases in which it is feasible. However, when PTAs are performed below the inguinal ligament, the results are markedly worse. One-year patency rates of PTA in this group of patients with threatened limbs are inferior to the patency rates of arterial bypass grafts, even when these bypasses are performed with a prosthetic material. PTA should not be considered as a primary treatment modality for patients with infrainguinal arterial occlusive disease who also have limb-threatening ischemia, except in unusual circumstances.  相似文献   

8.
Impaired gut mucosal perfusion has been reported during cardiopulmonary bypass. To better define the adequacy of gut blood flow and oxygenation during cardiopulmonary bypass, we measured overall gut blood flow and ileal mucosal flow and their relationship to mucosal pH, mesenteric oxygen delivery and oxygen consumption in immature pigs (n = 8). Normothermic, noncross-clamped, right atrium-to-aorta cardiopulmonary bypass was maintained at 100 ml/kg per minute for 120 minutes. Animals were instrumented with an ultrasonic Doppler flow probe on the superior mesenteric artery, a mucosal laser Doppler flow probe in the ileum, and pH tonometers in the stomach, ileum, and rectum. Radioactive microspheres were injected before and at 5, 60, and 120 minutes of cardiopulmonary bypass for tissue blood flow measurements. Overall gut blood flow significantly increased during cardiopulmonary bypass as evidenced by increases in superior mesenteric arterial flow to 134.1% +/- 8.0%, 137.1% +/- 7.5%, 130.3% +/- 11.2%, and 130.2% +/- 12.7% of baseline values at 30, 60, 90, and 120 minutes of bypass, respectively. Conversely, ileal mucosal blood flow significantly decreased to 53.6% +/- 6.4%, 49.5% +/- 6.8%, 58.9% +/- 11.6%, and 47.8% +/- 10.0% of baseline values, respectively. Blood flow measured with microspheres was significantly increased to proximal portions of the gut, duodenum and jejunum, during cardiopulmonary bypass, whereas blood flow to distal portions, ileum and colon, was unchanged. Gut mucosal pH decreased progressively during cardiopulmonary bypass and paralleled the decrease in ileal mucosal blood flow. Mesenteric oxygen delivery decreased significantly from 67.0 +/- 10.0 ml/min per square meter at baseline to 42.4 +/- 4.6, 44.9 +/- 3.5, 46.0 +/- 3.6, and 42.9 +/- 3.9 ml/min per square meter at 30, 60, 90, and 120 minutes of bypass. Despite the decrease in mesenteric oxygen delivery, mesenteric oxygen consumption increased progressively from 10.8 +/- 1.4 ml/min per square meter at baseline to 13.4 +/- 1.2, 15.9 +/- 1.2, 16.7 +/- 1.4, and 16.6 +/- 1.54 ml/min per square meter, respectively. We conclude that gut mucosal ischemia during normothermic cardiopulmonary bypass results from a combination of redistribution of blood flow away from mucosa and an increased oxygen demand.  相似文献   

9.
PURPOSE: To determine the value of pretransplant studies in predicting day 100 nonrelapse toxic mortality following high-dose therapy. PATIENTS AND METHODS: A retrospective review of 383 consecutive hematopoietic stem-cell transplants was performed with attention to toxic mortality and pretransplant factors. Univariate log-rank analysis was used to yield the most significant cut-off values for individual factors. Multivariate analysis using Cox proportional hazards regression determined factors independently predictive of early toxic death. RESULTS: Nonrelapse toxic mortality before day 100 occurred in 23 of 383 (6.0%) transplant recipients. Factors associated with an increased risk of toxic death by univariate analysis included forced expiratory volume in 1 second (FEV1) less than 78% of predicted (P = .0002), allogeneic versus autologous transplant (P = .0003), diffusion capacity of carbon monoxide less than 52% of predicted (P = .002), serum creatinine concentration greater than 1.1 mg/dL (P = .003), Eastern Cooperative Oncology Group performance status greater than 0 (P = .006), preparative regimen containing total-body irradiation versus chemotherapy alone (P = .006), marrow versus blood stem cell (P = .01), serum ALT greater than 50 IU/L (P = .02), diagnosis of hematologic disorder versus solid tumor (P = .06), serum bilirubin level greater than 1.1 mg/dL (P = .08), left ventricular ejection fraction (P = .09), and growth factor use (P = .09). In the multivariate model, transplant type (relative risk, 4.2), FEV1 (relative risk, 4.5), performance status (relative risk, 3.7), serum creatinine (relative risk, 3.8), and serum bilirubin (relative risk, 3.7) were found to be independent predictors of early toxic mortality. CONCLUSION: The pretransplant evaluation is a useful tool to identify patients at risk for early toxic mortality following high-dose therapy.  相似文献   

