77 research outputs found
Fully Automated Lipid Pool Detection Using Near Infrared Spectroscopy
Background. Detecting and identifying vulnerable plaque, which is prone to rupture, is still a challenge for cardiologist. Such lipid core-containing plaque is still not identifiable by everyday angiography, thus triggering the need to develop a new tool where NIRS-IVUS can visualize plaque characterization in terms of its chemical and morphologic characteristic. The new tool can lead to the development of new methods of interpreting the newly obtained data. In this study, the algorithm to fully automated lipid pool detection on NIRS images is proposed. Method. Designed algorithm is divided into four stages: preprocessing (image enhancement), segmentation of artifacts, detection of lipid areas, and calculation of Lipid Core Burden Index. Results. A total of 31 NIRS chemograms were analyzed by two methods. The metrics, total LCBI, maximal LCBI in 4 mm blocks, and maximal LCBI in 2 mm blocks, were calculated to compare presented algorithm with commercial available system. Both intraclass correlation (ICC) and Bland-Altman plots showed good agreement and correlation between used methods. Conclusions. Proposed algorithm is fully automated lipid pool detection on near infrared spectroscopy images. It is a tool developed for offline data analysis, which could be easily augmented for newer functions and projects
Alpha-2-antiplasmin Arg407Lys polymorphism and cryptogenic ischemic cerebrovascular events: Association with neurological deficit
Objective
Genetic background of cryptogenic ischemic stroke (IS) and transient ischemic attack (TIA) remains uncertain. Alpha-2-antiplasmin (α2AP) Arg407Lys polymorphism has been shown to be less common in patients with abdominal aortic aneurysm (AAA) compared with healthy controls. We investigated associations of α2AP Arg407Lys polymorphism with cryptogenic IS and TIA.
Methods
We studied 165 consecutive Caucasian patients who experienced cryptogenic IS (n=123) or TIA (n=42). Neurological outcomes were assessed using the modified Rankin Scale (mRS) in the acute phase of cerebral ischemia and 8 (6–12) months after the index episode. Patients were genotyped for α2AP Arg407Lys polymorphism (rs1057335) using real time PCR technique.
Results
The allele frequency of Arg407Lys polymorphism was: 0.82/0.18. The 407Lys allele was more frequent in TIA patients compared to the IS group (0.29 vs. 0.14, p=0.003). In the whole group, as well as in IS and TIA patients analyzed separately, possession of the 407Lys allele was associated with excellent outcome (mRS 0–1) during follow-up (p<0.05) but not in the acute phase of ischemic events both in thrombolyzed and nonthrombolyzed IS patients.
The multivariate logistic regression model showed that the excellent outcome (mRS 0–1) assessed after 8 (6–12) months since the index cerebral ischemia was predicted by the occurrence of Lys407 allele (OR 6.18, 95% CI, 2.01–18.98, p=0.001).
Conclusion
The presence of 407Lys allele is associated with better prognosis in cryptogenic cerebrovascular events. Our findings suggest that the α2AP Arg407Lys polymorphism could be involved in the pathogenesis of cerebral ischemia and its outcomes
A Software Platform for Research on Auction Mechanisms, Journal of Telecommunications and Information Technology, 2011, nr 3
The platform for research on auction mechanisms is a distributed simulation framework providing means to carry out research on resource allocation efficiency mechanisms and user strategies. Both kinds of algorithms examined are completely user-defined. Interaction of algorithms is recorded and pre-defined measures for the final resource allocation are calculated. Underlying database design provides for efficient results lookup and comparison across different experiments, thus enabling research groupwork. A recognised, open and flexible information model is employed for experiment descriptions
Fully Automated Lumen Segmentation Method for Intracoronary Optical Coherence Tomography.
