View clinical trials related to Tachycardia.
Filter by:This clinical investigation is a device-based open, prospective, multicenter two-arm randomized trial, comparing patients who are treated in the slow VT zone versus patients who are not treated in that zone. The device intended to be used is the OVATIOTM CRT model 6750 but future generation of Sorin Group/ ELA Medical devices may be used provided they are CE marked. Ethics committees and health authorities will be informed prior to any use of a newer device if applicable. All patients will have a 3-zone detection configuration programmed. The slow VT zone will be defined by programming the detection parameters as follows: - Slow VT detection rate: 100 bpm (or if the resting rate is higher than 80 bpm, we recommend to adjust this parameter to: resting rate + 30 bpm) - VT detection rate: 150 bpm PARAD+ will be the first choice for SVT/ST and VT discrimination in the VT zones. The Fast VT and VF limits are left to investigator's judgment. Therapy on VT, fast VT and VF are also left to the investigator's judgment. Patients will be randomized at implant to have the slow VT zone programmed as a monitoring zone (monitoring arm) or to have therapies programmed within the slow VT zone (therapy arm). The randomization table will be generated by Sorin Group/ELA Medical.
Retrospectively review the charts of all children who had heart rate variability, deep breathing test, valsalva maneuver, tilt table test, thermoregulatory sweat testing, quantitative sudomotor axon reflex test (QSART) completed and were cared for at Children's Hospital of Wisconsin.
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.
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.
The purpose of this evaluation is to assess the acceptance level of specific programming recommendations based on the patient's clinical needs and primary indications when using the feature 'Indications Based Programming' (IBP) available in the ZOOMVIEW Software Application for the TELIGEN DR / VR and COGNIS family of devices compared to daily life programming chosen by physicians.
The investigators performed a prophylactic peroperative linear lesions connecting the tricuspid annulus with a right atriotomy and the atriotomy with the inferior caval vein to prevent atrial flutter on 15 consecutive adult patients undergoing surgery for congenital heart disease. Conduction time between electrodes placed on both sides of the lesions is measured on the second postoperative day. Coronary angiography and electrophysiology study using an electroanatomic mapping system to assess conduction across the line are performed three month after the operation.
The study evaluates 3 different populations: It is an open, randomized, parallel-group study comparing the effectiveness of intravenous (iv) ajmaline with currently used antiarrhythmic drugs in the acute treatment of : 1. recent-onset atrial fibrillation versus iv flecainide 2. sustained monomorphous ventricular tachycardia versus iv procainamide The study also evaluates in an open, randomized, crossover study, the use of iv ajmaline versus iv flecainide in the diagnosis of Brugada syndrome
Chronic beta-adrenoceptor blockade is known to improve outcome of high risk patients whereas amelioration of autonomic activity was demonstrated to be a major cause of outcome improvement. Therefore, perioperative beta-adrenoceptor blockade is recommended in patients with Revised Cardiac Risk Index score of three or greater. The investigators hypothesise that preoperative intravenous beta-adrenoceptor blockade for treatment of hypertension and/or tachycardia improves autonomic activity reflected by increase of Total Power of Heart Rate Variability. Material and Methods: After IRB approval 20 patients scheduled for elective cardiac surgery were included into the study. Routine medication was continued throughout the study as recommended by the guidelines. HRV (TP and Low to High Frequency ratio (LF/HF) reflecting sympathetic to parasympathetic balance) was analysed prior to induction of general anesthesia and beta-adrenoceptor blockade in all patients (Baseline). Patients were assigned by their baseline hemodynamics. Patients with hypertension (systolic blood pressure > 140mmHg or diastolic blood pressure > 90mmHg) or tachycardia (heart rate > 80bpm) were assigned to group BETA-BLOCK. In this group metoprolol-boli (2mg) were administered intravenously in stepwise manner until hemodynamic values decreased to normal. Total dosage was recorded. After normalisation of hemodynamics, second HRV analysis was performed (Intervention). Normotensive and normocardic patients were assigned to group CONTROL. No intervention was performed. Statistics: Mann Whitney U test for comparison between groups and between events Baseline and Intervention within group BETA-BLOCK, p<0.05.
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 purpose of the proposed research is to determine how changes in kidney dopamine (DA) activity influence urinary sodium excretion. We will decrease DA activity in the kidney by inhibiting DA synthesis via carbidopa administration. We want to compare findings in normal volunteers and in patients with postural tachycardia syndrome (POTS). We will test the null hypothesis (Ho) that the effects of oral carbidopa administration on urinary sodium excretion will not differ between patients with POTS and healthy volunteers.