View clinical trials related to Tachycardia.
Filter by:Despite significant advances in the management of ventricular arrhythmias through the use of ICD therapy, AADs, and catheter-based ablation strategies, considerable challenges remain. The optimal method for the prevention of recurrent VT following catheter ablation remains unclear. RSDN may be an effective tool for preventing ventricular arrhythmias, and associated ICD therapies, by reducing central sympathetic tone, catecholamine levels, and the renin-angiotensin- aldosterone system and promoting ventricular remodeling. Although RSDN has been shown to reduce the recurrence of VT in a case report of 2 patients suffering from electrical storm, to date no large prospective randomized study has evaluated the impact of RSDN in the prevention of recurrent VT in patients following catheter ablation of VT with ischemic or non-ischemic ventricular dysfunction. This study will specifically evaluate the safety and efficacy of adjunctive RSDN in the prevention of ICD therapy in patients with ischemic or non-ischemic ventricular dysfunction who are to receive a catheter-based VT ablation.
The objective of this study is to gather data to establish the chronic safety, performance and effectiveness of the RELIANCE 4-FRONT™ Passive Fixation Defibrillation Leads.
Ventricular tachycardia is one of the commonest cause of sudden death in chronic chagas disease. As most ventricular tachycardias originate from scar in patients with heart disease, catheter ablation is an important step in patient treatment. Identification of fibrosis prior to ablation of sustained ventricular tachycardia (SVT) might reduce the time of anesthesia, procedure time, radiation exposure and possibly the risk of complications. Knowledge of arrhythmia circuit within scar allows planning strategies for each procedure. Condreanu et al. stablished that voltages inferior to 6.52 mV (unipolar) and 1.54mV (bipolar) are useful tools in detecting scar during electroanatomic mapping. Accuracy, however when compared to magnetic resonance imaging is limited due to difficulties in maintaining good contact between ablation catheter and ventricular wall. Contact force catheters might help increase accuracy of voltage mapping because they allow detection of poor contact areas. Although the threshold for identification of scar in ischemic and non ischemic patients during electroanatomical mapping is already known, this parameters still lacking for chronic chagasic individuals. A marked qualitative histological difference between these fibrous scars supports the hypothesis that voltage scar in chagasics might be different. Catheter ablation contact with endo and epicardial surface is an important issue when ablating arrhythmias. Conventional catheter ablation is not equipped with sensors capable of detecting degree of contact with the target. To our knowledge, the literature lacks information in regard to late lesions produced by a known contact force pressure "in vivo". The pattern of electrical activation in these patients and their relationship with local coronary veins for resynchronization likely to approach through the coronary sinus can be useful in defining chagasic that can benefit from resynchronization. 1. Compare endocardial and epicardial impedance and voltage using CARTO 3 with fibrosis on 3T MRI 2. Correlate areas of late activation within scar during activating mapping in sinus rhythm with different signal intensity in 3T MRI 3. Evaluate the influence of contact pressure during application of radiofrequency in making fibrosis analyzed 30 days after the procedure using a 3T MRI. 4. Assess the site of latest left ventricular activation in sinus rhythm and correlate with the coronary veins location
Obtain baseline clinical outcome data (Stage 1) upon which to base a subsequent study (Stage 2) of the Model 106 VNS implantable pulse generator
Prolonged Collagen/Epinephrine - closure time (CEPI-CT) indicates platelet dysfunction in CKD patients taking antiplatelet agent. The synthetic vasopressin derivative, Desmopressin (DDAVP) shortens the prolonged bleeding time and improves platelet dysfunction measured by in vitro closure time: CEPI-CT in uremic patients. Desmopressin also antagonizes the in vitro platelet dysfunction induced by GPIIb/IIIa inhibitors, clopidogrel and aspirin. The investigators designed a prospective study to evaluate the effect of desmopressin on platelet function, as measured by in vitro collagen/epinephrine - closure time, in uremic patients who were taking antiplatelet drugs.
The study is designed to confirm safety and efficacy of the SD01 ICD (implantable cardioverter-defibrillator) lead.
The primary hypothesis is that an ICD shock may be predicted days in advance by a combined score derived from different data obtainable from the ICD
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
Postural orthostatic tachycardia syndrome (POTS) is a common cause of orthostatic intolerance in adolescents and adults. Compression stockings are commonly recommended as a treatment modality for POTS, but the effects of abdominal and lower extremity compression during tilt table testing have not been measured in adolescent patients. The aims of our study are to compare heart-rate changes and symptom onset during tilt table testing (a) with and without abdomen/lower extremity compression and (b) with abdominal compression only versus lower extremity compression only. During phase 1, 20 adolescents with POTS will undergo up to 10 minutes of tilt without compression (trial #1), a repeat study of up to 10 minutes with full compression (trial #2), and a third study without compression up to 10 minutes (trial #3). Compression will be performed using the non-inflatable Zoex anti-shock garment. During study phase 2, an additional 20 adolescent POTS patients will undergo up to 10 minutes of tilt without compression (trial #1), a repeat study of up to 10 minutes with abdominal compression only [n=10] or lower extremity compression only [n=10] (trial #2), and a third study repeated without compression up to 10 minutes (trial #3). To limit compression to the abdomen only, we will use the Zoex garment strap numbers 4 and 5 (thigh and abdomen) without straps 1-3 (lower extremities). For lower extremity-only compression, we will use Zoex garment straps 1-4 (lower extremity and thigh) without strap 5. Data collected will include mean and peak heart rates and timing of symptoms with each trial. A paired-samples t-test will be used to compare mean heart rates between trials for each study phase. Hazard analyses will be used to assess time-based endpoints.
Vasovagal Syncope (simple postural faint) is the most common cause of acute loss of consciousness. Postural tachycardia syndrome(POTS) is the most common chronic form of postural lightheadedness. Together they afflict many Americans, mostly young women, who are prevented from gainful employ or school attendance. The underlying mechanism is not known. Our past work suggests that a simple molecule, nitric oxide, acts to subvert normal blood flow controls causing blood to pool in the gut when standing. Our proposal will show the mechanism behind this problem and will indicate effective medical treatments. Patients will be compared to healthy control subjects.