897 resultados para CORONARY VESSELS


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Résumé Introduction: La perfusion isolée cytostatique du poumon est une technique attractive qui permet l'administration des doses élevées d'un agent cytostatique tout en épargnant dans la mesure du possible la circulation systémique. Cependant, la perfusion de l'artère pulmonaire risque d'épargner le territoire pulmonaire vascularisé par l'intermédiaire des artères bronchiques, ce qui pourrait diminuer l'efficacité de ce traitement au cas où la lésion ciblée est vascularisée par les artères bronchiques. Ce travail est destiné au développement d'un modèle tumoral au niveau des poumons de rongeur (rat) porteur d'un sarcome pulmonaire afin de déterminer si la voie d'injection des cellules tumorales (intraveineuse, versus intratumorale) influencera la vascularisation des tumeurs (provenant du système artères pulmonaires ou artères bronchiques). Méthod: Des tumeurs de sarcomes pulmonaires ont été générées par injection d'une suspension cellulaire de sarcome, soit par injection intraveineuse, soit directement dans le parenchyme pulmonaire par thoracotomie. Ensuite, une perfusion isolée du poumon porteur de la tumeur à l'aide de l'encre a été effectuée, soit par l'artère pulmonaire, soit par le système des artères bronchiques. La distribution de l'encre dans les vaisseaux tumoraux ainsi que dans les vaisseaux non tumoraux du poumon adjacent a été investiguée à l'aide d'une analyse histologique des poumons perfusés. Résultat: L'administration intraveineuse et intratumorale de la suspension de cellules tumorales résulte en des tumeurs similaires sur le plan histologique. Néanmoins, l'injection intra-parenchymateuse démontre des tumeurs plus homogènes et avec un développement plus prédictible, était associée à une survie plus longue qu'après injection intraveineuse. Les analyses histologiques après perfusion isolée à l'aide de l'encre démontre que les tumeurs résultant de l'injection intraveineuse ont développé une vascularisation se basant sur le système d'artères pulmonaires tandis que les tumeurs émergeant après injection intraparenchymateuse ont développé une vascularisation provenant du système des artères bronchiques. Conclusion: Ce travail démontre pour la première fois l'importance du mode de génération de tumeurs pulmonaires en ce qui concerne leur future vascularisation, ce qui pourrait avoir un impact sur leur traitement par perfusion isolée du poumon. Abstract Isolated cytostatic lung perfusion (ILP) is an attractive technique allowing delivery of a high-dose of cytostatic agents to the lungs while limiting systemic toxicity. In developing a rat model of ILP, we have analysed the effect of the route of tumour cell injection on the source of tumour vessels. Pulmonary sarcomas were estab¬lished by injecting a sarcoma cell suspension either by the intravenous (i.v.) route or directly into the lung paren¬chyma. Ink perfusion through either pulmonary artery (PA) or bronchial arteries (BA) was performed and the characteristics of the tumour deposits defined. i.v. and direct injection methods induced pulmonary sarcoma nodules, with similar histological features. The intraparenchymal injection of tumour cells resulted in more reli¬able and reproducible tumour growth and was associat¬ed with a longer survival of the animals. i.v. injected tumours developed a PA-derived vascular tree whereas directly injected tumours developed a BA-derived vasculature.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

PURPOSE: To investigate the feasibility of high-resolution selective three-dimensional (3D) magnetic resonance coronary angiography (MRCA) in the evaluation of coronary artery stenoses. MATERIALS AND METHODS: In 12 patients with coronary artery stenoses, MRCA of the coronary artery groups, including the coronary segments with stenoses of 50% or greater based on conventional x-ray coronary angiography (CAG), was performed with double-oblique imaging planes by orienting the 3D slab along the major axis of each right coronary artery-left circumflex artery (RCA-LCX) group and each left main trunk-left anterior descending artery (LMT-LAD) group. Ten RCA-LCX and five LMT-LAD MR angiograms were obtained, and the results were compared with those of conventional x-ray angiography. RESULTS: Among 70 coronary artery segments expected to be covered, a total of 49 (70%) segments were fully demonstrated in diagnostic quality. The identification of segmental location of stenoses showed as high an accuracy as 96%. The retrospective analysis for stenosis of 50% or greater yielded the sensitivity, specificity, and accuracy of 80%, 85%, and 84%, respectively. CONCLUSION: Selective 3D MRCA has the potential for segment-by-segment evaluation of major portions of the right and left coronary arteries with high accuracy.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Emergency Department Assessment of Women with Acute Coronary Syndrome Click here to download PDF 353kb

