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51.
BACKGROUND AND AIM OF THE STUDY: Although over 20,000 Edwards-Duromedics valves were implanted worldwide between 1982 and May 1988, use of the valve was voluntarily suspended by the manufacturer in May 1988 on the basis of reported leaflet escapes. In 1990, a modified version was introduced to the market, the Edwards-Tekna. The study aim was to evaluate the short-term outcome with this revised valve. METHODS: Between 1994 and 1998, 137 patients (67 males, 70 females; mean age 36.3+/-9.1 years) underwent heart valve replacement with the Edwards-Tekna prosthesis. Among these patients, 72 had isolated mitral valve replacement, 59 isolated aortic valve replacement, and six double-valve replacement. RESULTS: Early hospital mortality was 0.72% (n = 1). Follow up was 95% complete (129/136 patients discharged from hospital). Mean follow up was 24.9+/-10.5 months (range: 2 to 48 months); total follow up was 282.9 patient-years (pt-yr). Actuarial freedom from complications at two-year follow up and linearized incidence (%/pt-yr) of these events were: late mortality 87.8+/-8.5% (1.77%/pt-yr); thromboembolism 89.8+/-4.9% (2.12%/pt-yr); anticoagulation-related bleeding 97.8+/-1.5% (0.71%/pt-yr); prosthetic valve endocarditis 99.1+/-0.9% (0.35%/pt-yr); valve-related mortality 98.2+/-1.2% (0.71%/pt-yr); and valve-related morbidity and mortality 85.0+/-5.0% (4.24%/pt-yr). There was no structural valve failure such as leaflet escape in this series. Clinically significant hemolysis was not encountered (mean postoperative plasma LDH level 345+/-124 IU/l). Preoperatively, 69% of patients were in NYHA classes III/IV; at two years postoperatively 90% of survivors were in classes I/II. CONCLUSION: The Edwards-Tekna mechanical valve prosthesis has shown excellent overall clinical performance in the short term, though long-term data are needed to confirm its durability.  相似文献   
52.
OBJECTIVES: The purpose of our study was to evaluate the significance of polymorphisms in HLA class II genes in coronary artery ectasia (CAE) patients. METHODS AND RESULTS: Twenty-six patients with CAE without associated cardiac defects were enrolled in the study. CAE was defined as luminal dilation of 1.5- to 2.0-fold of normal limits. Ninety-five healthy subjects who were donors for different organ transplantations, were chosen as control group. Physical examination, electrocardiography and chest X-ray were completely normal in these cases. Both the patients and the control group were screened and compared for their HLA class II genotypes. HLA-DR B1*13, DR16, DQ2 and DQ5 genotypes were significantly more frequent in the patient group.When the known risk factors of coronary heart disease were compared in the patients carrying these genotypes with the non-carrying group, no significant differences were encountered. CONCLUSIONS: HLA-DR B1*13, DR16, DQ2 and DQ5 may be associated with the pathogenesis and increase the risk of CAE.  相似文献   
53.
Maternal smoking is considered to be a risk factor for low birth weight. It is hypothesized that alteration in leptin concentration may be associated with reduced fetal growth. In this study, we assess the effect of smoking during pregnancy on maternal and neonatal serum leptin concentrations, and also on breast milk leptin levels. When the infants were brought to routine physical examination at 7 days old, blood samples and breast milk specimens were taken for leptin measurement from mothers who smoked during pregnancy and their newborns. Nonsmoking mothers and their infants were recruited randomly over the same period as a control group. Maternal age, number of pregnancy, weight of the mothers, birth weight, and gestational age of the infants were similar in both groups (p > 0.05). There was no significant difference between groups in maternal serum and breast milk leptin levels (p = 0.14 and p = 0.96, respectively). However, serum leptin levels were found significantly lower in neonates born to smoking mothers compared with infants born to nonsmoking mothers (p = 0.02). Our findings suggest that maternal smoking dose not have an effect on maternal serum and breast milk leptin levels but decreases neonatal serum leptin concentration independent of birth weight.  相似文献   
54.