10.
OBJECTIVE: To evaluate the electrical resistance to current conduction of different guidewires used routinely in endourology and thus determine the risk of short circuits between the active electrode and the guide. MATERIALS AND METHODS: Using a standard resistance meter, the electrical resistance of four different types of guidewires was measured. Pure stainless-steel, polytetrafluoroethylene (PTFE)-painted, PTFE-sheathed and hydrogel-sheathed guidewires were tested, both when new and after mechanical abrasion of the external layer to reproduce their condition after use. RESULTS: The pure stainless-steel guidewire had no resistance to electrical current. The electrical insulation of the PTFE-painted guidewires was poor and was eliminated by mechanical abrasion of the paint. New PTFE-sheathed and hydrogel-sheathed guidewires had a safe electrical resistance (> 10 K omega) but this insulation was easily eliminated by mechanical abrasion of the external layer. CONCLUSIONS: To minimize the risk of electrosurgical adverse effects during a guidewire-assisted endoscopic procedure, the operator should preferably use a new guidewire for each procedure, use sheathed guidewires and ensure that the guidewire is in good condition, or cover it with a ureteric catheter, before applying current.  相似文献   

11.
Striatal neurons from E15 rat embryos were dissociated, plated at low cell density on polyornithine or on astrocyte monolayers derived from the striatum (homotopic) or mesencephalon (heterotopic), and cultured in a chemically defined medium. After 2 to 10 days neurons could be divided in 3 classes according to their cell body diameter: small, medium or large. The percentage of small neurons which was very high 60% for GABAergic neurons on polyornithine after 2 days in vitro was reduced to 35% on mesencephalic astrocytes and to less than 20% on striatal astrocytes. The decrease in the number of small cells was paralleled by an increase in the number of multipolar medium size cells whereas the percentages of bipolar medium size and large neurons remained constant (55 and 4% respectively). All results obtained with the general neuronal population were replicated with the GABAergic sub-population which accounted for more than 50% of total neuronal population. These experiments confirm the beneficial influence of homotopic astrocytes on neuronal differentiation and on dendrite growth.  相似文献   

12.
13.
Growth of the thermoacidophilic Gram-positive bacterium Alicyclobacillus acidocaldarius strain ATCC 27009 on maltose resulted in the increased production of a protein with apparent molecular mass of 40 kDa. By metabolic labelling with 14C-palmitic acid, the 40-kDa protein was identified as a lipoprotein. The protein exhibited maltose-binding activity at pH 3.5, as demonstrated by chromatography on cross-linked amylose. Partial amino acid sequence analysis revealed that the 40-kDa protein corresponds to the product of an open reading frame downstream from the amylase gene (amy) that displays similarity to enterobacterial maltose-binding proteins.  相似文献   

14.
233 undergraduates (162 women and 71 men) completed a demographics questionnaire and measures of career-decision-making (CDM) self-efficacy (K. M. Taylor and N. E. Betz, 1983), CDM attitudes (J. O. Crites, 1978), and CDM skills (D. E. Super et al, 1981). Results revealed that CDM self-efficacy was moderately and positively related to CDM attitudes and age of participants (p?  相似文献   

15.
Obtained both work- and socially-oriented peer nominations from 117 inexperienced life insurance agents at the end of a 3-wk training course. These nominations, along with age, monthly starting pay, and final school grade were related to objective measures of sales success at 6-mo and 1-yr intervals. Only the peer nomination scores proved to be significant at both a statistical and practical level. Analysis of the peer nominations led to the identification of 3 factors which accounted for 88% of the total variance. Only 1 of these factors, the ability to form close personal relationships, proved to be significantly related to the 1-yr criteria measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
With a newly developed quadrupole mass spectrometer several blood gas partial pressures are recorded simultaneously and continuously. In the mass filter the separation of the ions to be detected takes place in a hyperbolic electric field with variable direct and alternating voltages with a constant frequency of 2.4 MHz. For blood gas analysis a fully relaxed experimental animal was artifically ventilated and provided with arterial and venous catheters. Each catheter consisted flexible steel tubing (external diameter 0.6 mm) slotted near the end and covered with a silicone rubber membrane. The distance from the measuring tip to the mass spectrometer was 150 cm. Experiments with blood, in vivo equilibrated with gas mixtures, showed good reproducibility; the mean error of the helium partial pressure, for example, was less than 4%. During respiration using a gas mixture with 40% argon, the time constant t63% was found to be 55 s for the whole experimental arrangement including the experimental animal.  相似文献   

