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151.
A 74-year-old woman with mitral regurgitation secondary to ruptured chordae tendineae, complicated by a cleft in the posterior mitral leaflet and a severely calcified mitral annulus, underwent mitral valve repair by implantation of polytetrafluoroethylene chords and closure of the cleft, without the use of an annuloplasty ring. Immediately after the repair severe left ventricular outflow tract obstruction developed secondary to the systolic anterior motion of the mitral valve. Echocardiography identified the cause as functional, in the presence of a hypertrophic left ventricle with no significant preoperative intraventricular dynamic gradient. The obstruction was severe enough to render impossible the weaning of the patient from cardiopulmonary bypass. This problem was reversed by the infusion of beta-blocking agents into the extracorporeal circuit.  相似文献   
152.
STUDY OBJECTIVES: The aim of this study was to compare the relative efficacy in terms of improvement in symptoms and lung function of salmeterol/fluticasone propionate (SLM/FP) combination administered through the Diskus inhaler versus theophylline (THEO) added to FP Diskus in patients with stable chronic obstructive pulmonary disease (COPD). METHODS AND MEASUREMENTS: Eighty patients were randomized to receive 4 months of treatment in one of two treatment groups: (1) fixed combination of SLM 50 microg and FP 500 microg Diskus, 1 inhalation twice daily; or (2) FP Diskus 500 microg, 1 inhalation twice daily, plus oral titrated THEO twice daily. Patients attended the clinic before and after 4, 8, 12 and 16 weeks of treatment for evaluations of pulmonary function, and dyspnea, which was assessed using an analogic visual scale. Also the supplemental salbutamol use was measured. RESULTS:. Sixty-six patients completed the 4-month treatment period: 37 patients receiving SLM/FP and 29 patients receiving THEO+FP. Patients were withdrawn for various reasons, the most common of which were poor compliance with the protocol, exacerbation and GI events. A gradual increase in FEV(1) was observed with each treatment. Maximum significant increases in FEV(1) over baseline values that were observed after 4 months of treatment were as follows: SLM/FP 0.172 l (95% CI: 0.084-0.260) and THEO+FP 0.155 l (95% CI: 0.054-0.256). SLM/FP experienced significantly (p<0.05) greater improvements in dyspnea, and required significantly fewer supplemental salbutamol treatments than the THEO+FP group. CONCLUSIONS: Our results suggest that SLM/FP combination may provide substantial benefits in both physiologic and clinical outcomes in symptomatic patients with COPD. It also causes a more effective control than THEO+FP.  相似文献   
153.
Percutaneous closure of the left atrial appendage (LAA) is a new approach to the prevention of cardioembolic events in patients with atrial fibrillation. We implanted an LAA occlusion device (Amplatzer™ Cardiac Plug) in a 70-year-old woman via a transseptal approach. Upon her discharge from the hospital, a transthoracic echocardiogram showed stable anchoring of the device; 6 months after implantation, a routine transthoracic echocardiogram revealed migration of the occluder into the left ventricular outflow tract, in the absence of symptoms. We surgically removed the device from the mitral subvalvular apparatus and closed the LAA with sutures. This case shows that percutaneous LAA occlusion can result in serious adverse events, including device migration in the absence of signs or symptoms; therefore, careful follow-up monitoring is mandatory.  相似文献   
154.
Patients are at risk of mucositis and infections in the oral cavity during the neutropenic period after chemotherapy, which are significant causes of morbidity. In phase I/II studies with the haemopoietic growth factor granulocyte colony stimulating factor (G-CSF), a reduction in post-chemotherapy mucositis has been observed in addition to haematologic effects. To understand this phenomenon better in patients receiving G-CSF following high-dose chemotherapy with autologous bone marrow transplantation (ABMT), we studied the effects of G-CSF on levels of neutrophils recoverable from the oral cavity using a quantitative mouthrinse assay. In normal subjects, mouthrinses contained 472 +/- 329 x 10(3) neutrophils/mouthrinse. After chemotherapy followed by ABMT, mouthrinse neutrophil levels decreased to undetectable levels during the neutropenic period, but recovered 1-2 and 3-9 d before circulating neutrophil levels reached 0.1 and 1 x 10(9)/l respectively, whether or not patients received G-CSF. In patients who received G-CSF, the mean cumulative mucositis score was reduced from 35 +/- 9 to 21 +/- 12 (P < 0.05), and the maximum mean daily mucositis score was reduced from 2.8 +/- 0.5 to 1.7 +/- 0.9 (P < 0.01), compared to patients who did not receive G-CSF after ABMT. These studies provide in vivo evidence that neutrophils produced during G-CSF therapy are available to leave the circulation and enter tissues where their function is required for host defence. Since the usual temporal relationship between oral and peripheral blood neutrophil recovery was preserved during G-CSF administration after ABMT, these data support the hypothesis that the reduction in post-ABMT mucositis observed with G-CSF therapy may reflect a beneficial effect of G-CSF on the kinetics of oral mucosal neutrophil recovery in addition to the effect of G-CSF to accelerate peripheral blood neutrophil recovery.  相似文献   
155.