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Navigator-gated and corrected 3D coronary MR angiography (MRA) allows submillimeter image acquisition during free breathing. However, cranial diaphragmatic drift and relative phase shifts of chest-wall motion are limiting factors for image quality and scanning duration. We hypothesized that image acquisition in the prone position would minimize artifacts related to chest-wall motion and suppress diaphragmatic drift. Twelve patients with radiographically-confirmed coronary artery disease and six healthy adult volunteers were studied in both the prone and the supine position during free-breathing navigator-gated and corrected 3D coronary MRA. Image quality and the diaphragmatic positions were objectively compared. In the prone position, there was a 36% improvement in signal-to-noise ratio (SNR; 15.5 +/- 2.7 vs. 11.4 +/- 2.6; P < 0.01) and a 34% improvement in CNR (12.5 +/- 3.3 vs. 9.3 +/- 2.5, P < 0.01). The prone position also resulted in a 17% improvement in coronary vessel definition (P < 0.01). Cranial end-expiratory diaphragmatic drift occurred less frequently in the prone position (23% +/- 17% vs. 40% +/- 26% supine; P <0.05), and navigator efficiency was higher. Prone coronary MRA results in improved SNR and CNR with enhanced coronary vessel definition. Cranial end-expiratory diaphragmatic drift also was reduced, and navigator efficiency was enhanced. When feasible, prone imaging is recommended for free-breathing coronary MRA.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: The optimal coronary MR angiography sequence has yet to be determined. We sought to quantitatively and qualitatively compare four coronary MR angiography sequences. SUBJECTS AND METHODS. Free-breathing coronary MR angiography was performed in 12 patients using four imaging sequences (turbo field-echo, fast spin-echo, balanced fast field-echo, and spiral turbo field-echo). Quantitative comparisons, including signal-to-noise ratio, contrast-to-noise ratio, vessel diameter, and vessel sharpness, were performed using a semiautomated analysis tool. Accuracy for detection of hemodynamically significant disease (> 50%) was assessed in comparison with radiographic coronary angiography. RESULTS: Signal-to-noise and contrast-to-noise ratios were markedly increased using the spiral (25.7 +/- 5.7 and 15.2 +/- 3.9) and balanced fast field-echo (23.5 +/- 11.7 and 14.4 +/- 8.1) sequences compared with the turbo field-echo (12.5 +/- 2.7 and 8.3 +/- 2.6) sequence (p < 0.05). Vessel diameter was smaller with the spiral sequence (2.6 +/- 0.5 mm) than with the other techniques (turbo field-echo, 3.0 +/- 0.5 mm, p = 0.6; balanced fast field-echo, 3.1 +/- 0.5 mm, p < 0.01; fast spin-echo, 3.1 +/- 0.5 mm, p < 0.01). Vessel sharpness was highest with the balanced fast field-echo sequence (61.6% +/- 8.5% compared with turbo field-echo, 44.0% +/- 6.6%; spiral, 44.7% +/- 6.5%; fast spin-echo, 18.4% +/- 6.7%; p < 0.001). The overall accuracies of the sequences were similar (range, 74% for turbo field-echo, 79% for spiral). Scanning time for the fast spin-echo sequences was longest (10.5 +/- 0.6 min), and for the spiral acquisitions was shortest (5.2 +/- 0.3 min). CONCLUSION: Advantages in signal-to-noise and contrast-to-noise ratios, vessel sharpness, and the qualitative results appear to favor spiral and balanced fast field-echo coronary MR angiography sequences, although subjective accuracy for the detection of coronary artery disease was similar to that of other sequences.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

ABSTRACT: BACKGROUND: Chest pain raises concern for the possibility of coronary heart disease. Scoring methods have been developed to identify coronary heart disease in emergency settings, but not in primary care. METHODS: Data were collected from a multicenter Swiss clinical cohort study including 672 consecutive patients with chest pain, who had visited one of 59 family practitioners' offices. Using delayed diagnosis we derived a prediction rule to rule out coronary heart disease by means of a logistic regression model. Known cardiovascular risk factors, pain characteristics, and physical signs associated with coronary heart disease were explored to develop a clinical score. Patients diagnosed with angina or acute myocardial infarction within the year following their initial visit comprised the coronary heart disease group. RESULTS: The coronary heart disease score was derived from eight variables: age, gender, duration of chest pain from 1 to 60 minutes, substernal chest pain location, pain increases with exertion, absence of tenderness point at palpation, cardiovascular risks