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81.

Background

Patients on chronic hemodialysis (HD) are recognized as a high‐risk group for adverse events after percutaneous coronary intervention, and whether drug‐eluting stents (DES) are associated with improved outcomes over bare metal stents (BMS) is still uncertain. The purpose of this study was to assess the efficacy of DES compared with BMS at short‐ and long‐term follow‐up (FU) in an unselected sample of HD patients.

Methods and Results

In the time period 2005–2010, consecutive patients on chronic HD treated with percutaneous coronary intervention (PCI) and stent implantation were retrospectively selected and analyzed. A total of 169 patients were selected, 77 treated exclusively with BMS and 92 exclusively with DES. Baseline clinical characteristics were similar in the 2 groups as well as the number of treated vessels, treated lesions, and the stent per patient ratio. At longest available FU, no difference between the 2 study groups was found in terms of cardiac death (18.2% vs 16.3%, P = 0.83), myocardial infarction (2.5% vs 8.6%, P = 0.09), cerebrovascular accidents (0% vs 1.1%, P = 0.98), and target vessel revascularization (TVR) (9.1% vs 16.3%, P = 0.17). Major adverse cardiac and cerebrovascular events‐free survival at 1,500 days in the BMS and DES groups was 57.6% and 50.9% (P = 0.11), respectively.

