View clinical trials related to Sudden Cardiac Death.
Filter by:Arrhythmias remain a major health problem, causing at least 250,000 deaths annually in the United States. Pharmacological treatments often do more harm than good, and device therapies are limited by high cost and effects on quality of life. Ion channel mutations cause rare inherited arrhythmopathies, but account for only a small fraction of patients with life- threatening arrhythmias and sudden death. Most arrhythmias occur during myocardial ischemia, following myocardial infarction, and in patients with poor left ventricular (LV) function of any etiology. Aside from ejection fraction (EF), few clinically useful indicators to stratify the risk of sudden death have been identified. The role of subtle difference in ion channel expression and/or structure in predisposing patients to arrhythmias and modulating the risk of sudden death is unknown. In this study, we are prospectively testing whether polymorphisms in ion channels and ion channel modifying genes are associated with arrhythmias in a population with internal cardioverter-defibrillators (ICDs) and poor LV function. We will test the hypothesis that functional polymorphisms in the coding sequences and promoter regions of cardiac genes (e.g. ion channels, beta-adrenergic receptors) predispose individuals to arrhythmias and /or heart failure progression. We hope to identify genetic predictors for the common forms of sudden cardiac death. This would allow the identification of a subpopulation of heart failure patients that would benefit most from ICD placement.
The purpose of this study is to test the acceptability and feasibility of a "toolkit" of patient decision aids (PtDAs) for heart failure patients who are considering an ICD implant.
Worldwide three million people a year die from sudden cardiac death (SCD). In most cases there is no warning and the heart is stopped by a sudden arrhythmia. We know that some people are at high risk of sudden cardiac death and can prevent their deaths with an implantable cardioverter defibrillator (ICD) that is implanted in a minor operation. However, most people who die from sudden cardiac death are not found to be at high risk by our current risk markers and 40% of the people who have ICDs do not have therapy within the first 4 years after implant. We need new and better ways of identifying people who are at high risk of sudden cardiac death so that we can prevent their deaths with ICDs. Our understanding of the electrical signals in the heart has increased considerably in recent years; in no small part this is due to our Principal Investigator Professor Andre Ng's basic science work. This study aims to take the understanding of action potential duration (APD) restitution gained through our work and other studies in humans and in computer simulations and translate it into a fresh way of assessing risk of sudden cardiac death. This study will carefully examine electrical activity, using APD restitution, in the hearts of patients who are having ICDs fitted because of their high risk of sudden cardiac death and combine this with a detailed heart scan, assessment of autonomic nervous system and gene expression data. We will then follow these patients up to see who benefits from their ICD. This wide ranging information will give us as complete a picture as possible of the factors that cause sudden cardiac death. We hope to use this to identify better predictors of sudden cardiac death. The study hypotheses are as follows: Primary 1. Regional Restitution Instability Index (R2I2) will be significantly higher in patients reaching the endpoint of ventricular endpoint / sudden cardiac death than in those not. 2. An R2I2 cut-off of 1.03 will partition patients into high and low risk groups. Secondary 3. Peri-infarct zone mass in grams will be significantly higher in patients reaching the endpoint of ventricular endpoint / sudden cardiac death than in those not.
Despite pharmacologic advances for the treatment of congestive heart failure (HF), sudden cardiac death (SCD) and pump failure remain the leading causes of mortality in patients with HF. Although, SCD is poorly understood, implantable cardiac defibrillators (ICD) have been shown to be an effective, but costly therapy in preventing SCD. At present, left ventricular systolic dysfunction is our best independent predictor of SCD, but only moderately predicts those patients who will eventually benefit from the placement of an ICD and, in most cases, left ventricular (LV) systolic dysfunction is a non-modifiable risk factor once acquired. As a result, there exists an intensive search for biomarkers that could improve the prediction of SCD and have the potential for risk factor modification. Experimental and clinical evidence has established that inflammation plays a critical role in stable coronary disease, plaque rupture, acute myocardial infarction, heart failure, and SCD. Studies at our institution have demonstrated that elevated levels of hsCRP and Interleukin-6 are predictive of arrhythmic SCD; however, the mechanism of causing this increased risk is unclear. Another well-known risk factor for SCD is abnormal sympathetic innervation. The most robust clinical test of sympathetic innervation to date is Iodine-123 Metaiodobenzylguanidine (MIBG) imaging with gamma scintigraphy. MIBG imaging has emerged as one of our strongest predictors of SCD by detecting sympathetic nervous system abnormalities in patients with HF. Preclinical and clinical evidence suggests that myocardial inflammation adversely affects myocardial innervation. Based on these findings, the investigators hypothesize that elevated levels of inflammatory biomarkers are associated with abnormal sympathetic innervation as measured by MIBG imaging. The investigators aim to establish the strength of this association. This proposal will leverage unique access to the largest, most extensively phenotyped cohort of patients who have undergone ICD implantation for primary prevention of SCD, the PRospective Observational Study of the ICD in SCD, (PROSE-ICD).