Hydrogen peroxide is a liquid that functions in mechanical removal of the necrotic tissue via the elimination of tissue debris.In this study, we aimed to evaluate the effectiveness of the use of hydrogen peroxide in necrosectomy treatment of walled-off pancreatic necrosis.Records of 24 patients who were diagnosed with pancreatic necrosis or walled-off pancreatic necrosis and underwent endoscopic necrosectomy (EN) were retrospectively assessed. Patients were divided into 2 groups; hydrogen peroxide used for treatment or not used, and these 2 groups were compared.A total of 24 patients underwent endoscopic intervention for walled-off pancreatic necrosis. Procedural success was comparable between the 2 groups. During the post-procedural follow-up, the duration of the hospital stay, recurrence, and complication rates were found to be similar in both groups. The mean number of the endoscopic interventions was significantly lower in the hydrogen peroxide group (4.2 ± 1.4 vs 6.1 ± 4.2; P = .01).The use of hydrogen peroxide for EN in walled-off pancreatic necrosis patients seems to have similar efficiency and safety. However, it can be said that the use of hydrogen peroxide could reduce the number of endoscopic procedures.  相似文献   
55.
The aim of this study was to evaluate the histopathological and apoptotic changes occurring in the rat ipsilateral and contralateral testes, after experimental spermatic cord torsion, and to explore and the role of poly(ADP‐ribose) polymerase (PARP) cleavage in testicular torsion–detorsion injury. A total of 37 Wistar albino rats were subjected to 720° unilateral spermatic cord torsion for 1, 2 and 4 h, followed by 4‐h reperfusion, or else to a sham operation (control group). Histology of the testicle was evaluated using haematoxylin–eosin (H&E) staining and Johnsen's scoring system. Germ cell apoptosis was evaluated via active caspase‐3 immunostaining, and PARP expression levels were evaluated via Western blotting. The mean Johnsen's tubular biopsy scores (JTBS) of the ipsilateral testicles were lower for all torsion groups than for the controls (P < 0.05), but the JTBS of the contralateral testicles were only lower in the 4‐h torsion group (P < 0.05). The mean apoptosis score (AS) of the ipsilateral and contralateral testicles was significantly higher in the torsion groups than in the sham group. AS increased correlatively with torsion time, in both testicles. The effect of testicular torsion on PARP cleavage was time dependent, with the highest effect observed after 4 h of testicular torsion (P < 0.05). Testicular torsion caused time‐dependent histological changes, apoptosis and increases in PARP cleavage. Our results suggest that testicular torsion–detorsion injury caused cell damage and germ cell apoptosis that apparently involved cleavage of PARP. Increased PARP cleavage could, in turn, lead to enhanced apoptosis.  相似文献   
56.
OBJECTIVES: We sought to determine whether elimination of pulmonary vein (PV) arrhythmogenicity is necessary for the efficacy of left atrial circumferential ablation (LACA) for atrial fibrillation (AF). BACKGROUND: The PVs often provide triggers or drivers of AF. It has been shown that LACA is more effective than PV isolation in eliminating paroxysmal AF. However, it is not clear whether complete PV isolation is necessary for the efficacy of LACA. METHODS: In 60 consecutive patients with paroxysmal (n = 39) or chronic (n = 21) AF (mean age 53 +/- 12 years), LACA to encircle the left- and right-sided PVs, with additional lines in the posterior left atrium and along the mitral isthmus, was performed under the guidance of an electroanatomic navigation system. The PVs were mapped with a decapolar ring catheter before and after LACA. If PV isolation was incomplete, no attempts at complete isolation were made. RESULTS: After LACA, there was incomplete electrical isolation of one or more PVs in 48 (80%) of the 60 patients. The prevalence of PV tachycardias was 82% before and 8% after LACA (p < 0.001). At 11 +/- 1 months of follow-up, 10 (83%) of the 12 patients with complete and 39 (81%) of 48 patients with incomplete PV isolation were free from recurrent AF without antiarrhythmic drug therapy (p = 1.0). A successful outcome was not related to the number of completely isolated PVs per patient (p = 0.6). CONCLUSIONS: Left atrial circumferential ablation modifies the arrhythmogenic substrate within the PVs. Complete electrical isolation of the PVs is not a requirement for a successful outcome after LACA.  相似文献   
57.
Delayed diagnosis of tuberculous arthritis   总被引:2,自引:0,他引:2  
Monoarticular tuberculosis (TB) affecting the knee is rare in all forms of TB (0.1-0.3%). We present the case of a patient with tuberculous arthritis in whom the diagnosis was belated due to a lack of familiarity with the disease; here, we emphasize the difficulties associated with the diagnosing joint TB. A 20-year-old man was referred to our department due to swelling of the right knee and the presence of persistent, mild pain for 4 years. The lack of systemic evidence of this disease, the indolent course of disease, and the presence of non-specific symptoms renders early recognition of this disease difficult. Furthermore, in cases in which a diagnosis cannot be reached simply by culturing the synovial fluid, synovial biopsy cultures should be considered in the diagnostic process, due to the high rate of positivity of such cultures. The diagnosis and treatment of articular TB are both urgent matters; surgical debridement and strict adherence to antituberculous chemotherapy tend to yield a satisfactory functional outcome.  相似文献   
58.
