Hotline sessions of the 28th European Congress of Cardiology/World Congress of Cardiology 2006.

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How to react to high platelet reactivity?

Given a grid of cells, each having a value indicating its cost per unit area, a variant of the least-cost path problem is to find a corridor of a specified width connecting two termini such that its cost-weighted area is minimized. A computationally efficient method exists for finding such corridors, but as is the case with conventional raster-based least-cost paths, their incremental orientations are limited to a fixed number of (typically eight orthogonal and diagonal) directions, and therefore, regardless of the grid resolution, they tend to deviate from those conceivable on the Euclidean plane. Additionally, these methods are limited to problems found on two-dimensional grids and ignore the ever-increasing availability and necessity of three-dimensional raster based geographic data. This thesis attempts to address the problems highlighted above by designing and testing least-cost corridor algorithms. First a method is proposed for solving the two-dimensional raster-based least-cost corridor problem with reduced distortion by adapting a distortion reduction technique originally designed for least-cost paths and applying it to an efficient but distortionprone least-cost corridor algorithm. The proposed method for distortion reduction is, in theory, guaranteed to generate no less accurate solutions than the existing one in polynomial time and, in practice, expected to generate more accurate solutions, as demonstrated experimentally using synthetic and real-world data. A corridor is then modeled on a threedimensional grid of cost-weighted cubic cells or voxels as a sequence of sets of voxels, called ‘neighborhoods,’ that are arranged in a 26-hedoral form, design a heuristic method to find a sequence of such neighborhoods that sweeps the minimum cost-weighted volume, and test its performance with computer-generated random data. Results show that the method finds a low-cost, if not least-cost, corridor with a specified width in a threedimensional cost grid and has a reasonable efficiency as its complexity is O(n2) where n is the number of voxels in the input cost grid and is independent of corridor width. A major drawback is that the corridor found may self-intersect, which is often not only an undesirable quality but makes the estimation of its cost-weighted volume inaccurate.Med tanke på ett rutnät av celler, som vart och ett har ett värde som indikerar dess kostnad per areaenhet, är en variant av det billigaste banproblemet att hitta en korridor med en specificerad bredd som förbinder två terminaler så att dess kostnadsviktade område minimeras. Det finns en beräkningseffektiv metod för att hitta sådana korridorer, men som är fallet med konventionella rasterbaserade lägsta kostnadsspår är deras inkrementella orienteringar begränsade till ett fast antal (vanligtvis åtta ortogonala och diagonala) riktningar, och därför, oavsett nätupplösning tenderar de att avvika från de tänkbara på det euklidiska planet. Dessutom är dessa metoder begränsade till problem som finns i tvådimensionella nät och ignorerar den ständigt ökande tillgängligheten och nödvändigheten av tredimensionell rasterbaserad geografisk data. Denna avhandling försöker ta itu med problemen som belyses ovan genom att utforma och testa korridoralgoritmer till lägsta kostnad. Först föreslås en metod för att lösa det tvådimensionella rasterbaserade problemet med billigaste korridorer med minskad förvrängning genom att anpassa en distorsionsminskningsteknik som ursprungligen utformades för billigaste vägar och tillämpa den på en effektiv men distorsionsbenägen billigaste korridoralgoritm. Den föreslagna metoden för distorsionsminskning är i teorin garanterad att generera inte mindre exakta lösningar än den befintliga i polynomtid och i praktiken förväntas generera mer exakta lösningar, vilket demonstreras experimentellt med syntetiska och verkliga data. En korridor modelleras sedan på ett tredimensionellt rutnät av kostnadsvägda kubikceller eller voxels som en sekvens av uppsättningar av voxels, kallade "stadsdelar", som är ordnade i en 26-hedoral form, designar en heuristisk metod för att hitta en sekvens av sådana stadsdelar som sveper den lägsta kostnadsviktade volymen och testar dess prestanda med datorgenererade slumpmässiga data. Resultaten visar att metoden hittar en låg kostnad, om inte minst kostnad, korridor med en specificerad bredd i ett tredimensionellt kostnadsnät och har en rimlig effektivitet eftersom dess komplexitet är O (n2) där n är antalet voxlar i ingångskostnadsnätet och är oberoende av korridorbredd En stor nackdel är att korridoren som hittas kan korsa sig själv, vilket ofta inte bara är en oönskad kvalitet utan gör uppskattningen av dess kostnadsviktade volym felaktig.QC 20210309</p

Adjunctive treatment in patients treated with thrombolytic therapy

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Antiplatelet treatment for coronary heart disease

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Gender differences in partners of patients with COPD and their perceptions about the patients