OBJECTIVES: First, to evaluate the prevalence of left ventricular (LV) hypertrophy, LV concentric remodelling and microalbuminuria in a selected sample of treated hypertensive patients with effective and prolonged clinic blood pressure (BP) control (BP < 140/90 mmHg). Second, to compare the prevalence of these markers of organ damage in patients with and without ambulatory BP (ABP) control, defined as average daytime BP < 132/85 mmHg). DESIGN AND METHODS: Fifty-eight consecutive hypertensive patients who attended our hypertension outpatient clinic over a period of 3 months and were regularly followed up by the same medical team were included in the study. Obesity, diabetes mellitus, history or signs of cardiovascular or renal complications and major noncardiovascular diseases were the exclusion criteria from the study. Each patient underwent 24 h ABP monitoring, echocardiography and 24 h urine collection for albumin measurement. RESULTS: The prevalence of LV hypertrophy (LV mass index > 125 g/m2 in both sexes), LV concentric remodelling (relative wall thickness > 0.45) and microalbuminuria (urinary albumin excretion < 300 mg/ 24 h) in this selected group of patients (32 men, 26 women; mean age 53 +/- 9 years; mean clinic BP 122 +/- 9/ 78 +/- 6 mmHg) was markedly low (6.9, 8.6 and 5.1%, respectively). The 26 patients with effective ABP control (group I) were similar to the 32 patients without effective ABP control (group II) in age, gender, body surface area, clinic BP, smoking habit, glucose, cholesterol and creatinine plasma levels. Prevalence of LV hypertrophy, LV concentric remodelling and microalbuminuria was lower in group I than in group II (0 versus 12.9% P< 0.01, 7.7 versus 9.4% NS, 3.8 versus 6.2% NS, respectively). CONCLUSIONS: This study demonstrates that nonobese, nondiabetic hypertensive patients with an effective clinic BP control have a very low prevalence of target organ damage and that LVH is present only in individuals with insufficient ABP control.  相似文献   
156.
BACKGROUND: It has been shown that aging and arterial hypertension are both associated with an increased prevalence of carotid structural abnormalities, such as intima-media (IM) thickening or plaques, which are a powerful independent predictor of cardiovascular (CV) events. We investigated the impact of carotid IM thickening in profiling the absolute CV risk stratification according the 1999 World Health Organization/International Society of Hypertension (WHO/ISH) guidelines in elderly hypertensive patients. METHODS: Two hundred and thirty untreated elderly patients (>65 years) referred to our outpatient hospital clinic were included in the study. They underwent the following procedures: (i) medical history, physical examination and clinic blood pressure measurement; (ii) routine blood chemistry and urine analysis; (iii) electrocardiogram. The risk was initially stratified according to the routine procedures indicated by WHO/ISH guidelines and subsequently reassessed by adding the results of carotid ultrasonography (IM thickening as diffuse IM thickness >0.9 and <1.3 mm). RESULTS: According to routine classification 56% (=129) were medium-risk patients, 29% (n = 67) high-risk and 15% (n = 34) very-high-risk patients. The overall prevalence of carotid IM thickening was 54% (49% in medium-risk vs 60% in high or very high-risk patients, p < 0.05). A marked change in risk stratification was observed when IM thickening was taken in consideration: medium-risk patients decreased to 29% and high-risk rose to 56% (p < 0.01). CONCLUSIONS: Ultrasound assessment of large artery damage is extremely useful for a more accurate estimate of global CV risk in elderly hypertensives, because stratification based on diagnostic routine procedures can underestimate the overall risk in a large fraction of medium-risk subjects.  相似文献   
157.
