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91.
CD Forbes MD FRCP ESPS- Collaborators 《International journal of clinical practice》1997,51(4):205-208
In 1988, an optimal antiplatelet regimen for secondary stroke prevention remained to be defined. We undertook a randomised, placebo-controlled, double-blind trial to investigate the safety and efficacy of low-dose acetylsalicylic acid (ASA), modified-release dipyridamole, and the two agents in combination. Patients with prior stroke or transient ischaemic attack (TIA) were randomised to treatment with ASA alone (50 mg daily), modified-release dipyridamole alone (400 mg daily), the two agents in a combined formulation, or placebo. Primary endpoints were stroke, death, and stroke or death. TIA and other vascular events were secondary endpoints. Patients were followed on treatment for two years. We concluded that dipyridamole, in a modified-release form, at a dose of 200 mg b.d. and ASA 25 mg b.d., have been shown to be equally effective in the secondary prevention of ischaemic stroke and TIA; that when co-prescribed, the protective effects are additive, the combination being significantly more effective than each agent prescribed singly; and that low-dose ASA does not eliminate the propensity for induced bleeding. 相似文献
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93.
Coronary artery bypass graft surgery remains the main treatment modality for multivessel coronary artery disease and has consistently been demonstrated to have significantly lower rates of major adverse cardiac and cerebrovascular events in comparison to percutaneous coronary intervention. In this article we will explore the advances over time and the recent refinements in the techniques of surgical revascularization and how these contribute to the superior outcome profile associated with coronary artery bypass graft surgery. These include the current outcome status of coronary artery bypass grafting; the major landmark trials, registries and meta-analyses comparing coronary artery bypass grafting and percutaneous coronary intervention; the developments in coronary artery disease lesion classification; the techniques for the physiological assessment of coronary artery lesions; bypass grafting using arterial conduits; the role of off-pump coronary artery surgery; the outcomes of reoperative surgery; hybrid techniques for coronary revascularization; minimally invasive coronary artery surgery and finally robotic surgery. 相似文献
94.
Oliver J. Warren Sophie Wallace Katie L. De Wit Charles Vincent Ara W. Darzi Thanos Athanasiou 《Artificial organs》2010,34(3):200-205
In an attempt to reduce the negative sequelae of cardiopulmonary bypass (CPB), a variety of new technologies have been created. This study investigates variations in the application of these technologies throughout Great Britain and Ireland (GB & I). All perfusion departments within GB & I were surveyed about equipment and technologies used in CPB. Eighty‐five percent of units use a standard arterial line filter in all cases. Forty percent of units occasionally use leukocyte‐depleting filters in various sites within the circuit. Sixteen percent always use some element of heparin‐bonded circuit, but 62% never use them. Twenty‐five percent use solely rotary pumps, 18% use solely centrifugal pumps, and 56% use both. Finally, 20% are now using minimal extracorporeal circulation in certain clinical scenarios. These decisions are most frequently affected by clinician preference and cost. This survey has highlighted significant variation in the utilization of various technologies used in CPB. While some variation between centers is to be expected, as innovative technologies are adopted at varying rates, surveys such as this are useful for alerting clinicians to gaps between evidence‐based knowledge and clinical practice. 相似文献
95.
