View clinical trials related to Tachycardia.
Filter by:The purpose of this study is to see if people with Postural Tachycardia Syndrome (POTS) have different levels of certain chemicals in their blood than people who don't have POTS. This study will test whether the blood vessels of people with POTS will react differently to certain tests than people without POTS. The hypothesis of the study is: Patients with POTS will have vascular endothelial dysfunction compared with control subjects.
The purpose of this research study is to evaluate the safety and feasibility of the Impella 2.5 Circulatory Support System for use during mapping and ablation of ventricular tachycardia in the setting of Ventricular dysfunction.
The purpose of this study is to evaluate the effect of dexmedetomidine on hemodynamic responses during laryngoscopy and double lumen endotracheal intubation and assess the adverse effect related to complications of dexmedetomidine.
The primary objective is to determine whether, during a rapid sequence intubation by etomidate, and succinylcholine Sellick maneuver, the administration of remifentanil at 2 different dosages (0.5 and 1.0 microgram per kg body weight), reduces potentially dangerous reactional tachycardia.
Monophasic action potential (MAP) recording plays an important role in a more direct view of human myocardial electrophysiology under both physiological and pathological conditions. The MAP method represents a very useful tool for an electrophysiological research in cardiology. Its crucial importance lies in the fact that it enables the study of the action potential (AP) of myocardial cell in vivo and, therefore, the study of the dynamic relation of this potential with all the organism variables what can be particularly helpful in the case of arrhythmias. Hundred and fifty patients will be included to explore mapping capabilities in cardiac chambers in patients suffering from regular or fibrillating tachycardia's with the following inclusion plan: i) Atrial fibrillation at a total of 50 patients ii) Ventricular fibrillation or patients at high risk of sudden cardiac death at a total of 50 patients iii) Junctional tachycardia at a total of 50 patients. We will focus on cardiac activation (depolarization and repolarization) in this population.
Some patients are at risk for life-threatening fast heart rates. These can frequently be treated by using a catheter inside the heart to burn away the cells that create the fast heart rates. The purpose of this study is to image the nerves inside the heart of those patients. The investigators want to find out if abnormalities in the nervous system in the heart can help the physician to find the area that needs to be burnt away.
Catheter ablation has proven to be an effective treatment option in patients suffering from symptomatic persistent atrial fibrillation (AF). Catheter ablation consists of two major steps: (1) Isolation of pulmonary veins to abolish the trigger of atrial fibrillation and (2) modification of left atrial and eventually right atrial substrate by ablation of complex fractionated atrial electrograms (CFAE). CFAE are mainly found at the ostia of the pulmonary veins, around the left atrial appendage, at the mitral annulus and the septum. When ablating CFAE 40-65% of the patients show a regularization of AF to an atrial tachycardia (AT) that can be macro- or micro-reentrant (localized re-entry). Until now the significance of the AT is unclear. In the following study we examine the hypothesis that an ablation of AT occuring during CFAE ablation (group 1) significantly improves outcome defined as freedom of atrial arrhythmia (AF or AT) compared to patients that are cardioverted when AF has regularized to AT (group 2).
The main objective of this study is to demonstrate the clinical safety of a contact force sensing RF ablation catheter when used for the treatment of supraventricular tachycardia and atrial fibrillation. In addition, the study will characterize the use and value of contact force measurement during ablation, and the long term success (12 months) of the ablation procedure using this technology.
The investigators study will determine how often blood flow regulation abnormalities and abnormalities of sympathetic regulation produced by nitric oxide, angiotensin-II, and oxidative stress occur in POTS and the mechanism(s) of POTS in individual patients. Specific causes for POTS may vary from patient to patient. Patients will be compared to healthy control subjects. There is a treatment arm with a medication (losartan) that reduces the binding of angiotensin and increases NO. If the investigators know the specific biochemical mechanism the investigators may be able to offer further specific treatments to specific patients.
Ventricular tachycardia (VT) is an abnormal rapid heartbeat which occurs after a heart attack and can cause sudden death. Patients at risk of this rhythm disturbance usually receive an implantable cardioverter defibrillator (ICD) that can prevent death by returning the heart's rhythm back to normal by electrically stimulating the heart but in doing so gives the patient painful and debilitating shocks. The first ICD shock after implantation appears to be a powerful predictor of subsequent shock therapy as well as being a predictor of of increased mortality in patients with primary prevention ICDs. In patients who receive repeated shocks VT ablation is performed to 'burn' the abnormal area of the heart that causes the problem. However, it is often only performed as a last resort as it is technically challenging. We believe that performing VT ablation using the robotic system early after the first episode of VT after ICD implantation, may reduce the number of painful shocks received by the patient and possibly increase life expectancy and quality of life. 200 patients from 5 european countries will be recruited in a prospective, open, randomised trial. Eligible, consenting patients who have experienced their first episode of VT since ICD implantation, will be randomised in a 1:1 manner into treatment arms of either VT ablation or standard 'conventional' therapy and followed-up every 4 months over two years to assess the number of subsequent ICD shocks, hospitalisation, mortality and quality of life.