Severe accordion effect: Myocardial ischemia due to wire complication during percutaneous coronary intervention: A case report

A mechanical alteration during manoeuvring of stiff guidewires in tortuous coronary arteries frequently induces vessel wall shortening and coronary psedostenosis, referred as accordion phenomenon. Subtraction of the guidewires normally leads to the entire resolution of the lesions. A case of this transient angiographic finding, during percutaneous coronary intervention in a tortuous right coronary artery, which resulted in a flow limiting effect and myocardial ischemia, is described in the present report. Differential diagnosis from potential procedure complications and interventional methodology issues are discussed, while similar reports are reviewed

Primary Percutaneous Coronary Intervention in Acute ST-Elevation Myocardial Infarction: The Experience of "Evagelismos" General Hospital of Athens

BACKROUND: Primary percutaneous coronary intervention (PCI) has been shown to be a better reperfusion strategy in patients with ST-elevation myocardial infarction (STEMI) compared with thrombolysis, particularly when applied early. The objective of the present study was to report our experience from treating patients presenting to the emergency room of our hospital with STEMI with primary PCI. PATIENTS AND METHODS: The population of the study included 100 patients who presented to our hospital with STEMI and underwent primary PCI over a 12-month period. Patients’ clinical and angiographic data were retrospectively collected and patients were followed up for 9 months. Technical details of the primary PCI, including stent implantation, and use of drug eluting stents, thrombus aspiration catheter, or platelet glycoprotein IIb/ΙΙΙa inhibitors were recorded and correlated to clinical and angiographic patient data. RESULTS: Of 196 patients who presented o the emergency room with STEMI during the study period, 100 (51%) patients (85 men and 15 women) underwent primary PCI. PCI was successful with TIMI 3 flow of the infarct-related coronary artery in 79 (79%) patients. Six (6%) patients died during hospitalization and another 4 (4.3%) patients died during the 9-month follow up period. Twenty one (22%) patients required rehospitalization for acute coronary syndrome, of whom 17 needed a repeat PCI and 4 patients were submitted to coronary artery bypass grafting. Left ventricular ejection fraction (LVEF) was <50% in 54 (54%) patients. In 52 patients primary PCI was performed in less than 4 hours from onset of symptoms. In his cohort, 19 patients were thrombolyzed before arriving to the catheterization laboratory. Antithrombotic therapy with platelet glycoprotein IIb/IIIa inhibitors was used in 48 (48%) patients. Univariate analysis showed that the odds of achieving TIMI 3 flow were higher after using IIb/ΙΙΙa inhibitors (odds ratio-OR 6.4) or if the LVEF ≥50% (vs LVEF < 50%) at the beginning of the PCI (OR 6.4). If the time from the onset of symptoms to PCI was >4 hours, the odds of achieving TIMI 3 flow were reduced by 23.4% compared to time from symptoms to PCI <4 hours. The presence of TIMI 3 flow of the infarct-related artery reduced the odds of death by 10.2% compared to the absence of TIMI 3 flow of the infarct-related coronary artery. CONCLUSION: Our results are in keeping with those published by other groups performing primary PCI. We demonstrated the importance of time interval from onset of symptoms until PCI is started. We found that the use of GP IIb/IIIa inhibitors was beneficial and emphasized the predictive value of LVEF >50% and the importance of achieving TIMI 3 flow in the IRA at the end of the procedure

Content Transformation Techniques

this paper: the way of migrating data from device to device without damaging the integrity of the data and without distracting the use

Exploring Term Document Matrices From Matrix Models in Text Mining

We explore a matrix-space model, that is a natural extension to the vector space model for Information Retrieval. Each document can be represented by a matrix that is based on document extracts (e.g. sentences, paragraphs, sections). We focus on the performance of this model for the specific case in which documents are originally represented as term-by-sentence matrices. We use the singular value decomposition to approximate the term-by-sentence matrices and assemble these results to form the pseudo-"term-document" matrix that forms the basis of a text mining method alternative to traditional VSM and LSI. We investigate the singular values of this matrix and provide experimental evidence suggesting that the method can be particularly effective in terms of accuracy for text collections with multi-topic documents, such as web pages with news

Personalized news categorization through scalable text classification

Abstract. Existing news portals on the WWW aim to provide users with numerous articles that are categorized into specific topics. Such a categorization procedure improves presentation of the information to the end-user. We further improve usability of these systems by presenting the architecture of a personalized news classification system that exploits user’s awareness of a topic in order to classify the articles in a ‘per-user ’ manner. The system’s classification procedure bases upon a new text analysis and classification technique that represents documents using the vector space representation of their sentences. Traditional ‘term-to-documents ’ matrix is replaced by a ‘term-to-sentences ’ matrix that permits capturing more topic concepts of every document.