261 research outputs found

    Therapeutic options for patients with chronic refractory angina pectoris

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    In Raman thermometry, several assumptions are made to model the heat conduction and to extract the thermal conductivity of the samples from the measured data. In this work, the heat conduction in bulk and mesa-like samples was investigated by numerical simulation and measured by the temperature-induced Raman shift method, to study the range of applicability of these assumptions. The effects of light penetration depth and finite sample size on the accuracy of the thermal conductivity determination were investigated by comparing the results of the finite element method with the usual analytical approximation for bulk samples. We found that the assumptions used in the analytical model can be applied to extract the thermal conductivity in solids if the following conditions are fulfilled: the ratio of light penetration depth to laser spot radius is smaller than 0.5, the ratio of spot radius to sample thickness is smaller than 0.1, and the ratio of spot radius to sample half width is smaller than 0.01.JJF and CMST acknowledge the Swedish Research Council VR (349-2007-8664 and 2014-5100) and the Linnaeus Center in Advanced Optics and Photonics for financial support. CMST and ECA acknowledge support from the Spanish MINECO and the Catalan AGAUR (FIS2015-70862-P and CSD2010-00044). JJF is especially grateful to Dr. M. Sledzinska and Dr. B Graczykowski for discussions and assistance with the Raman measurements and simulations. JJF thanks Profs. S. Anand and S. Lourdudoss, and Mr. A. Abedin, for providing the bulk and microcrystal samples. ICN2 acknowledges support from the Severo Ochoa Program (MINECO, Grant SEV-2013-0295) and funding from the CERCA Programme/Generalitat de Catalunya.Peer reviewe

    Treatment of resistant Raynaud's phenomenon with single-port thoracoscopic sympathicotomy:One-year follow-up

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    Objective: Follow-up of patients with treatment-resistant Raynaud's phenomenon (RP) one-year after single-port thoracoscopic sympathicotomy (SPTS). Methods: Eight patients (six males, two females, median age of 45 years) with treatment-resistant RP underwent left-sided SPTS at the third rib (R3), unilaterally. Questionnaires were taken, and number and duration of RP attacks were reported over a 2-week period. Perfusion was assessed with a cooling and recovery procedure at baseline and one year after SPTS. Furthermore, laser speckle contrast analysis, pulse wave velocity, heart rate variability and nailfold capillary microscopy were performed. Results: One year after SPTS the duration of the attacks of was reduced with 1.9 h in the left hand versus 0.3 h in the right hand. Furthermore, three aspects of the questionnaire showed a significant improvement (role limitations due to physical health (p = 0.017), pain (p = 0.027) and physical functioning (p = 0.025)). The total area under the curve of the total cooling and recovery procedure of the left hand was larger one year after surgery (101 (75–140) at baseline versus 118 (95–190) one year post-operatively, p = 0.012), implying a better perfusion in the fingers. This was mainly due to the improvement during the recovery phase (21 (1–41) at baseline versus 38 (24–43) one year post-operatively, p = 0.028). Conclusion: One year after unilateral R3 SPTS the benefit with regard to the majority of outcome variables persisted, though some effects seem to attenuate. Long-term effects and long-term follow-up results will be investigated in an on-going study. Clinical trial registration number: NCT02680509

    Spinal cord stimulation in the treatment of refractory angina: systematic review and meta-analysis of randomised controlled trials

