View clinical trials related to Right Bundle-Branch Block.
Filter by:Cardiac electrical mapping is an important tool that allows doctors to study the electrical activity of the heart in detail. Electrical mapping systems used in clinical practice are time consuming, invasive and very costly. Ultra-high frequency electrocardiography is a novel non-invasive cardiac mapping system. Ultra-high frequency electrocardiography (UHF-ECG) can be performed in 10-15 minutes without any risk or discomfort to patients. The aim of this study is to refine this mapping system, verify it against invasive mapping and develop software to bring this novel system into routine clinical use including predicting which patients will respond to cardiac resynchronisation therapy.
The aim of this study is to compare the effectiveness of multiple modalities of cardiac resynchronisation therapy using high precision acute electrical and haemodynamic measurements.These modalities include biventricular pacing and conduction system pacing utilising His bundle and left bundle pacing. Conduction system pacing is a more physiological form of pacing. The study hypothesises that this will produce more effective cardiac resynchronisation.
Heart failure (HF) affects 5 million Americans and is responsible for more health-care expenditure than any other medical diagnosis. Approximately half of all HF patients have electrocardiographic prolongation of the QRS interval and ventricular dyssynchrony, a perturbation of the normal pattern of ventricular contraction that reduces the efficiency of ventricular work. Ventricular dyssynchrony is directly responsible for worsening HF symptomatology in this subset of patients. Resynchronization of ventricular contraction is usually achieved through simultaneous pacing of the left and right ventricles using a biventricular (BiV) pacemaker or implantable cardioverter-defibrillator. Clinical trial evidence supporting the use of BiV pacing in patients with prolonged QRS duration was obtained almost exclusively in patients with a left bundle-branch block (LBBB) electrocardiographic pattern. Recent evidence suggests that resynchronization of ventricular contraction in patients with LBBB can be obtained by univentricular left ventricular pacing with equal or superior clinical benefits compared to BiV pacing. Animal studies suggest that ventricular resynchronization can be obtained in subjects with right bundle-branch block (RBBB) through univentricular right ventricular pacing. No clinical trial evidence exists to support the use of BiV pacing in patients with RBBB. Thousands of patients with symptomatic HF and RBBB currently have univentricular ICDs in place for the prevention of sudden cardiac death. Most of these devices are currently programmed to avoid RV pacing. We aim to determine if ventricular resynchronization delivered through univentricular RV pacing improves symptoms in patients with RBBB and moderate to severe HF who have previously undergone BiV ICD implantation for symptomatic heart failure. We further aim to determine if ventricular resynchronization improves myocardial performance and ventricular geometry as detected by echocardiographic measures and quality of life for patients with HF and RBBB. We hypothesize that RV univentricular pacing delivered with an atrio-ventricular interval that maximizes ventricular synchrony is equivalent to BiV pacing for improvement in cardiac performance, HF symptoms, and positive ventricular remodeling in patients with HF and RBBB.