982 resultados para heart ventricle isometric contraction
Resumo:
The number of deaths from coronary heart disease in Northern Ireland has dropped significantly, according to recent figures. However, the Public Health Agency is urging everyone to take steps to protect their heart and reduce their chances of developing the disease during National Heart Month (February).Despite the number of deaths dropping significantly in recent years, coronary heart disease is still the number one killer across the country. Over 2,200 people died in Northern Ireland from coronary heart disease in 2010 compared to just over 2,300 people in 2009 - an overall reduction of 100 province-wide. The latest figure reveals the positive downward trend is continuing - in 2008, there were 2,410 deaths, 2,493 in 2007 and 2,554 in 2006, while in 1979 there were nearly 5,000 deaths. Throughout National Heart Month in February, the PHA is calling for people to follow a number of steps in a bid to reduce their chances of developing the disease.Smoking is a major risk factor and, the more cigarettes you smoke, the higher the risk, according to Dr Christine McMaster, Consultant in Public Health Medicine, with responsibility for cardiovascular disease in the PHA."The reduction in smoking over the past number of years through public education, stop smoking programmes and smoke free legislation has had a major impact on reducing deaths from heart disease. However, 24% of the population in Northern Ireland still smoke, putting them at risk of developing the disease."People who suffer from high blood pressure also run an increased risk of developing coronary heart disease. High blood pressure is a silent, but treatable condition. In order to minimise the risk, I would urge everyone over the age of 45 to have their blood pressure measured every five years by their GP," said Dr McMaster.Simple lifestyle changes will also reduce the risk of heart disease, including eating at least five servings of fruit and vegetables a day, avoiding saturated fats, limiting alcohol intake and taking at least 30 minutes of exercise a day, five days a week.Dr McMaster described the reduction in deaths from coronary heart disease over the past few years as "a big success story". "It shows that people can take very positive steps to reduce their risk of heart disease by getting their blood pressure checked and adopting a healthier lifestyle; in particular by not smoking," he added. "The message is clear during National Heart Month - you only have one heart and you can take steps to keep it healthy."
Resumo:
High-dose dobutamine magnetic resonance stress testing has been shown to be superior to dobutamine stress echocardiography for diagnosis of coronary artery disease (CAD). We determined the feasibility of quantitative myocardial tagging during low- and high-dose dobutamine stress and tested the ability of global systolic and diastolic quantitative parameters to identify patients with significant CAD. Twenty-five patients suspected of having significant CAD were examined with a standard high-dose dobutamine/atropine stress magnetic resonance protocol (1.5-T scanner, Philips). All patients underwent invasive coronary angiography as the standard of reference for the presence (n = 13) or absence (n = 12) of significant CAD. During low-dose dobutamine stress, systolic (circumferential shortening, systolic rotation, and systolic rotation velocity) and diastolic (velocity of circumferential lengthening and diastolic rotation velocity) parameters changed significantly in patients without CAD (all P < 0.05 vs. rest) but not in patients with CAD. Identification of patients without and with CAD during low-dose stress was possible using the diastolic parameter of "time to peak untwist." At high-dose stress, none of the global systolic or diastolic parameters showed the potential to identify the presence of significant CAD. With myocardial tagging, a quantitative analysis of systolic and diastolic function was feasible during low- and high-dose dobutamine stress. In our study, the diastolic parameter of time to peak untwist as assessed during low-dose dobutamine stress was the most promising global parameter for identification of patients with significant CAD. Thus quantitative myocardial tagging may become a tool that reduces the need for high-dose dobutamine stress.
