The Genetics of Dilated Cardiomyopathy: A Quebec-Based Study
Dilated Cardiomyopathy (DCM)Dilated cardiomyopathy (DCM) affects about 200,000 Canadians. Eighty percent of these cases are of unclear cause, often occuring in families. We believe that mutations in specific already-identified genes contribute to DCM in Quebec and that certain mutations may account for a significant proportion of cases due to the well-documented "founder effect". Two hundred patients with DCM followed in our Heart Function Clinic will be approached for one blood sample at their routine clinic visit to test this hypothesis. The samples will be tested in the Laboratory of Cardiovascular Genetics at the Royal Victoria Hospital.
Echo Assessment of Intraventricular Dyssynchrony
Chronic Heart FailureIschemic Heart Disease1 moreBackground. Clinical benefits of cardiac resynchronization therapy (CRT) have been clearly demonstrated in heart failure (HF) patients with severe left ventricular (LV) dysfunction and wide QRS at surface electrocardiogram. However, there is a growing evidence that QRS duration poorly predicts responses to CRT, and that ~30% of patients do not experience any benefit from CRT when pre-implant dyssynchrony is defined according to electrocardiographic criteria. A number of echocardiographic criteria have been proposed to assess mechanical LV dyssynchrony, but at present there is no consensus on their use to predict response to CRT. Study Design. The Italian Multicenter PROject on echo assessment of left VEntricular (IMPROVE) dyssynchrony study is a prospective, multicenter, observational study aimed to assess feasibility and predictive power of mechanical dyssynchrony assessed by echocardiography in consecutive consenting patients candidate to CRT by clinical and electrocardiographic criteria. IMPROVE will enroll 120 healthy subjects and 216 HF patients in 6 sites in Italy. CRT response criteria will be based on improvement in NYHA class and LV reverse remodeling evaluated by 3D-echocardiography. Enrollment is expected to conclude early 2009. Implications. CRT is today part of the therapeutic armamentarium for symptomatic HF patients refractory to medical therapy, with wide QRS complex and severe LV systolic dysfunction. The IMPROVE study has been designed to evaluate reference values of indexes of ultrasound mechanical dyssynchrony that have been proposed in the literature and compare their ability to predict response to CRT in HF patients.
Duchenne Muscular Dystrophy Heart Study
Duchenne Muscular DystrophyDuchenne Muscular Dystrophy-Associated Dilated CardiomyopathyRetrospective cohort study including patients with genetically proven Duchenne muscular dystrophy, diagnosed from January 1993 to March 2020. Inclusion of the data relative to genetic diagnosis, clinical characteristics at baseline, cardiac and respiratory workup, medical treatments (ACE inhibitors, steroids), surgical procedures, and occurrence during follow-up of cardiac, respiratory and fatal events. Objectives are to describe long-term natural history of the disease, vital prognosis, genotype-phenotype correlations, effect of treatments.
Prospective Becker-Heart-Study
Dilated CardiomyopathyLef Ventricular Dysfunction1 moreThe purpose of this study is to determine whether electrocardiogram, echocardiography, cardiac MRI, sera biomarkers can improve early detection of myocardial involvement and clinical outcome.
Effects of HTEA ON Heart Failure Secondary to Idiopathic Dilated Cardiomyopathy or Post-myocardial...
Congestive Heart FailureThe investigators would evaluate the effects of the novel method, HTEA on cardiac function in the heart failure patients secondary to idiopathic dilated cardiomyopathy and post-myocardial infarction.