Conclusions

PCI in patients on chronic HD treatment is associated with a high incidence of adverse events at FU, mainly represented by death. In our study, the use of DES was not associated with a reduction of target lesion revascularization (TLR) and TVR.
  相似文献   
82.
The aim of this study was to evaluate the possible prognostic relevance of thymidine kinase serum levels (s-TK), an indirect marker of proliferative activity, in myelodysplastic syndromes (MDS). S-TK levels were monitored by means of a radioenzyme assay in 90 patients affected by MDS (22 refractory anaemia, RA; 17 RA with ring sideroblasts, RARS; 21 RA with blast excess, RAEB; 15 RAEB in transformation, RAEB-T; 15 chronic myelomono-cytic leukaemia, CMMoL). Mean s-TK levels (U//tl) measured at diagnosis were 11–9 –12–6 for RA, 11–4–13'6 for RARS, 19–9 – 28–4 for RAEB, 39–6 – 34–3 for RAEB-T and 77–7 – 69–7 for CMMoL (normal values <5U//LI1). With the only exception of a weak relationship with lactate dehydrogenase, no correlation was found between initial s-TK values and other clinical or laboratory parameters, such as age, haemoglobin, white blood cell or platelet count, percentage of bone marrow blasts. MDS patients with s-TK >38 V/fA , a cut-off level selected by means of ROC statistical analysis, showed a significantly shorter survival than those with s-TK <38U//xl (8–2 v 37–4 months, respectively; P < 0–0001). In particular, transformation in acute myeloid leukaemia (AML) occurred in 17/21 (81%) of patients with s-TK >38U//d and 9/69 (13%) of those with lower levels at diagnosis (P < 00001), independently of FAB subtype. High s-TK levels were also useful to predict evolution in AML during the course of the disease in patients with normal initial values. Multivariate analysis confirmed the independent prognostic value of s-TK on both overall survival and risk of acute transformation. We conclude that s-TK may be an important prognostic factor in MDS, strongly correlated with development of AML.  相似文献   
83.
Pulmonary thromboembolism presents in two clinical subsets: acute pulmonary embolism (PE) with or without right heart thrombi or paradoxical embolism and chronic thromboembolic pulmonary hypertension (CTEPH). Both PE and CTEPH have been underdiagnosed and carry high mortality rates. Acute massive PE is a hemodynamic entity leading to right ventricular overload readily identified with the use of transthoracic echocardiography. Transesophageal echocardiography (TEE) is a noninvasive bedside technique that has high diagnostic accuracy for the detection of central pulmonary thromboembolism. Due to the high prevalence of central pulmonary thromboembolism in acute PE, TEE is a useful method to provide the necessary proof for the institution of thrombolytic therapy. In the subset of patients with acute PE combined with right heart thrombi or paradoxical embolism, TEE is the technique of choice to guide surgery. CTEPH presents as primary pulmonary hypertension, but it has become a surgically curable disease. TEE is a fast, fairly sensitive, and highly specific diagnostic bedside modality to select surgical candidates with CTEPH. TEE should become a routine test in patients with suspected massive acute PE, suspected right heart thrombi, or paradoxical embolism associated with acute pulmonary embolism and in patients with primary pulmonary hypertension to select those having CTEPH who are suitable for surgery.  相似文献   
84.
Is the Outcome of Coronary Stenting Worse in Elderly Patients?   总被引:1,自引:0,他引:1  
Initial reports of percutaneous transluminal coronary angioplasty (PTCA) in the elderly (≥: 75 years) showed a significantly lower primary success rate, higher in-hospital mortality, and a higher risk of emergency or elective coronary artery bypass graft (CABG) compared to younger patients. There are few data concerning acute outcomes and clinical follow-up after the use of coronary stenting in the elderly compared to < the 75-year-old age group. We evaluated 82 elderly patients and 280 younger patients who received Palmaz-Schatz stents during 1995, at a time when high pressure deployment and antiplatelet therapy was routinely used. The success rate and acute major complications were not significantly different between the elderly and younger patients. Clinical events (death, myocardial infarction [MI], repeat PTCA, or CABG) during 6-month follow-up were also not significantly different. Coronary stenting in the elderly can be carried out with a high success rate and low incidence of acute major complications. Thus, short-term clinical outcomes in elderly patients appear similar to results obtained in younger patients.  相似文献   
85.
To determine whether patients with a HLA-identical sibling donor have a better outcome than patients without a donor, an analysis on the basis of intention-to-treat principles was performed within the framework of the EORTC-GIMEMA randomized phase III AML 8A trial. Patients in complete remission (CR) received one intensive consolidation course. Patients with a histocompatible sibling donor were then allocated allogeneic bone marrow transplantation (alloBMT), the patients without a donor were randomized between autologous BMT (ABMT) and a second intensive consolidation (IC2). 831 patients <46 years old and alive >8 weeks from diagnosis were included. HLA typing was performed in 672 patients. AlloBMT was performed during CR1 in 180 (61%) out of 295 patients with a donor. Another 38 patients were allografted: five in resistant disease, 14 during relapse and 19 in CR2. ABMT was performed in 130 (34%) out of 377 patients without a donor in CR1, in six (2%) patients during relapse and in 38 (10%) patients during CR2. The disease-free survival (DFS) from CR for patients with a donor was significantly longer than for patients without a donor (46% v 33% at 6 years; P = 0.01, RR 0.78, 95% confidence interval 0.63–0.96). The overall survival from diagnosis for patients with a donor was longer, but not statistically significant, than for patients without a donor (48% v 40% at 6 years; logrank P = 0.24). When patients were stratified according to prognostic risk groups, the same trend in favour of patients with a donor was seen for survival duration and the DFS remained significantly longer for this group of patients.  相似文献   