Resumo:
Objective: The aim of this study was to investigate the feasibility of transventricular-transseptal approach (TVSA) for extrapleural transcatheter aortic valved stent implantation via a subxyphoidian access. Methods: In five porcine experiments (52.3 +/- 10.9 kg) the right ventricle was exposed via subxyphoidian access. Under the guidance of intracardiac echocardiography (ICE) and fluoroscopy, the transseptal access from right ventricle to left ventricle was created progressively by puncture and dilation with dilators (8F-26F). Valved stents built in-house from commercial tanned pericardium and self-expandable Nitinol stents were loaded into a cartridge. A delivery sheath was then introduced from the right ventricle into the left ventricle and then into the ascending aorta. The cartridge was connected and the valved stent was deployed in the aortic position. Then, the ventricular septal access was sealed with an Amplatzer septal occluder device and the right ventricular access was closed by tying prepared purse-string suture directly. Thirty minutes after the whole procedure, the animals were sacrificed for macroscopic evaluation of the position of valved stent and septal closure device. Result: Procedural success of TVSA was 100% at the first attempt. Mean procedure time was 49 +/- 4 min. Progressive dilatation of the transseptal access resulted in a measurable ventricular septal defect (VSD) after dilator sizes 18F and more. All valved stents were delivered at the target site over the native aortic valve with good acute valve function and no paravalvular leaks. During the procedure, premature beats (5/5) and supraventriclar tachycardias (5/5) were observed, but no atrial-ventricular block (0/5) occurred. Heart rate before (after) was 90 +/- 3 beats min(-1) (100 +/- 2 beats min(-1): p < 0.05), whereas blood pressure was 60 + 1 mm Hg (55 + 2 mm Hg (p < 0.05)). Total blood loss was 280 + 10 ml. The Amplatzer septal occluder devices were fully deployed and the ventricular septal accesses were sealed successfully, without detectable residual shunt. Conclusion: Trans-catheter implantation of aortic valved stent via extrapleural transventricular-transseptal access is technically feasible and has the potential for a simplified procedure under local anaesthesia. (C) 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B. V. All rights reserved.
Resumo:
INTRODUCTION: The spatio-temporal pattern of arrhythmias in the embryonic/fetal heart subjected to a transient hypoxic or hypothermic stress remains to be established. METHODS AND RESULTS: Spontaneously beating hearts or isolated atria, ventricles, and conotruncus from 4-day-old chick embryos were subjected in vitro to 30-minute anoxia and 60-minute reoxygenation. Hearts were also submitted to 30-minute hypothermia (0-4 degrees C) and 60-minute rewarming. ECG disturbances and alterations of atrial and ventricular electromechanical delay (EMD) were systematically investigated. Baseline functional parameters were stable during at least 2 hours. Anoxia induced tachycardia, followed by bradycardia, atrial ectopy, first-, second-, and third-degree atrio-ventricular blocks and, finally, transient electromechanical arrest after 6.8 minutes, interquartile ranges (IQR) 3.1-16.2 (n = 8). Reoxygenation triggered also Wenckebach phenomenon and ventricular escape beats. At the onset of reoxygenation QT, PR, and ventricular EMD increased by 68%, 70%, and 250%, respectively, whereas atrial EMD was not altered. No fibrillations, no ventricular ectopic beats, and no electromechanical dissociation were observed. Arrhythmic activity of the isolated atria persisted throughout anoxia and upon reoxygenation, whereas activity of the isolated ventricles abruptly ceased after 5 minutes of anoxia and resumed after 5 minutes of reoxygenation. During hypothermia-rewarming, cardiac activity stopped at 17.9 degrees C, IQR 16.2-20.6 (n = 4) and resumed at the same temperature with no arrhythmias. All preparations fully recovered after 40 minutes of reoxygenation or rewarming. CONCLUSION: In the embryonic heart, arrhythmias mainly originated in the sinoatrial tissue and resembled those observed in the adult heart. Furthermore, oxygen readmission was by far more arrhythmogenic than rewarming and the chronotropic, dromotropic, and inotropic effects were fully reversible.
Resumo:
The role of Older People's Commissioner for Wales was created with a range of powers to help improve the lives of older people in Wales. This is the first Commission of its kind. Many groups and individuals worked to bring this independent post into being, and the Commissioner's powers reflect their serious intent to challenge the barriers and discrimination that face older people.