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    <p>Abstract</p> <p>Background</p> <p>The aim of this paper was undertake a systematic review and meta-analysis of the use of spinal cord stimulation (SCS) in the management of refractory angina.</p> <p>Methods</p> <p>We searched a number of electronic databases including Medline, Embase and Cochrane Library up to February 2008 to identify randomised controlled trials (RCTs) reporting exercise capacity, ischemic burden, functional class, quality of life, usage of anti-anginal medication, costs and adverse events including mortality. Results were reported both descriptively for each study and using random effects meta-analysis. Given the variety in outcomes reported, some outcome results were pooled as standardised mean differences (SMD) and reported in standard deviation units.</p> <p>Results</p> <p>Seven RCTs were identified in a total of 270 refractory angina patients. The outcomes of SCS were found to be similar when directly compared to coronary artery bypass grafting (CABG) and percutaneous myocardial laser revascularisation (PMR). Compared to a 'no stimulation' control, there was some evidence of improvement in all outcomes following SCS implantation with significant gains observed in pooled exercise capacity (SMD: 0.76, 0.07 to 1.46, <it>p </it>= 0.03) and health-related quality of life (SMD: 0.83, 95% CI: 0.32 to 1.34, <it>p </it>= 0.001). Trials were small and were judged to range considerably in their quality. The healthcare costs of SCS appeared to be lower than CABG at 2-years follow up.</p> <p>Conclusion</p> <p>SCS appears to be an effective and safe treatment option in the management of refractory angina patients and of similar efficacy and safety to PMR, a potential alternative treatment. Further high quality RCT and cost effectiveness evidence is needed before SCS can be accepted as a routine treatment for refractory angina.</p

    Treatment of resistant Raynaud's phenomenon with single-port thoracoscopic sympathicotomy:a novel minimally invasive endoscopic technique

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    OBJECTIVE: To assess the minimally invasive single-port thoracoscopic sympathicotomy feasibility and efficacy in patients with treatment-resistant RP. METHODS: Single-port thoracoscopic sympathicotomy was performed unilaterally on the left side in eight patients with RP (six males, two females, with a median age of 45.2 years). Five patients had primary and three had secondary RP. Perfusion effects in the hands were assessed at baseline and after 1 month by using a cooling and recovery procedure, and by using laser speckle contrast analysis. Number and duration of RP attacks were reported over a 2-week period. RESULTS: Patient satisfaction was 100% after surgery. After surgery, a unilateral improvement in perfusion was observed in the left hand compared with the right hand, with cooling and recovery (P = 0.008) and with laser speckle contrast analysis (P = 0.023). In addition, the number and duration of the attacks in the left hand decreased compared with the right hand (both P = 0.028). No serious adverse events occurred in a follow-up period of at least 10 months. CONCLUSION: Single-port thoracoscopic sympathicotomy is feasible and can be effective in improving hand perfusion in patients with RP. However, long-term efficacy needs to be established. CLINICAL TRIAL REGISTRATION NUMBER: NCT02680509

    The effect of electrical neurostimulation on collateral perfusion during acute coronary occlusion

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    <p>Abstract</p> <p>Background</p> <p>Electrical neurostimulation can be used to treat patients with refractory angina, it reduces angina and ischemia. Previous data have suggested that electrical neurostimulation may alleviate myocardial ischaemia through increased collateral perfusion. We investigated the effect of electrical neurostimulation on functional collateral perfusion, assessed by distal coronary pressure measurement during acute coronary occlusion. We sought to study the effect of electrical neurostimulation on collateral perfusion.</p> <p>Methods</p> <p>Sixty patients with stable angina and significant coronary artery disease planned for elective percutaneous coronary intervention were split in two groups. In all patients two balloon inflations of 60 seconds were performed, the first for balloon dilatation of the lesion (first episode), the second for stent delivery (second episode). The Pw/Pa ratio (wedge pressure/aortic pressure) was measured during both ischaemic episodes. Group 1 received 5 minutes of active neurostimulation before plus 1 minute during the first episode, group 2 received 5 minutes of active neurostimulation before plus 1 minute during the second episode.</p> <p>Results</p> <p>In group 1 the Pw/Pa ratio decreased by 10 ± 22% from 0.20 ± 0.09 to 0.19 ± 0.09 (p = 0.004) when electrical neurostimulation was deactivated. In group 2 the Pw/Pa ratio increased by 9 ± 15% from 0.22 ± 0.09 to 0.24 ± 0.10 (p = 0.001) when electrical neurostimulation was activated.</p> <p>Conclusion</p> <p>Electrical neurostimulation induces a significant improvement in the Pw/Pa ratio during acute coronary occlusion.</p
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