17.
OBJECTIVE: The purpose of this study was to determine predictors of posttraumatic stress disorder (PTSD) in health care workers exposed to a disaster, in order to facilitate early case identification and prevention of subsequent morbidity. METHOD: Following an air disaster, 355 military medical health care workers were studied over an 18-month follow-up period. Measures included assessment of peritraumatic reactions associated with the disaster, the frequency of other stressful events after the disaster, and standard PTSD rating scales at 6, 12, and 18 months. RESULTS: Multivariate logistic regression of data on health care workers who cared for victims of the air disaster showed that PTSD was more likely to develop in those who had not completed college, those who had worked with burn victims, those who had experienced more stressful life events in a period of approximately 6 months following the disaster, and those who experienced emotional numbness immediately after the disaster. CONCLUSIONS: Results suggest that lower levels of education, exposure to grotesque burn injuries, stressful life events following exposure, and feelings of numbness following exposure are useful predictors of subsequent development of PTSD.  相似文献   

18.
PURPOSE: This study tests the clinical value of femoral artery pressure measurements by analysis of the relationship between iliac artery pressure gradients (PGs) and both femorofemoral bypass graft patency and the hemodynamic changes produced in the donor and recipient limbs. METHODS: Systemic and donor femoral artery systolic and mean pressures were measured during surgery at rest and during papaverine-induced hyperemia before 94 femorofemoral bypasses. Ankle/brachial (A/B) pressure ratios and pulse volume recordings (PVRs) were measured before and early after surgery. Donor iliac artery stenosis was 25% +/- 23% (mean +/- 1 SD). Follow-up was 23+/- 20 months. RESULTS: Eight bypasses failed at 21 +/- 20 months. Patients with failed bypasses had a resting systolic and mean PG of 23 +/- 22 mm Hg and 5 +/- 7 mm Hg, respectively, compared with 10 +/- 11 mm Hg (p = 0.007) and 1 +/- 2 mm Hg (p = 0.001) for the 86 patent bypasses. Donor limb A/B ratios and PVRs decreased 9% +/- 5% and 15% +/- 14%, respectively, had a linear regression slope less than 0 (p < 0.05) with resting and hyperemic PGs, and correlated best with resting PGs (p < 0.05). Recipient limb A/B ratios and PVRs increased 86% +/- 48% and 191% +/- 111%, respectively, had a linear regression slope greater than 0 (p < 0.05) with all resting and hyperemic PGs, and correlated best with hyperemic systolic PGs (p < 0.05). However, all regressions had a large SD, wide 95% confidence limit, and a low correlation coefficient. Sensitivity-specificity receiver-operating characteristic curves for optimal PG criteria for both graft failure and donor limb hemodynamic impairment are weak, with an accuracy of 50% to 75%. Recommended criteria for not performing a femorofemoral bypass are a resting systolic PG of 28 mm Hg or greater or a resting mean PG of 6 mm Hg or greater. CONCLUSIONS: Although iliac artery PGs correlate with graft failure and both the degree of donor limb hemodynamic impairment and recipient limb improvement, the large variability in PGs between patients with similar outcomes and the low accuracy of optimal PG criteria indicate that they have limited clinical value in decision making.  相似文献   

19.
When deobstruction by Fogarty catheter fails, the axillofemoral bypass can be considered as a therapeutic solution of the acute ischaemia of the limb. The authors discuss a case occurred in their experience and focus their attention on the therapeutic potentiality of this kind of revascularization. As a matter of fact it is important to consider that the operation should not only eliminate the acute ischaemia, but also correct the atherosclerotic lesions that led to it. Therefore, if deobstruction by Fogarty catheter does not restore a good inflow, in high risk patients with acute arterial thrombosis of the limb, there is a well indication for extra-anatomic revascularization.  相似文献   

20.
BACKGROUND: Identification of viable but hibernating myocardium remains a relevant issue in the current era of myocardial revascularization. Echocardiography can be helpful in detecting reversible contractile dysfunction and optimizing the selection of patients for coronary bypass surgery. METHODS AND RESULTS: Eighty-four consecutive candidates for bypass surgery with chronic multivessel coronary artery disease were screened, and 60 were included in this prospective study. Preoperative evaluation of a reversible contractile dysfunction in asynergic myocardial regions was performed by dobutamine infusion at 5 (low dose) and 10 (intermediate dose) microg x kg(-1) x min(-1) with each stage lasting at least 5 minutes; postextrasystolic potentiation (PESP), with a coupling interval ranging from 500 to 300 ms with a progressive 10-ms decrease; or a combination of both dobutamine infusion and PESP. Sensitivity (92% versus 86%) and predictive accuracy (89% versus 84%) were higher with PESP than dobutamine (P=.009 and P=.001, respectively), but the combination did not improve sensitivity or accuracy. Dobutamine induced ischemic dysfunction in 15% of patients at the intermediate dose; however, the low dose resulted in loss of sensitivity. CONCLUSIONS: PESP echocardiography is a useful and cost-effective method to identify viable myocardium in patients with multivessel coronary disease undergoing revascularization and is more sensitive and accurate than dobutamine infusion.  相似文献   

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