OBJECTIVE: To evaluate the reliability of contrast-unenhanced power Doppler (CUPD) and contrast-enhanced power Doppler (CEPD) ultrasound (US) assessment of synovial vascularity of knee joint synovitis by prospective comparison with the "gold standard," arthroscopy. METHODS: A total of 18 knees of 17 patients with refractory rheumatoid and psoriatic knee joint synovitis were examined by US. Recognition of PD synovial vessel flow and its spatial arrangement in relation to the pannus/cartilage interface (P/CI) or fluid/synovium interface (F/SI) were studied by CUPD- and CEPD-US after a single intravenous bolus of galactosel palmitic acid (Levovist). Arthroscopy video recordings were reanalyzed by computer image analysis to assess synovial vascular marking. CUPD and CEPD flow signal scores were compared with each other and with corresponding vascular marking scores. Using villous vascular marking as reference, CUPD and CEPD sensitivity and specificity were measured. Interobserver variability was evaluated. RESULTS: Compared with the unenhanced PD method, contrast administration increased the PD flow signal score in 13/18 knees (72.2%), allowing increased detection of F/SI PD flow signal configuration (p < 0.018) and of the coexistence of P/CI and F/SI PD imaging (p < 0.0078). With arthroscopy as reference, contrast-enhanced PD was found to be more useful than the unenhanced method, showing more reproducible PD signal scores (p = 0.05 vs p = nonsignificant), as well as higher sensitivity (80% vs 30%), but lower specificity (62% vs 87%), in the recognition of increased vascularity of synovial villi. Interobserver agreement was 100%. CONCLUSION: The prospective comparison with arthroscopy showed the reliability of the CEPD method in synovial vessel recognition and its potential clinical usefulness in assessment of knee joint synovitis.  相似文献   
158.
Autoimmune hemolytic anemia (AIHA) in children is sometimes characterized by a severe course, requiring prolonged administration of immunosuppressive therapy. Rituximab is able to cause selective in vivo destruction of B lymphocytes, with abrogation of antibody production. In a prospective study, we have evaluated the use of rituximab for the treatment of AIHA resistant to conventional treatment. Fifteen children with AIHA were given rituximab, 375 mg/m(2)/dose for a median of 3 weekly doses. All patients had previously received 2 or more courses of immunosuppressive therapy; 2 patients had undergone splenectomy. After completing treatment, all children received intravenous immunoglobulin for 6 months. Treatment was well tolerated. With a median follow-up of 13 months, 13 patients (87%) responded, whereas 2 patients did not show any improvement. Median hemoglobin levels increased from 7.7 g/dL to a 2-month posttreatment level of 11.8 g/dL (P <.001). Median absolute reticulocyte counts decreased from 236 to 109 x 10(9)/L (P <.01). An increase in platelet count was observed in patients with concomitant thrombocytopenia (Evans syndrome). Three responder patients had relapse, 7, 8, and 10 months after rituximab infusion, respectively. All 3 children received a second course of rituximab, again achieving disease remission. Our data indicate that rituximab is both safe and effective in reducing or even abolishing hemolysis in children with AIHA and that a sustained response can be achieved in the majority of cases. Disease may recur, but a second treatment course may be successful in controlling the disease.  相似文献   
159.
BACKGROUND: The purpose of our study was to investigate whether continuous venovenous hemodiafiltration (CVVHDF) concomitant with radiological procedures (RxP) was feasible, well tolerated and could significantly remove iodinated contrast media (CM). METHODS: 26 patients with various degrees of renal insufficiency who were submitted to RxP were included in the study. The CVVHDF session was started immediately before CM administration. All the patients were evaluated for feasibility and tolerability; furthermore a pharmacokinetic study was done on 12 patients to calculate the amount of CM eliminated. The baseline incidence of CM nephropathy was studied in 25 consecutive historical controls. RESULTS: The CM administered was 208 +/- 146 g; the fractional removal of CM was 9.2 +/- 4.9% during RxP and 30.9 +/- 20.7% during the whole CVVHDF session. Hemodynamic tolerance was excellent. The incidence of CM nephropathy in the experimental and control groups was 37 and 24%, respectively. CONCLUSIONS: CVVHDF during RxP is feasible and well tolerated but ioversol removal is modest. This fact together with the high incidence of renal function impairment, the complexity of the procedure and its intrinsic risks, and the large amount of resources needed discourage the routine use of CVVHDF as a prophylactic tool to avoid CM nephropathy.  相似文献   
160.
Identification of the hemangioblast in postnatal life   总被引:28,自引:11,他引:28  
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