Resumo:
Calomys callosus, a sylvatic reservoir of Trypanosoma cruzi, when infected with the Colombian strain (Biodeme Type III, T. cruzi I ) develops necrotic-inflammatory lesions and intense early fibrogenesis in the heart and skeletal muscles, that spontaneously regress. Participation of pro-inflammatory and pro-fibrogenic cytokines, such as tumor necrosis factor-alpha (TNF-alpha), gamma interferon (IFN-gamma) , and tumor growth factor-beta (TGF-beta), in the pathogenesis of the lesions is herein studied. Eighty C. callosus weighing 20 to 30 g were used. Seventy of them were inoculated with the Colombian strain (10(5) blood forms) and 10 were maintained as intact non-infected controls. After infection, C. callosus were sacrificed at different time-points from 15 to 70 days. The heart and skeletal muscle were processed for histopathology and cryopreserved for immunohistochemistry. Early necrotic lesions of parasitized skeletal muscle and myocardium with intense inflammatory lesions were present. Search for the in situ presence of TNF-alpha and IFN-gamma, was performed using rat-IgG anti-mouse antibodies against these cytokines. For the in situ search of TGF-beta, rabbit IgG anti-mouse antibodies were used. Immunolabeling of the cytokines in tissues of infected C. callosus was successful. The cytokines TNF-alpha, IFN-gamma , and TGF-beta were detected in the cytoplasm of macrophages and in the necrotic material from 15 to 45 days post-infection, decreasing their intensity until complete disappearance by the 65th day, which correlated with subsiding histopathological lesions. These findings suggest the participation of these cytokines in the control of parasite multiplication, in the development of an early fibrogenesis and in the regression of fibrotic-inflammatory lesions observed in C. callosus.
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.
Resumo:
This briefing considers the national health inequalities targets which must be met by 2010. The targets include those set for heart disease and stroke, cancers and life expectancy.
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.
Resumo:
The Atripump is a motorless, volume displacement pump based on artificial muscle technology that could reproduce the pump function of normal atrium. It could help prevent blood clots due to blood stagnation and eventually avoid anticoagulation therapy in atrial fibrillation (AF). An animal study has been designed to assess mechanical effects of this pump on fibrillating atrium. The Atripump is a dome shaped silicone coated nitinol actuator. A pacemaker like control unit drives the actuator. In five adult sheep, the right atrium (RA) was exposed and dome sutured onto the epicardium. Atrial fibrillation was induced using rapid epicardial pacing (600 beats/min). Ejection fraction of the RA was obtained with intracardiac ultrasound in baseline, AF and Atripump assisted AF conditions. The dome's contraction rate was 60/min with power supply of 12V, 400 mA for 200 ms and ran for 2 hours in total. Mean temperature on the RA was 39+/-1.5 degrees C. Right atrium ejection fraction was 31% in baseline conditions, 5% and 20% in AF and assisted AF, respectively. In two animals a thrombus appeared in the right appendix and washed out once the pump was turned on. The Atripump washes blood out the RA acting as an anticoagulant device. Possible clinical implications in patients with chronic AF are prevention of embolism of cardiac origin and avoidance of hemorrhagic complication due to chronic anticoagulation.