86.
87.
Comparing ICD Implantation with and Without Intraoperative Defibrillation Testing. Introduction: The need to perform defibrillation testing (DT) at the time of implantable cardioverter defibrillator (ICD) insertion is controversial. In the absence of randomized trials, some regions now perform more than half of ICD implants without DT. Methods: During the last year of enrolment in the Resynchronization for Ambulatory Heart Failure Trial, a substudy randomized patients to ICD implantation with versus without DT. Results: Among 252 patients screened, 145 were enrolled; 75 randomized to DT and 70 to no DT. Patients were similar in terms of age (65.9 ± 9.3 years vs 67.9 ± 8.9 years); LVEF (24.7 ± 4.6% vs 23.6 ± 4.6%), QRS width (154.8 ± 23.5 vs 155.8 ± 23.6 ms), and history of atrial fibrillation (5% vs 6%). All 68 patients in the DT arm tested according to the protocol achieved a successful DT (≤25 J); 96% without requiring any system modification. No patient experienced perioperative stroke, myocardial infarction, heart failure (HF), intubation or unplanned ICU stay. The length of hospital stay was not prolonged in the DT group: 20.2 ± 26.3 hours versus 21.3 ± 23.0 hours, P = 0.79. One patient in the DT arm had a failed appropriate shock and no patient suffered an arrhythmic death. The composite of HF hospitalization or all‐cause mortality occurred in 10% of patients in the no‐DT arm and 19% of patients in the DT arm (HR = 0.53, 95% CI: 0.21–1.31, P = 0.14). Conclusions: In this randomized trial, perioperative complications, failed appropriate shocks, and arrhythmic death were all uncommon regardless of DT. There was a nonsignificant increase in the risk of death or HF hospitalization with DT. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1313‐1316, December 2012)  相似文献   
88.
Modulation of the allergic reactivity of slum children by helminthic infection   总被引:10,自引:1,他引:10  
Infection by helminthic parasites can cause the polyclonal stimulation of IgE synthesis, possibly via an enhanced production of interleukin-4 (IL-4), and this has been suggested to influence the allergic reactivity of tropical populations where these parasites are endemic. We evaluated a group of urban slum children in Caracas, Venezuela, with a high prevalence of helminthic infection (70.8%), to establish the relationship between the elevated IgE levels (3696 IU/ml) induced by these parasites and various aspects of the allergic response. Although the absolute levels of IL-4 detected in the sera of these children were low (0.65 ± 0.20 ng/ml), a strong positive correlation (r = 0.78) was found between these and serum IgE. The cutaneous immediate hypersensitivity reactivity to extracts of common environmental allergens was relatively low (17.5% to house dust), although that to Ascaris extract was moderately high (49.4%). Significant inverse correlations were found between total IgE levels and the different skin test reaction diameters, including Ascaris. The positivity of Prausnitz-Kustner passive transfer tests was low in this group (34%), with a strong inverse correlation (r= -0.75) being found between this and total IgE levels. Significant inverse correlations were also found between total IgE levels and specific IgE antibody to environmental allergens, and to Ascaris antigen. We suggest that the polyclonal production of IgE stimulated by helminthic infection can suppress the allergic response to environmental and parasite allergens via both mast cell saturation and inhibition of specific IgE production.  相似文献   
89.
Summary. There are limited data on the prognostic role of biomarkers in anticoagulated patients with atrial fibrillation (AF). We evaluated the prognostic value of high sensitivity TnT (hsTnT) and high‐sensitivity interleukin‐6 (hsIL6) in a large cohort of AF patients taking oral anticoagulant therapy (OAC) as both biomarkers have been associated with adverse cardiovascular events. Methods: We studied 930 patients (51% male; median age 76) with permanent/ paroxysmal AF who were stabilized (for at least 6 months) on OAC (INRs 2.0–3.0). Plasma hsTnT and hsIL6 levels were quantified by electrochemiluminescense immunoassay at baseline. Patients were followed‐up for up to 2 years, and adverse events (thrombotic and vascular events, mortality and major bleeding) were recorded. Results: At follow‐up, 96 patients (3.97%/year) died whilst 107 had an adverse cardiovascular event (3.14%/year). On multivariate analysis, high hsTnT and high hsIL6 remained significantly associated with prognosis even after adjusting for CHADS2 score: HR 2.21 (1.46–3.35, P < 0.001) for high hsTnT and 1.97 (1.29–3.02, P = 0.002) for high hsIL6, for adverse cardiovascular events. For all‐cause mortality, the HRs were 1.79 (1.13–2.83, P = 0.013) and 2.48 (1.60–3.85, P < 0.001), respectively. The integrated discrimination index (IDI) values of clinical scores (CHADS2 and CHA2DS2‐VASc) were improved by the addition of hsTnT and/or hsIL6 (all P < 0.05). Conclusion: In a large ‘real world’ cohort of anticoagulated AF patients, both hsTnT and hsIL6 levels provided prognostic information that was complementary to clinical risk scores for prediction of long‐term cardiovascular events and death, suggesting that these biomarkers may potentially be used to refine clinical risk stratification in AF.  相似文献   
90.
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