factors, and personal history of cardiovascular disease. Area under the receiver operating characteristics curve was of 0.95 with a 95% confidence interval of 0.92; 0.97. From this score, 413 patients were considered as low risk for values of percentile 5 of the coronary heart disease patients. Internal validity was confirmed by bootstrapping. External validation using data from a German cohort (Marburg, n = 774) revealed a receiver operating characteristics curve of 0.75 (95% confidence interval, 0.72; 0.81) with a sensitivity of 85.6% and a specificity of 47.2%. CONCLUSIONS: This score, based only on history and physical examination, is a complementary tool for ruling out coronary heart disease in primary care patients complaining of chest pain.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Atrial fibrillation (AF) is a frequent arrhythmia after conventional coronary artery bypass grafting. With the advent of minimally invasive technique for left internal mammary artery-left anterior descending coronary artery (LIMA-LAD) grafting, we analyzed the incidence and the risk factors of postoperative AF in this patient population. This prospective study involves all patients undergoing isolated LIMA-LAD grafting with minimally invasive technique between January 1994 and June 2000. Twenty-four possible risk factors for postoperative AF were entered into univariate and multivariate logistic regression analyses. Postoperative AF occurred in 21 of the 90 patients (23.3%) analyzed. Double- or triple-vessel disease was present in 12/90 patients (13.3%). On univariate analysis, right coronary artery disease (p <0.01), age (p = 0.01), and diabetes (p = 0.04) were found to be risk factors for AF. On multivariate analysis, right coronary artery disease was identified as the sole significant risk factor (p = 0.02). In this patient population, the incidence of AF after minimally invasive coronary artery bypass is in the range of that reported for conventional coronary artery bypass grafting. Right coronary artery disease was found to be an independent predictor, and this may be related to the fact that in this patient population the diseased right coronary artery was not revascularized at the time of the surgical procedure. For the same reason, this risk factor may find a broader application to noncardiac thoracic surgery.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

On World Heart Day, 29 September 2011, the Public Health Agency is urging all smokers to stop smoking and reduce their risk of developing heart disease (cardiovascular disease - CVD) or suffering a stroke or a heart attack.Heart disease is one of the leading causes of death and illness in the UK. Research shows that smoking is one of the main contributors of the disease, causing around 25,000 deaths a year in the UK. Cigarette smokers are two times more likely than non-smokers to suffer a heart attack.The majority of people who suffer a heart attack before the age of 50 are smokers. Cigarette smoke causes heart disease by:· reducing oxygen to the heart;· increasing blood pressure and heart rate;· increasing blood clotting;· damaging cells that line coronary arteries and other blood vessels, causing narrowing of the arteries.From the moment smoke reaches your lungs, your heart is forced to work harder. Your pulse quickens, forcing your heart to beat an extra 10 to 25 times per minute, as many as 36,000 additional times per day. Because of the irritating effect of nicotine and other components of tobacco smoke, your heartbeat is more likely to be irregular. This can contribute to cardiac arrhythmia and many other serious coronary conditions, such as heart attack.For smokers who already suffer from heart problems, quitting will dramatically help. Many heart patients notice an almost immediate improvement when they stop smoking. Often, they need less medication and can cope better with physical exertion.Gerry Bleakney, Head of Health and Social Wellbeing Improvement, PHA, said: "Smoking is one of the major causes of cardiovascular disease and smokers are almost twice as likely to have a heart attackas someone who has never smoked. One in every two long-term smokers will die prematurely from smoking-related diseases, many suffer very poor health before they die. However one year after successfully quitting smoking, an individual will have reduced their risk of having a heart attack to half that of a person continuing to smoke."Across Northern Ireland, there are over 600 support services for people who wish to stop smoking, based in GP surgeries, community pharmacies, hospitals, community centres and workplaces. I would encourage everyone who is thinking about quitting to log on to our Want 2 Stop website: www.want2stop.info and order a 'Quit Kit' free of charge alternatively contact the Smokers' Helpline on 0808 812 8008."