Background A better understanding of the mechanisms of recurrent atrial fibrillation (AF) after radiofrequency ablation of complex, fractionated atrial electrograms (CFAEs) may be helpful for refining AF ablation strategies. Methods and results Electrogram-guided ablation (EGA) was repeated in 30 consecutive patients (mean age = 59 ± 8 years) for recurrent paroxysmal AF, 10 ± 4 months after the first ablation. During the first procedure, CFAEs were targeted without isolating all pulmonary veins (PVs). During repeat ablation, all PVs and the superior vena cava (SVC) were mapped with a circular catheter and the left atrium was mapped for CFAEs. EGA was performed until AF was rendered noninducible or all identified CFAEs were eliminated. During repeat ablation, ≥1 PV tachycardia was found in 83 PVs in 29 of the 30 patients (97%). Among these 83 PVs, 63 (76%) had not been completely isolated previously. During repeat ablation, drivers originating in a PV or PV antrum were identified only after infusion of isoproterenol (20 μg/min) in 12 patients (40%). At 9 ± 4 months of follow-up after the repeat ablation procedure, 21 of the 30 patients (70%) were free from recurrent AF and flutter without antiarrhythmic drugs. Conclusions Recurrence of AF after EGA is usually due to PV tachycardias. Therefore, it may be preferable to systematically map and isolate all PVs during the first procedure. High-dose isoproterenol may be helpful to identify AF drivers.  相似文献   
59.
Objective: The aim of present study was to evaluate the indications and the complications associated with neonatal exchange transfusion (ET) performed for hyperbilirubinemia.

Methods: This study included overall 306 neonates who underwent ET between 2005 and 2012. The demographic characteristics of patients, causes of jaundice and adverse events occurred during or within 1 week after ET were recorded from their medical files. Those newborns that underwent ET were classified as either “otherwise healthy” or “sick” group.

Results: Of the 306 patients who underwent ET, 244 were otherwise healthy and had no medical problems other than jaundice. The remaining 62 patients were classified as sick that had medical problems other than jaundice ranging from mild to severe. The mean gestational age was 37.6?±?2.5 weeks and the mean peak total bilirubin levels was 25.8?±?6.6?mg/dl. The mean age at presentation was 5.4?±?3.8?d for all infants. The most common cause of hyperbilirubinemia was ABO isoimmunization (27.8%). None of newborns died secondary to ET. Three infants had had necrotizing enterocolitis, and also three infants had had acute renal failure. The most common encountered complications of ET procedure were hyperglycemia (56.5%), hypocalcaemia (22.5%) and thrombocytopenia (16%).

Conclusions: Our data showed that ABO isoimmunization was the most common cause of hyperbilirubinemia. Even mortality was not seen, very rare but major gastrointestinal and renal complications were associated with ET. The majority of adverse events associated with ET were laboratory abnormalities mainly hyperglycemia, hypocalcaemia and thrombocytopenia which were asymptomatic and treatable.  相似文献   
60.
Thrombotic microangiopathies (TMAs) are rare, but life-threatening disorders characterized by microangiopathic hemolytic anemia and thrombocytopenia (MAHAT) associated with multiorgan dysfunction as a result of microvascular thrombosis and tissue ischemia. The differentiation of the etiology is of utmost importance as the pathophysiological basis will dictate the choice of appropriate treatment.We retrospectively evaluated 154 (99 females and 55 males) patients who received therapeutic plasma exchange (TPE) due to a presumptive diagnosis of TMA, who had serum ADAMTS13 activity/anti-ADAMTS13 antibody analysis at the time of hospital admission. The median age of the study cohort was 36 (14-84). 67 (43.5%), 32 (20.8%), 27 (17.5%) and 28 (18.2%) patients were diagnosed as thrombotic thrombocytopenic purpura (TTP), infection/complement-associated hemolytic uremic syndrome (IA/CA-HUS), secondary TMA and TMA-not otherwise specified (TMA-NOS), respectively. Patients received a median of 18 (1­75) plasma volume exchanges for 14 (153) days. 81 (52.6%) patients received concomitant steroid therapy with TPE. Treatment responses could be evaluated in 137 patients. 90 patients (65.7%) achieved clinical remission following TPE, while 47 (34.3%) patients had non-responsive disease. 25 (18.2%) non-responsive patients died during follow-up. Our study present real-life data on the distribution and follow-up of patients with TMAs who were referred to therapeutic apheresis centers for the application of TPE.  相似文献   
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