Manganese-Enhanced Magnetic Resonance Imaging of the Myocardium
Ischemic CardiomyopathyDilated Cardiomyopathy1 moreScanning the heart using magnetic resonance imaging (MRI) enables detailed assessment of its structure and function. MRI can give more detailed information about the heart by using a contrast 'dye' that is injected into a vein during the scan. This can highlight abnormal areas within the heart. Current contrast dyes help identify scarring within the heart, which is useful in people who have had heart attacks. The investigators plan to test new contrast dye containing manganese, which works differently to current agents. They believe it will provide unique insight into how the heart works. There are many different causes of heart problems and the investigators plan to use this new contrast agent to scan three patient groups; (i) heart disease caused by heart attacks, (ii) heart disease with abnormal thickening of the heart muscle, and (iii) heart disease where the heart becomes stretched and enlarged. Healthy volunteers will be scanned for comparison. The study will be carried out at the Royal Infirmary of Edinburgh. Adults between 18 and 65 with stable heart failure can be considered. Women who may be pregnant are unable to participate, as is anyone who has some types of metal in their body, as these people can't have an MRI scan safely. All participants will have 2 MRI scans lasting about an hour each, at least 2 days apart. Some participants will be have 4 MRI scans, over a longer time period. The investigators will also take some blood samples and record a tracing of the heart rhythm and will ensure there are no abnormal side-effects by telephone follow up. The investigators believe this new agent has potential to better measure disease in the heart, improve the ability to establish the cause of heart disease and help monitor the disease over time as well as guide future treatment for individual patients.
Electrophysiologic and Morphologic Assessment of the Substrate to Guide Implantation of Defibrillators...
Dilated CardiomyopathyPrimary Prevention of Sudden Cardiac Death1 moreWith the present study the investigators intend to identify the morphologic and electrophysiologic substrate markers of increased arrhythmic risk in patients with dilated cardiomyopathy undergoing implantation of a defibrillator for the primary prevention of sudden cardiac death. Moreover, the investigators also aim to identify if there is any electrophysiological substrate modification at the time of the first arrhythmic event in these patients. To this aim, the investigators will prospectively correlate electroanatomic mapping and cardiac magnetic resonance findings with arrhythmic events, in order to identify substrate markers of increased arrhythmic risk in patients with dilated cardiomyopathy, who are therefore more likely to benefit from a defibrillator implantation. Furthermore, electroanatomic mapping will be repeated at the time of the first arrhythmic event and compared with that at baseline, in order to evaluate any electrophysiological substrate changes.
Zinc Deficiency in Dilated Cardiomyopathy
Zinc DeficiencyThe aim of this study is to detect effect of oral zinc supplementation in pediatric patients with dilated cardiomyopathy.
Electrophysiological Phenotyping Of Patients at Risk of Ventricular Arrhythmia and Sudden Cardiac...
ArrhythmiaSudden Cardiac Death4 moreObesity, rheumatoid arthritis (RA) and gene-specific dilated cardiomyopathy (DCM) are common medical conditions. Small-scale studies have shown that these are associated with proarrhythmic changes on 12-lead electrocardiogram (ECG) and a higher risk of sudden cardiac death (SCD). However, these studies lack the deep electrophysiological phenotyping required to explain their observations. Electrocardiographic imaging (ECGi) is a non-invasive alternative to 12-lead ECG, by which epicardial potentials, electrograms and activation sequences can be recorded to study adverse electrophysiological modelling in greater depth and on a more focussed, subject-specific scale. Therefore, this study proposes to better define the risk of arrhythmia and understand the underlying adverse electrophysiological remodelling conferring this risk in three groups (obesity, RA and DCM). Firstly, data from two large, national repositories will be analysed to identify associations between routine clinical biomarkers and proarrhythmic 12-lead ECG parameters, to confirm adverse electrophysiological remodelling and a higher risk of arrhythmia. Secondly,ECGi will be performed before and after planned clinical intervention in obese and RA patients, and at baseline in titin-truncating variant (TTNtv)-positive and -negative DCM patients, to characterise the specific and potentially reversible conduction and repolarisation abnormalities that may underlie increased arrhythmic risk.
MRI Sequence and Imaging Protocol Development
CardiomyopathyHypertrophic5 moreThe purpose of this study is to develop imaging protocols when using cardiovascular magnetic resonance (CMR) to assess cardiac functions, morphology and tissue characterization. The National Heart Research Institute Singapore (NHRIS) houses two dedicated CMR scanners to support the numerous investigator initiated projects in patients with various cardiac pathologists. By optimizing novel CMR sequences used in these studies, scanning time can be shortened for patients with underlying cardiac diseases.