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Atresia of the coronary sinus (ACS) is a rare congenital anomaly. When associated with persistent left superior vena cava (PLSVC), this defect could have no significant hemodynamic effect, and the patient might remain asymptomatic. However, vascular interventions might induce changes or complications that could show the anomaly. Appropriate management requires a good understanding of this condition. We present the first reported case of ACS and PLSVC occurring after thrombosis of the innominate vein (IV) after central venous catheter placement. The patient presented with atypical subacute chest pain and recurrent extrasystoles. Diagnosis and characterization of vascular anomalies was made by computed tomography phlebography, and the patient was successfully managed by endovascular recanalization of the IV.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: After age, sex is the most important risk factor for coronary artery disease (CAD). The mechanism through which women are protected from CAD is still largely unknown, but the observed sex difference suggests the involvement of the reproductive steroid hormone signaling system. Genetic association studies of the gene-encoding Estrogen Receptor α (ESR1) have shown conflicting results, although only a limited range of variation in the gene has been investigated. METHODS AND RESULTS: We exploited information made available by advanced new methods and resources in complex disease genetics to revisit the question of ESR1's role in risk of CAD. We performed a meta-analysis of 14 genome-wide association studies (CARDIoGRAM discovery analysis, N=≈87,000) to search for population-wide and sex-specific associations between CAD risk and common genetic variants throughout the coding, noncoding, and flanking regions of ESR1. In addition to samples from the MIGen (N=≈6000), WTCCC (N=≈7400), and Framingham (N=≈3700) studies, we extended this search to a larger number of common and uncommon variants by imputation into a panel of haplotypes constructed using data from the 1000 Genomes Project. Despite the widespread expression of ERα in vascular tissues, we found no evidence for involvement of common or low-frequency genetic variation throughout the ESR1 gene in modifying risk of CAD, either in the general population or as a function of sex. CONCLUSIONS: We suggest that future research on the genetic basis of sex-related differences in CAD risk should initially prioritize other genes in the reproductive steroid hormone biosynthesis system.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This editorial refers to the Management and 6-month outcomes in elderly and very elderly patients with high-risk non-ST-elevation acute coronary syndromes: In the well developed countries of the world, ischaemic heart disease is the prevailing cause of death among patients aged >65 years. In Europe, more than in other countries in the world, we will witness during the next few decades a dramatic surge of patients with ischaemic heart disease due to the progressive ageing of our population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This is the seventeenth edition of "Coronary Heart Disease Statistics" published by the British Heart Foundation. The series of publications aims to document the burden of coronary heart disease (CHD) in the United Kingdo. It also includes information on other cardiovascular conditions including stroke and heart failure and includes sections on cardiovascular risk factors.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This report details the progress which has been made in implementing the Coronary Heart Disease National Service Framework in the eight years since its publication.