Warren OJ Leff DR Athanasiou T Kennard C Darzi A 《The Journal of surgical research》2009,152(1):167-172
Neurocognitive enhancement is a rapidly expanding scientific field. The vast ethical implications of this developing field for surgical practice have yet to be considered within the literature. This article outlines the reasons surgeons may, in the near future, consider using neurocognitive enhancement and addresses the resulting significant ethical implications of this. We do not seek to support or denounce the potential role of neurocognitive enhancement in surgeons, but to stimulate a debate, which, with ever-increasing levels of stimulant use in schools and colleges, and with a pharmaceutical industry driving the creation of new neuroactive products, has now become a necessity. 相似文献
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Kokkinos C Athanasiou T Rao C Constantinidis V Poullis C Smith A Ridgway M Tekkis PP Darzi A 《Heart, lung & circulation》2007,16(2):93-102
OBJECTIVE: Previous cardiac operation has traditionally been considered as a potential risk factor for patients undergoing heart transplantation. This study aimed to evaluate the outcome of patients undergoing heart transplantation as a second cardiac procedure and compare it with primary heart transplantation, using meta-analytical methodology. METHODS: A literature search was undertaken to identify relevant comparative studies. Outcomes of interest were classified into four categories: (a) intra-operative times; (b) post-operative outcomes; (c) resources; (d) actuarial outcomes. RESULTS: Seven studies matched the selection criteria, reporting on 1004 patients. Six hundred and twenty-three had transplantation as primary operation and 381 as re-operation. The 1-year, 2-year, and 5-year mortality were similar for the two groups (HR=0.85, p=0.54; HR=0.97, p=0.88; and HR=1.04, p=0.92, respectively). Total operative, cold-ischaemic, by-pass, and cross-clamp times were significantly longer for the re-operation group by 59.44 (p<0.001), 14.62 (p=0.05), 25.24 (p<0.001), and 7.93 (p<0.001)min, respectively. Both ICU and hospital stay were longer for the re-operation group but only the former was statistically significant (WMD=1.37; p=0.02). Post-operative complications were similar, except re-exploration rate and blood transfusion requirement, which were higher in the re-operation group (OR=3.51; p<0.001 and WMD=2.21; p<0.001, respectively). CONCLUSIONS: Heart transplantation following previous cardiac operation is technically demanding requiring longer operative times compared to primary heart transplantation. It does not, however, add a significant risk to the survival of the patient, and associated morbidity is not significantly compromised. 相似文献
98.
Martini F D'Offizi G Girardi E Vitale A Cimini E Mollicone B Vlassi C Aiuti F;Other Members of Italian CD Quality Control Network 《AIDS research and human retroviruses》2007,23(6):777-781
We report the results of an external quality control program, including 17 Italian centers involved in the care of patients infected by HIV, to evaluate CD4 T cell count proficiency and reproducibility. The centers received two commercial stabilized blood preparations, one with "normal" and one with "low" CD4 T cell content. The centers were asked to process the samples two times, 1 week apart, with the same procedure used for samples from HIV patients. Most centers showed a good performance of CD4 frequency and absolute count determinations. In particular, the "low" sample was correctly analyzed by all centers; only two underestimated the "normal" sample CD4 frequency, and only one underestimated the CD4 absolute count by >100 CD4 cells/microl. Overall, our data suggest that most Italian laboratories provide reliable and reproducible results in evaluating CD4 T cells in HIV(+) samples. 相似文献
99.
Jones CM Athanasiou T Dunne N Kirby J Aziz O Haq A Rao C Constantinides V Purkayastha S Darzi A 《The Annals of thoracic surgery》2007,83(1):341-348
Multi-detector computed tomography (MDCT) has become an alternative to coronary angiography in diagnosis of graft occlusion and stenosis after coronary artery bypass. A literature search was performed for studies comparing angiography to 8-slice, 16-slice, and 64-slice MDCT in the assessment of coronary grafts. In assessing occlusion, 14 studies produced pooled sensitivity of 97.6%, specificity of 98.5%, diagnostic odds ratio of 934.2, area under the curve of 0.996, and Q* of 0.977. Ninety-six percent of all grafts were visualized for occlusion assessment. Beta blockers, symptomatic status, and postoperative period did not significantly affect diagnostic performance. Stenosis assessment produced sensitivity of 88.7% and specificity of 97.4%. Eighty-eight percent of patent grafts could be assessed for stenosis. The diagnostic accuracy of MDCT approaches angiography for diagnosing graft occlusion and stenosis in patients with venous and arterial coronary bypass grafts. Our findings show that cardiac surgeons will need to interpret MDCT images of both native and grafted vessels soon in preparation for primary or re-do coronary bypass grafting procedures. 相似文献
100.