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Carpentier-Edwards Magna ease versus Magna valves: a comparison of in-vitro valve hydrodynamic performance.
No full textBACKGROUND AND AIM OF THE STUDY:
Previous studies have shown that the Carpentier-Edwards Magna (CEM) valve is an excellent bioprosthesis in terms of its systolic performance; indeed, it has been described as 'a stented valve with stentless performance'. However, valve performance is not only a matter of gradients; it is also necessary to evaluate the diastolic-phase performance. Previous in-vitro studies have shown that the CEM has an excessive total regurgitant volume. Hence, the study aim was to compare the hydrodynamics of the CEM, with the newly evolved version of this valve, the CEM Ease (CEME).
METHODS:
The CEM and CEME valves (both 21 mm) were tested in the aortic chamber (23 mm diameter) of the Sheffield pulse duplicator. The tests were carried out at increasing pulse rates (PR; 70-100 beats/min), and at each pulse rate the valve was tested at different stroke volumes (SVs; 45-65 ml). The forward-flow pressure drop, closing leakage volumes and effective orifice area (EOA) were recorded.
RESULTS:
The CEM and CEME valves showed a comparable systolic-phase performance, there being no significant differences in terms of transvalvular gradient, EOA and stroke work loss, regardless of the PR and SV. In fact, the new CEME exhibited a significantly improved diastolic performance, with the total regurgitant volume being significantly lower, due especially to a reduced leakage volume and, to a lesser extent, a reduced closing volume.
CONCLUSION:
The study results indicated that the new CEME valve would maintain the excellent systolic performance of the previous CEM model, but with a significantly improved diastolic performance
Descending aorta-to-coronary artery bypass graft imaging by means of multislice computed tomography.
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Von Willebrand factor multimers and the relaxation response: A one-year study
Get PDFBackground and aim: Mental stress represents a pivotal factor in cardiovascular diseases. The mechanism by which stress produces its deleterious ischemic effects is still under study but some of the most explored pathways are inflammation, endothelial function and balancing of the thrombotic state. In this scenario, von Willebrand factor (vWF) is a plasma glycoprotein best known for its crucial hemostatic role, also acting as key regulatory element of inflammation, being released by the activated vascular endothelium. Antistress techniques seem to be able to slow down inflammation. As we have recently verified how the practice of the Relaxation Response (RR), which counteracts psychological stress, causes favorable changes in some inflammatory genes’ expressions, neurotransmitters, hormones, cytokines and inflammatory circulating microRNAs with coronary endothelial function improvement, we aimed to verify a possible change even in serum levels of vWF. Experimental procedure: We measured vWF multimers and the total protein carbonyl contents in the sera of 90 patients with ischemic heart disease (and 30 healthy controls) immediately before and after an RR session, three times (baseline, 6 months, 12 months), during a one-year follow- up study. Results: According to our data, large vWF multimers decrease during the RR, as does the plasma total carbonyl content. Conclusion: vWF levels seem to vary rapidly between anti-inflammatory and antithrombotic behaviors dependent on psychological activity, leading to relaxation and also possibly changes in its quaternary structure
Carpentier-Edwards Magna Ease versus Magna: Comparison of in vitro Valve Hydrodynamic Performance
No full textInflammation and coronary microvascular dysfunction in autoimmune rheumatic diseases
Get PDFAutoimmune rheumatic diseases (ARDs) form a heterogeneous group of disorders that include systemic lupus erythematosus (SLE), systemic sclerosis (SSc), rheumatoid arthritis (RA), idiopathic inflammatory myopathies (IIMs), and systemic vasculitis. Coronary microvascular dysfunction (CMD) is quite common in patients with ARDs and is linked to increased cardiovascular morbidity and mortality. Inflammation plays a crucial role in the pathogenesis of both accelerated atherosclerosis and CMD in ARDs, especially in patients affected by SLE and RA. In this regard, some studies have highlighted the efficacy of immunosuppressants and/or biologics in restoring CMD in these patients. By contrast, the role of inflammation in the pathogenesis of CMD-SSc appears to be much less relevant compared to endothelial dysfunction and microvascular ischemia, with calcium-channel blockers providing some benefits. Few studies have endeavored to assess the occurrence of CMD in IIMs and systemic vasculitis, thus warranting further investigations. The present review summarizes the current evidence on the occurrence of CMD in ARDs, focusing on the role of inflammation and possible therapeutic approaches
Toward a Unified View of Cognitive and Biochemical Activity: Meditation and Linguistic Self-Reconstructing May Lead to Inflammation and Oxidative Stress Improvement
Get PDFGoing Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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