View clinical trials related to Tachycardia.
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This study aims to compare antiarrhythmic drug therapy with catheter ablation using the SmartTOUCH catheter (Biosense Webster Inc.) as treatment for patients with ventricular tachycardia and coronary artery disease
Inappropriate sinus tachycardia (IST) is an uncommon form of atrial tachycardia. The term "inappropriate" in medicine is commonly defined as a heart rate greater than 100 beats per minute at rest or with minimal physiological challenge. IST is characterized by an increased resting heart rate with an exaggerated response to exercise or stress. Yoga has been used extensively around the world as an alternative medicine approach in treating numerous chronic and debilitating diseases. Studies have been conducted in various countries to determine the benefits of Yoga as therapy for these chronic diseases. Several studies have confirmed that yoga can reduce anxiety and regulate the stress response. Studies in the past have shown that Yoga relieves stress, one of the most common triggers for the arrhythmia and increased heart rate in IST. Based on past studies we hypothesize that patients with IST might benefit by practicing yoga. Yoga may also help in better rate and rhythm control with yoga when employed in combination with usual medical arrangement.
Ventricular tachycardia (VT) is a morbid arrhythmia responsible for many sudden deaths and ICD shocks. Despite much progress in the treatment of arrhythmia, VT remains a therapeutic challenge. Most patients with VT have an implantable cardioverter defibrillator (ICD) for secondary prevention of sudden cardiac death, however, an ICD merely treats VT, it does not prevent VT. In patients with recurrent VT and ICD shocks, two strategies are available to decrease the burden of VT. The first is antiarrhythmic drugs, and the second is VT ablation. The aim of this study is to compare the efficacy of antiarrhythmic drugs and VT ablation guided by MRI. VT can sometimes be suppressed with antiarrhythmic medications, however, these are often ineffective, and carry a high burden of side effects. Many forms of VT can be cured by selective destruction of critical electrical pathways with catheter ablation. A major limitation in the ablation of VT, however, is the time required to localize scar tissue and important pathways for targeting of lesions. Magnetic resonance imaging can now obtain reliable images of scar location within the ventricles. Recent advances in electroanatomical mapping systems allow operators to import pre-acquired images into the mapping system. The aim of this study is to examine the feasibility of importing historic MRI scar maps of the ventricles into the electroanatomical system and using such images to guide catheter ablation, as compared to antiarrhythmic drug suppression of VT. We suspect that MRI guidance will be especially useful in patients with "unstable" VT, i.e. VT that causes an abrupt drop in blood pressure, and thus cannot be maintained in the electrophysiology (EP) lab for mapping and entertainment purposes. Patients referred for VT ablation have ICDs. Through previously completed animal work (Circulation 2004; 110(5): 475-82) and a human trial (2006 Sep 19;114(12):1277-84) we have demonstrated the safety of MRI in the setting of pacemakers and implantable defibrillators using appropriate precautions. Through careful device programming and using MRI sequences with limited energy exposure (specific absorption rate < 2 W/kg) we will study the pre procedural myocardial anatomy of patients enrolled into this study. The primary endpoint will be lack of VT documented by implantable defibrillator (when present) interrogation or Holter monitoring 6 months post ablation. The secondary endpoints will be comparison of inducible arrhythmia at the end of the procedure, procedure time, comparison of endocardial voltage mapping to scar on delayed enhancement MRI images, and complications in each study arm.
Cardiac arrest or sustained VT (ventricular tachycardia) in patients with heart disease is best treated with an ICD (implantable cardioverter defibrillator). However, the ICD alone is not appropriate therapy for patients with frequent VT episodes. In fact frequent shocks for VT may predict a poorer prognosis. Anti-arrhythmic drugs are co-administered with ICDs in up to 50% of patients to prevent VT episodes, but antiarrhythmic drugs may have harmful effects. Thus improved drugs to prevent VT without interfering with ICD function are needed. Recent data including our own suggest that clonidine may be a new therapy to prevent ICD shocks. It may act centrally on sympathetic outflow and peripherally and selectively on cardiac Purkinje, to suppress and control VT occurring in patients. Our purpose is to test the hypothesis that clonidine reduces frequent VT better than beta blocker in patients with ICDs. After informed consent patients will be randomized in a single blind fashion to either clonidine or metoprolol given three times per day. Other prescribed drugs may be adjusted to promote toleration of the study drug. ICD interrogations of episodes of VT will be the primary endpoint. Device based NIPS (non-invasive programmed stimulation) testing in a subset of these patients will allow mechanistic understanding of the clonidine effect. All of the procedural techniques are in place as performed clinically; preliminary data are given showing feasibility of the project.
This is a prospective study to evaluating the ability of the PD2i Cardiac Analyzer to predict the risk of serious heart rhythm abnormalities in high-risk patients that do not already have an Implantable Cardioverter Defibrillator.