Resumo:
Your views matter - if you have heart failure, or are close to someone who does, please complete our survey by 31st�March 2012 (link below).Heart failure is a common condition affecting at least 20,000 people in Northern Ireland. The aim of this survey is to find out how to increase the confidence of people living with heart failure so they have a better quality of life, and can work in partnership with health care professionals and support services in managing their condition. The findings of this survey will be used to help improve services.Your views are important and we would encourage you to complete the survey. It should only take around 20 minutes. Participation is confidential which means that your identity will not be revealed. You are asked for your age, the first part of you post code and which GP practice you are registered with. This is so the results for different age groups and for different large geographical areas (i.e. Health & Social Care Trust areas) can be compared.� Results will not be examined by individual GP practice.Participation is voluntary i.e. taking part in the study is your decision. Whether you participate or not will have no effect on the medical care you receive from your GP practice or elsewhere. None of the health care professionals involved in your care will know if you participate or not: neither will they see your individual response.Whether you are an adult or a young person living with heart failure, or a partner, care giver, son, daughter, relative or friend, we would like you to share your experiences. This will help us to develop existing services in Northern Ireland to better meet your needs.You can share your experience by completing the survey online, clicking this�link:�http://sg.sensemaker-suite.com/CopewithconfidenceThe survey should be completed by 31st�March 2012.�If you have any queries about the survey, or you would like to request a paper copy to complete, please contact the Public Health Agency (028) 9032 1313 and ask for extension 2487 or email us at copewithconfidence@hscni.netPlease note that the survey team can only assist in survey related questions and will not able to answer questions about heart failure, its treatment or services provided.The Northern Ireland Chest Heart & Stroke Association and The British Heart Foundation can provide information about support available to people with heart failure. Their contact details are:.�Northern Ireland Chest Heart and Stroke Association:� www.nichsa.com, telephone (028) 9032 0184.�British Heart Foundation:� www.bhf.org.uk, telephone 0300 330 3311
Resumo:
BACKGROUND: Both systolic and diastolic dysfunction have been observed in patients with anterolateral myocardial infarction. Diastolic dysfunction is related to disturbances in relaxation and diastolic filling. OBJECTIVE: To analyse cardiac rotation, regional shortening and diastolic relaxation in patients with anterolateral infarction. METHODS: Cardiac rotation and relaxation in controls and patients with chronic anterolateral infarction were assessed by myocardial tagging. Myocardial tagging is based on magnetic resonance imaging and allows us to label specific myocardial regions for imaging cardiac motion (rotation, translation and radial displacement). A rectangular grid was placed on the myocardium (basal, equatorial and apical short-axis plane) of each of 18 patients with chronic anterolateral infarction and 13 controls. Cardiac rotation, change in area and shortening of circumference were determined in each case. RESULTS: The left ventricle in controls performs a systolic wringing motion with a clockwise rotation at the base and a counterclockwise rotation at the apex when viewed from the apex. During relaxation a rotational motion in the opposite direction (namely untwisting) can be observed. In patients with anterolateral infarction, there is less systolic rotation at the apex and diastolic untwisting is delayed and prolonged in comparison with controls. In the presence of a left ventricular aneurysm (n = 4) apical rotation is completely lost. There is less shortening of circumference in infarcted and remote regions. CONCLUSIONS: The wringing motion of the myocardium might be an important mechanism involved in maintaining normal cardiac function with minimal expenditure of energy. This mechanism no longer operates in patients with left ventricular aneurysms and operates significantly less than normal in those with anterolateral hypokinaesia. Diastolic untwisting is significantly delayed and prolonged in patients with anterolateral infarction, which could explain the occurrence of diastolic dysfunction in these patients.
Resumo:
A case-control study on chronic Chagas heart disease (CCHD) was carried out between 1997 and 2005. Ninety patients over 50 years of age were examined for factors related to (CCHD). Fourty-six patients (51.1%) with Chagas heart disease (anomalous ECG) were assigned to the case group and 44 (48.9%) were included in the control group as carriers of undetermined forms of chronic disease. Social, demographic (age, gender, skin color, area of origin), epidemiological (permanence within an endemic zone, family history of Chagas heart disease or sudden death, physical strain, alcoholism, and smoking), and clinical (systemic hypertension) variables were analyzed. The data set was assessed through single-variable and multivariate analysis. The two factors independently associated with heart disease were age - presence of heart disease being three times higher in patients over 60 years of age (odds ratio, OR: 2.89; confidence interval of 95%: 1.09-7.61) - and family history of Chagas heart disease (OR: 2.833, CI 95%: 1.11-7.23). Systemic hypertension and gender did not prove to hold any association with heart disease, as neither did skin color, but this variable showed low statistical power due to reduced sample size.