Sudden cardiac death (SCD) due to a ventricular arrhythmia is a serious cause of cardiovascular death in Canada. The implantable cardioverter defibrillator (ICD) offers high-risk patients a treatment option to reduce the incidence of SCD by delivering an internal shock to restore a normal rhythm, if needed. Definitive evidence has established the effectiveness of the ICD for reducing mortality when used as prophylaxis for SCD (a primary prevention indication). Approximately 3,700 new candidates accrue annually. Practice guidelines define the criteria to determine patient ICD candidacy for primary prevention. However, in addition to SCD risk, ICD candidates may have chronic diseases such as diabetes, renal insufficiency, hypertension, and atrial fibrillation. Thus, balancing the benefits and risks of an ICD can become complex, particularly when competing mortality risks are present. Research has recognized human costs associated with device complications and shocks affecting psychological, health related quality of life (HRQL), and morbidity outcomes. The complexities surrounding the long-term benefits/risks, complications, replacements, and shocks, warrant decision support to prepare patients to make decisions. In Canada, there is no clear framework to support patients' decision-making in the context of ICD treatment options. Decision support, using a decision aid, could moderate treatment related uncertainty and prepare patients to make active, informed, quality decisions. Objectives: 1) develop a decision aid for ICD candidates to support quality decision-making (informed, deliberate, values-based choices), 2) to evaluate the decision aid, and 3) to determine the feasibility of conducting a trial.
The purpose of this study is to determine whether a blunted heart rate response to regadenoson is an independent predictor of sudden cardiac death.
The purpose of the study is to proof the safety and efficacy of the new ICD sytem (Iforia/Ilesto). The devices are available with DF-1 and DF4 connection. A special focus is set on the ICD system with DF4 connection.
Despite advances in treatment of conventional cardiovascular risk factors, patients with kidney disease remain at high risk for fatal cardiac events. To date, kidney disease affects approximately 2 million Canadians; however, this patient population remains grossly understudied due to the complex nature of the disease. The inadequacy of the literature to address the cardiovascular-related mortality rates in those with kidney disease reflects the urgent need for investigation of novel risk factors. One cardiovascular risk factor which has recently been validated is the clinical measurement of cardiac autonomic tone (CAT). CAT refers to the amount of activity contributed by the stimulatory and inhibitory limbs of the cardiac autonomic nervous system, which work in concert with one another to control heart rate. CAT can be quantified computer analysis of heart rate over time, captured by a simple Holter electrocardiogram (ECG) recording. Abnormal CAT, which occurs when the autonomic system does not control heart rate properly in response to physical demands or stress, is associated with risk of adverse cardiovascular events in both healthy and high risk populations. It has recently been shown that patients with severe kidney disease demonstrate significant CAT abnormalities, thus exaggerated susceptibility to cardiac death. Vitamin D (VD) deficiency is also common in this patient population due to the fact that the kidney plays a crucial role in VD metabolism. Given that VD deficiency is an established cardiovascular risk factor on its own, it is possible that kidney disease patients experienced compounded risk due to the combination of VD deficiency and abnormal CAT. However, no study has ever investigated whether VD deficiency influences CAT in healthy or diseased populations. To our knowledge, this will be the first trial to ever examine the effect, if any, of different VD supplementation treatments (standard of care vs. combination) on CAT in a population burdened with overwhelming risk and incidence of cardiovascular and sudden cardiac death risk.
The purpose of this study is to assess the effect of stearidonic acid when used as a food ingredient on eicosapentaenoic enrichment of red blood cell membranes and Omega-3 Index in men and women.
In this study, we are comparing the difference in outcomes between patients who were given shocks to the heart, during the upstroke of cardiopulmonary resuscitation (CPR) and before CPR is started. The study population will be all cardiac arrest patients attended by the staff of the Emergency Department who fulfil the eligibility criteria. Patients will be managed according to currently approved cardiac arrest protocols. Patients confirmed in cardiac arrest have manual chest compressions started while mechanical CPR (whereby chest compressions are delivered by an automated device) is prepared. Mechanical CPR should be started as soon as possible (<1 minute). If patients are eligible to be shocked, they will receive shocks either during upstroke of CPR or before CPR is started. Thus the purpose of this study is to answer the question whether are there improvement in survival between when shocks are given during upstroke and before CPR is started.