Active clinical trials for "Tachycardia"

We propose to use actigraphy (measured by activity watches) as a tool to quantify sleep disturbances in patients with orthostatic intolerance compared with healthy control subjects. In this pilot study, we will test the null hypothesis (Ho) that there are no differences in the sleep quality between patients with orthostatic intolerance and healthy control subjects.

The main objective of this study is to compare the time from randomization to the first recurrence of any ventricular tachycardia (VT) in patients undergoing VT ablation (for stable VTs) and substrate ablation (for unstable VTs) after an initial episode of stable VT and patients not undergoing ablation, with both groups under the protection of an ICD.

Interventional study in patients with ICD. Controlled, open intervention with exercise training. Assessment of changes in physiological and psychological parameters.

Ultra-high density mapping with multielectrode catheter may improve slow conduction channels identification in ventricular tachycardia substrate ablation procedures compared to conventional point by point mapping. This study compares the ability of both mapping catheters to detect slow conduction channels in areas of myocardial scar and their utility to assess substrate modification after ablation.

The MADIT-CRT trial is designed to determine if combined implantable cardiac defibrillator (ICD)-cardiac resynchronization therapy (CRT-D) will reduce the risk of mortality and heart failure (HF) events by approximately 25%, in subjects who are in New York Heart Association (NYHA) functional Class II with non-ischemic or ischemic cardiomyopathy and subjects who are in NYHA functional Class I with ischemic cardiomyopathy, left ventricular dysfunction (ejection fraction [EF] < or = 0.30), and prolonged intraventricular conduction (QRS duration > or = 130 ms).

The present standard of care for the management of unstable ventricular tachycardia (VT) in the setting of chronic coronary artery disease is the placement of an implantable cardioverter defibrillator (ICD) after the initial episode, and radiofrequency ablation and/or antiarrhythmic medication in the event of recurrences causing frequent ICD interventions. The primary purpose of this randomized study is the assessment of recurrences of unstable VT in patients who undergo ICD implantation plus substrate ablation after the initial episode compared to patients who only undergo ICD implantation. Thus the primary purpose is an improvement in the quality of life. A decrease in mortality is not a primary purpose of this study.

This observation study evaluates the safety and performance of UPT therapy in subjects during either an indicated ventricular tachycardia ablation procedure or an ICD implant procedure.

To evaluate the safety and efficacy of dexmedetomidine and compare this to a current technique commonly used at TGH for sedation in patients undergoing ablation procedures for atrial fibrillation (AF) and atrial flutter. The investigators hypothesise that dexmedetomidine will be at least equivalent to, or more so, in terms of effectiveness and safety, when compared to midazolam and remifentanil for sedation during ablation procedures.

The goal of this trial is to test the impact of a step-wise approach for catheter ablation of recurrent ventricular tachycardia, (irregular heart rhythms that originate in the bottom chambers of the heart), in patients with a previous heart attack for whom catheter ablation is clinically indicated.

This study is intended to develop a better method for stopping potentially lethal heart rhythms than currently available defibrillators. This new method, called Unpinning Termination Therapy (UPT), is hypothesized to be effective in stopping these dangerous heart rhythms at lower voltages and energy than current defibrillators. Consequently, UPT may improve survival, reduce patient pain from shocks, and lead to longer lasting and smaller implantable defibrillators.