Contains fulltext : 170329.pdf (publisher's version ) (Open Access)BACKGROUND/OBJECTIVES: Chronic obstructive pulmonary disease (COPD) not only affects patients but also their partners. Gender-related differences in patients with COPD are known, for instance regarding symptoms and quality of life. Yet, research regarding gender differences in partners of patients with COPD has been conducted to a lesser extent, and most research focused on female partners. We aimed to investigate differences between male and female partners of patients with COPD regarding their own characteristics and their perceptions of patients' characteristics. DESIGN: Cross-sectional study. SETTING: Four hospitals in the Netherlands. PARTICIPANTS: One hundred and eighty-eight patient-partner couples were included in this cross-sectional study. MEASUREMENTS: General and clinical characteristics, health status, care dependency, symptoms of anxiety and depression, social support, caregiver burden, and coping styles were assessed during a home visit. RESULTS: Female partners had more symptoms of anxiety and a worse health status than male partners. Social support and caregiver burden were comparable, but coping styles differed between male and female partners. Female partners thought that male patients were less care dependent and had more symptoms of depression, while these gender differences did not exist in patients themselves. CONCLUSION: Health care providers should pay attention to the needs of all partners of patients with COPD, but female partners in particular. Obtaining an extensive overview of the patient-partner couple, including coping styles, health status, symptoms of anxiety, and caregiver burden, is necessary to be able to support the couple as effectively as possible

Prognostic value of free plasma homocysteine levels in patients hospitalized with acute coronary syndrome.

Elevated total plasma homocysteine is an established risk factor for cardiovascular disease. Experimental evidence suggests that non-protein-bound free homocysteine is particularly hazardous to the vascular endothelium. This study evaluates the predictive role of free plasma homocysteine levels on cardiovascular endpoints in patients with acute coronary syndrome (ACS). In a cohort of 379 hospitalized patients with a diagnosis of myocardial infarction or unstable angina pectoris, total and free plasma homocysteine levels were measured by high performance liquid chromatography. The patients were followed for a median 2.7 years. The primary endpoint was a composite of cardiovascular death, myocardial infarction and stroke during follow-up. Stepwise Cox regression was used for multivariate analysis. Primary outcome events occurred in 82 patients (22%) with a median time to event of 6 months. The unadjusted hazard ratio for a free homocysteine level >4.11 micromol/L was 2.16 (95% confidence intervals [CI] 1.36 to 3.42) compared with the 4 lower quintiles. After adjusting for the covariates the hazard ratio was 2.25 (95% CI 1.41 to 3.58, p = 0.01). Compared with the lower 4 quintiles, patients with a total homocysteine level >22.4 micromol/L had a 2.09-fold higher risk (95% CI 1.31 to 3.35) for an event during follow-up. Adjusted for age, discharge diagnosis, serum creatinine, history of atherothrombotic events, and diabetes mellitus, the adjusted hazard ratio was 1.37 (95% CI 0.83 to 2.25, p = 0.22). In conclusion, plasma free homocysteine levels >4.11 micromol/L are a significant and independent risk factor for recurrent cardiovascular events in patients hospitalized for ACS, although total plasma homocysteine levels have no predictive value

A decade of atrial fibrillation ablation shifts in patient characteristics and procedural outcomes

Background Over the past decade, radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) has evolved into a frequently performed procedure. The aim of this study was to monitor changes in patient characteristics, procedural characteristics, outcomes and complications over the past 10 years. Methods All consecutive patients who underwent primary RFCA treatment of AF in the University Medical Center Utrecht from 2005–2015 were included. In all patients, the primary ablation strategy was pulmonary vein (PV) antrum isolation without additional substrate modification. Baseline patient and procedure characteristics, and 1-year follow-up data of 975 patients were prospectively collected. Results In 2005, 73.4% of patients suffered from paroxysmal AF, which decreased to 45.3% in 2014. Mean age increased from 54 ± 9 to 61 ± 10 years and CHA2DS2-VASc score ≥2 from 18 to 40.6%. History of AF decreased significantly from 7 to 4 years. Mean procedure duration was 237 ± 53 min in 2005 and 163 ± 41 min in 2014. Fluoroscopy time significantly decreased from 41 ± 17 to 19 ± 8 min and total radiation exposure from 465 (263–687) to 210 (118–376) mGy. One-year success remained similar (2005: 55.6%, 2014: 54.8%), as did the amount of PV reconnection observed during redo procedures. Due to a marked reduction in vascular complications and moderate PV stenosis, the total complication rate decreased significantly. Conclusion Over the past decade, AF ablation has increasingly been performed in older patients with persistent AF and more comorbidity. Moreover, it has been performed earlier after AF diagnosis. Although several performance parameters, such as procedure duration and complication rate, improved, 1-year single procedure success remained unchanged