BACKGROUND: Optical coherence tomography (OCT) is an innovative imaging technique that generates high-resolution intracoronary images. In the last few years, the need for more precise analysis regarding coronary artery disease to achieve optimal treatment has made intravascular imaging an area of primary importance in interventional cardiology. One of the main challenges in OCT image analysis is the accurate detection of lumen which is significant for the further prognosis. METHOD: In this research, we present a new approach to the segmentation of lumen in OCT images. The proposed work is focused on designing an efficient automatic algorithm containing the following steps: preprocessing (artifacts removal: speckle noise, circular rings, and guide wire), conversion between polar and Cartesian coordinates, and segmentation algorithm. RESULTS: The implemented method was tasted on 667 OCT frames. The lumen border was extracted with a high correlation compared to the ground truth: 0.97 ICC (0.97-0.98). CONCLUSIONS: Proposed algorithm allows for fully automated lumen segmentation on optical coherence tomography images. This tool may be applied to automated quantitative lumen analysis.Peer Reviewe
Aspiration thrombectomy in patients with acute myocardial infarction-5-year analysis based on a large national registry (ORPKI)
Three-dimensional reconstruction of conventional catheter angiography-identified coronary artery aneurysms and ectasias
Reimbursement Status and Recommendations Related to Orphan Drugs in European Countries
Objective: To review the reimbursement recommendations issued by selected European health technology assessment agencies for orphan drugs and the reimbursement status of these drugs; to assess the relationship between the type of recommendation and reimbursement status.
Methods: The list of orphan drugs to be included in the analysis was obtained from the European Medicines Agency and Orphanet. Seven European states were included in the analysis: Belgium, England, France, Germany, Poland, Scotland, and Spain. For all identified orphan drugs, relevant data on the reimbursement status and type of recommendation were collected for each country. The relationship between the type of recommendation and reimbursement status was evaluated separately for each considered country, using Cohen’s kappa coefficient for the measurement of agreement; sub-analyses for oncology and metabolic drugs were performed.
Results: Most reimbursement recommendations for orphan drugs were positive (71%), while approximately 17% were negative and almost 13% were conditional. The highest percentage of positive reimbursement recommendations was observed in Spain (97%) and France (95%) and the highest percentage of negative reimbursement recommendations was revealed for Poland (49%). On average, 65% of the 163 analyzed orphan drugs were reimbursed from public funds. The highest number of reimbursed orphan drugs was observed in Germany (n = 148), while the lowest, in Poland (n = 41). Considering all analyzed drugs, the highest agreement between recommendations and reimbursement status was observed for Spain (value of 1), and the lowest, for Germany (κ = -0.03).
Conclusions: On average, more than 60% of identified orphan drugs were reimbursed from public funds in the included countries, and the majority of reimbursement recommendations were found to be positive. The agreement between reimbursement recommendations and reimbursement status differed between the countries, but overall, it did not show any patterns, as it ranged from -0.03 to 1 (κ coefficient)
Association between the mortality rate and operator volume in patients undergoing emergency or elective percutaneous coronary interventions
Background: Previous studies have suggested that low operator and institutional volume may be associated with an increased risk of adverse events in patients undergoing percutaneous coronary intervention (PCI).
Aims: The aim of the study was to assess the relationship between operator volume and procedure related mortality in the emergent and elective settings.
Methods: Data were obtained from a national registry of PCIs, maintained in cooperation with the Association of Cardiovascular Interventions of the Polish Cardiac Society. Registry data for the period from January 2014 to December 2017 were collected. During the study, there were 162 active catheterization laboratories, in which a total of 456 732 PCIs were performed.
Results: The median number of PCIs performed in a single laboratory was 2643.5 (interquartile range [IQR], 1875–3598.5) over 4 years. The median number of PCIs performed by a single operator was 557 (IQR, 276.25–860.5) per year. We did not confirm a significant relationship between the operator volume and mortality in the overall group of patients treated with emergency and elective PCI. However, we noted a lower mortality rate for high‑volume operators (odds ratio [OR], 0.79; 95% CI, 0.63–0.99; P = 0.04). When the operator volume was assessed as a continuous variable, there was a trend toward significance (OR, 0.94; 95% CI; 0.88–1.0007; P = 0.052) in patients treated with emergency PCI.
Conclusions: High operator volume was associated with a lower periprocedural mortality rate than low operator volume in patients undergoing PCI due to acute coronary syndromes
Long-term prognostic significance of high-sensitive troponin I increase during hospital stay in patients with acute myocardial infarction and non-obstructive coronary arteries
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