Active clinical trials for "Tachycardia"

To determine if the dietary N-3 class of polyunsaturated fatty acids (PUFAs) provided in the diet largely from marine fish oils would prevent fatal ventricular tachycardia (VT) or ventricular fibrillation (VF).

Subjects will be consented to wear the CoVa-2 monitoring system prior to (baseline), during, and after an Electrophysiology Procedure (EP). During this time, the system will measure the following parameters from subjects: heart rate (HR), Heart Rate Variability (HRV), respiration rate (RR), and Cardiac Output (CO). Data will be retrospectively analyzed to determine if the system effectively operates under these conditions, and can effectively monitor subjects and allow them to be discharged early from the hospital. Subjects will not be measured while transferred in and out of the operating room. Approximate sample size is 20 subjects.

Contextualization: Exercise is a common triggers of bronchospasm in patients with asthma and healthy subjects. To prevent these symptoms frequently they have to use Short-Acting Beta2-Agonists. However, the cardiovascular effects of salbutamol during and after exercise remain poorly known. Objective: To evaluate the effect of salbutamol on heart rate and blood pressure during exercise in patients with moderate or severe asthma and healthy individuals. Methods: A randomized, double-blind, crossover study will be conducted which 13 individuals with moderate or severe persistent asthma and 13 healthy individuals aged between 20 to 59 years. Patients will perform a maximal effort test on 2 nonconsecutive days, with either 400mcg Salbutamol or 4 placebo puffs. The order of use of placebo or salbutamol will be drawn. During the protocol, heart rate, blood pressure, perception of exertion and peak expiratory flow will be monitored.

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.

Patients requiring long term anticoagulation often undergo transition of their warfarin to heparin in anticipation of invasive surgical procedures such as pacemaker or ICD implantation. This may require inpatient hospitalization several days prior to and after the procedure, potentially increasing medical costs and patient inconvenience. Patients undergoing such a process are initiated on heparin while their INRs drift to normal levels. Immediately prior to surgery, heparin is discontinued and restarted several hours after the procedure. Unfortunately, this process has resulted in a high incidence of surgical wound hematomas and other bleeding complications often requiring longer periods of discontinued anticoagulation or repeat surgical exploration. Previous investigators have tried to reduce the incidence of wound hematomas by prolonging the time from surgical wound closure to the reinitiation of heparin. A small randomized trial demonstrated that there was no significant difference in the incidence of wound hematomas whether heparin was started 6 hours or 24 hours after surgery (J Am Coll Cardiology 2000;35:1915-8). This has led many investigators to perform pacemaker and ICD implantation without reversal of warfarin therapy. A recent retrospective observational study demonstrated that the incidence of wound hematomas in patients with an INR of 2.6 was no different than patients with an INR of 1.5 (PACE 2004;27:358-60). Furthermore, a more recent, larger retrospective observational study reported in abstract form at the recent Heart Rhythm Society Annual 2007 Scientific Meeting demonstrated that not only is performing pacemaker and ICD implantations safe without reversing warfarin anticoagulation, but the incidence of wound hematomas is significantly smaller as compared to the strategy of reversing warfarin and initiating periprocedural heparin. Given these findings, the hypothesis of this randomized study is that pacemaker and ICD implantation while fully anticoagulated on warfarin therapy is safe. Findings from this study will have significant implications on the clinical practice of pacemaker or ICD implantation in this patient population given that no randomized study on this subject has been performed to date.

This study investigates if the early detection and treatment of supraventricular arrhythmia (SVA) may help to prevent the progression of the arrhythmia and improve the clinical outcome. The primary endpoint investigates the delay to implement treatment in two groups of patients : Active group: Patients followed by telecardiology. Control group: Patients followed in the conventional manner. It is assumed that the delay to implement treatment will be higher in the Control group.

The purpose of this clinical study is to collect safety and performance data to support a demonstration of substantial equivalence of the Catheter Robotics Remote Catheter System to predicate devices when used to perform EP mapping of the right heart (atrium and ventricle).

The purpose of this study is to determine whether the ability of clinicians to receive and review information from patients implanted with a heart device over the internet (remote care) is comparable to patients who are seen in-office for routine visits to check the status of their device.

RIGHT is a randomized, prospective, two-arm study that will assess the differential efficacy of VITALITY 2 implantable cardioverter defibrillators (ICDs) using Rhythm ID™ versus selected Medtronic ICDs.

In this study, we aimed to evaluate atrial and ventricular function in supraventricular tachyarrhythmia patients before and 3 months after RFA using 2DSTE.