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Objectives : To reduce risks, discomfort, cost, and operative time for percutaneous patent foramen ovale (PFO) closure, we propose to perform this procedure under transesophageal echo‐guidance using a 10 Fr. catheter introduced through nasal way (TEENW). Background : Transesophageal or intracardiac echocardiography is commonly used to guide percutaneous PFO closure. Sedation needed quite frequently during transesophageal echocardiography, increased patients' discomfort, procedure prolongation, costs, use of both femoral veins, and additional intracardiac manipulations are the main limitations of standard techniques. Methods : We enrolled 20 consecutive patients with a history of cerebral ischemia and PFO with right‐to‐left shunt. In 15 patients Amplatzer® PFO occluder was used, whereas in five patients with longer PFO tunnel (>10 mm) Cardia Intrasept® was selected. Without sedation, a multifrequency monoplane probe, developed for intracardiac echocardiography, was introduced into the nostril and advanced forward the esophagus. Then under echo guidance, the closing device was presented, opened and released. Results : Procedure lasted for an average of 33.3 min, and no complications were seen. At procedure's completion, six patients showed persistence of reduced shunt during Valsalva manoeuvre. At six‐month follow‐up, shunts disappeared in all patients. Conclusion : TEENW is safe and well tolerated, and images' quality is high enough to deserve widespread adoption of this technique for PFO closure. © 2008 Wiley‐Liss, Inc.  相似文献   
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Background: Fractional flow reserve (FFR) has become a useful tool in the assessment of physiological significance of coronary artery stenosis (CAS), and Adenosine (ADE) is associated with a high incidence of transient side effects. Sodium nitroprusside (NPS) has been proposed as an alternative vasodilator agent. A meta-analysis of studies comparing ADE and NPS for FFR assessment in the same coronary lesions was performed.

Methods: Authors searched for articles comparing NPS and ADE for FFR assessment in intermediate coronary lesions published through January 2018. The following keywords were used: ‘fractional flow reserve’ AND ‘nitroprusside’. Data were summarized using weighted mean differences for paired data.

Results: Seven studies were identified comprising 342 patients and 401 lesions. Four studies evaluated intravenous ADE and 3 studies intracoronary ADE administration. Weighted means FFR values obtained with ADE and NPS were 0.8411 and 0.8445, respectively (weighted mean difference: 0.00, 95% confidence interval (CI) ?0.01 to 0.01, p = 0,548). Adverse events were significantly reduced with IC NPS (RR = 0.08, 95%CI 0.02–0.30, P < 0.0001).

Conclusions: NPS produces similar FFR measurements compared to ADE with a significant reduction in adverse effects. These results may support its use as a suitable alternative to ADE for FFR assessment.  相似文献   
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AIMS: The aims of the present study were: (a) to demonstrate whether quantitative myocardial contrast echocardiography can detect the increase in coronary flow induced by dipyridamole infusion vasodilation through the myocardial opacification due to the transit of microbubbles, both at rest and after dipyridamole induced vasodilation; (b) to explore the coronary microcirculatory function before and after dipyridamole in two different models: asymptomatic and relatively young hypertensive patients with a mild degree of left ventricular hypertrophy, and healthy controls. METHODS AND RESULTS: Two groups of strictly age-matched males were studied (case-control study): 10, relatively young and asymptomatic essential hypertensive patients with a mild degree of left ventricular hypertrophy with a normal left ventricular function, and 10 healthy controls. The main findings were: the microbubbles' appearance area was significantly lower in hypertensive patients than in controls (P<0.05) because of a significantly lower time to peak. The peak intensity at rest was higher in hypertensives than in controls (P<0.05); but the per cent increase after vasodilatory stimulus was significantly higher in controls (+71% in controls vs +31% in hypertensives; P<0.05). The microbubbles' disappearance area was comparable in both groups at rest; the per cent increase of this parameter after dipyridamole was significantly higher in controls (+124%) than in hypertensives (+90%) (P<0.05). The results achieved in this study documented that the coronary microcirculation in hypertensive patients presenting a mild degree of left ventricular hypertrophy, explored with quantitative myocardial contrast echocardiography, showed a different behaviour in comparison with controls, in the vasodilatory response to dipyridamole. CONCLUSION: The coronary microcirculation in hypertensives showed a reduced vasodilation capacity of the resistance arterioles under dipyridamole induced vasodilatation, and a possible impairment of the endothelium dependent vasodilation. This happened despite an increase in the left ventricular mass, where the relation between capillary bed distribution and hypertrophied myocardium (rarefaction phenomenon) is not completely respected.  相似文献   
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Summary. The molecular defects causing CRM+ factor VII deficiency were investigated in seven unrelated subjects and several members of their families.
Four missense mutations located in the catalytic domain of factor VII were found. The previously reported 304ArgGln substitution was present in the homozygous and heterozygous forms, with different polymorphic haplotypes, thus demonstrating that it is recurrent and frequent in the Italian population. The 310Cys Phe substitution was found in the homozygous form and in the compound heterozygous condition with the nonsense mutation 356Trpstop. Two missense mutations, 298MetIle and 342GlyArg, were found in the homozygous and in the heterozygous condition respectively.
Molecular heterogeneity was further increased by finding of the 353ArgGln polymorphism in the doubly heterozygous condition with the 304 and 342 mutations.
Plausible explanations for loss of FVII function were found by inspecting a model of the serine protease domain of factor VIIa. Inefficient activation of the catalytic site is predicted for 298MetIle. 342GlyArg would directly distort the geometry of the 'oxyanion hole'preventing formation of a substrate enzyme intermediate. 310Cyshe is predicted to have an adverse effect on tissue factor interaction. These mutations point to important regions of the factor VII molecule.  相似文献   
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BACKGROUND: Treatment of patients with suspected deep vein thrombosis (DVT) or pulmonary embolism (PE) is problematic if diagnostic imaging is not immediately available. Pretest clinical probability (PCP) and D-dimer assessment can be used to identify patients for whom empirical protective anticoagulation is indicated. To evaluate whether PCP and D-dimer assessment, together with the use of low-molecular-weight heparins (LMWHs), allow objective appraisal of DVT and PE to be deferred for up to 72 hours, patients with suspected DVT and PE were prospectively examined. METHODS: Patients identified with a high PCP or a moderate PCP with positive D-dimer test results received a protective full-dose treatment of LMWH; the remaining patients were discharged without anticoagulant administration. However, all patients were scheduled to undergo objective tests for DVT or PE within 72 hours. Standard antithrombotic therapy was administered when deferred diagnostic tests confirmed venous thromboembolism. RESULTS: In total, 409 consecutive patients with suspected DVT and 124 with suspected PE were included in this study. A total of 23.8% (95% confidence interval [CI], 20.3%-27.3%) of patients had confirmed venous thromboembolism. At the short-term follow-up (72 hours), only a single thromboembolic event (0.2%; upper 95% CI, 0.6%) had occurred, whereas at the 3-month follow-up, 5 events (1.2%; 95% CI, 0.2%-2.1%) had occurred in patients in whom diagnosis of DVT or PE had previously been ruled out. None of the patients had major bleeding events. Ninety percent of patients were treated as outpatients. CONCLUSION: Our study demonstrates that this approach allows the safe deferral of diagnostic procedures for DVT and PE for up to 72 hours.  相似文献   
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