Active clinical trials for "Tachycardia"

The primary objective of this study is to demonstrate the superiority of at least 1 dose of intranasal (IN) MSP-2017 (Etripamil) over placebo in terminating PSVT induced in an electrophysiology (EP) laboratory.

The broad, long-term objective of this project is to evaluate the therapeutic value of vein of Marshall (VOM) ethanol infusion when added to catheter ablation of atrial fibrillation (AF). AF is the most common sustained arrhythmia in adults, and it is a leading cause of stroke, disability and increased mortality. Catheter ablation - pulmonary vein (PV) antral isolation (PVAI)- can lead to cure, but is best suited for paroxysmal AF, in which ectopic beats arising from the pulmonary veins were shown to initiate AF. PVAI success is lower in persistent AF, in which the role of the cardiac autonomic system, particularly the intrinsic cardiac ganglia, is being increasingly recognized. Expanding the ablation lesions to include greater areas the left atrial (LA) anatomy marginally improves outcomes, but also leads to increases in procedural complexity and duration, need of repeat procedures, and complications such as atrial flutters, particularly perimitral flutter (PMF). The investigators have developed a technique to perform rapid ablation of atrial tissues in AF using ethanol infusion in the vein of Marshall (VOM), and have shown: 1) Effective, rapid and safe tissue ablation of LA tissue neighboring the LA ridge and left inferior PV; 2) Regional LA vagal denervation by reaching the intrinsic cardiac ganglia; and 3) Facilitation of cure of PMF by ablating most of the mitral isthmus. The investigators propose to evaluate outcomes differences yielded by VOM ethanol when added to conventional PVAI. The specific aims are: #1.To assesses the impact of VOM ethanol infusion in procedure success when added to de novo catheter ablation of persistent AF. The investigators will randomize patients with persistent AF undergoing a first AF ablation to standard PVAI vs. a combined VOM ethanol infusion plus PVAI (VOM-PV) #2. To assess the impact of VOM ethanol infusion added to repeat catheter ablation of recurrent AF after a failed ablation. Patients undergoing a repeat procedure for persistent AF after a failed PVAI will be randomized to either PVAI or VOM-PV as their repeat procedure. End points will include freedom from symptomatic or electrocardiographic AF after 12-15 months.

Stimulants and drugs are often associated with cardiac effects. Caffeine, a therapeutic xanthine, has been described as a sympathomimetic and has shown to have stimulatory effects on the heart. Patients with symptomatic cardiac arrhythmias are generally informed by their physician to stop or significantly reduce caffeine intake. However, in spite of numerous reports that have reviewed the cardiac effects of caffeine, it remains unclear to what extent this stimulant may be detrimental, and what subgroups of patients may be most vulnerable. The investigators propose to evaluate the effects of caffeine in patients with previously diagnosed cardiac arrhythmias. The results of our report will provide important new information for physicians and patients regarding the effects of caffeine on symptomatic cardiac arrhythmias.

The purpose of the study is to assess the effectiveness and safety of a new device called an Intramural Needle Ablation Catheter (INA catheter). The INA catheter is used for locating and ablating ventricular arrhythmias that have failed standard radiofrequency ablation. This approach is desirable because some people have ventricular arrhythmias that originate deep within the heart muscle where it is not abolished by ablation with standard catheters. The investigators seek to determine whether the INA catheter can potentially help people who have ventricular arrhythmias that have failed standard radiofrequency ablation. The investigators also want to determine if it is likely to be safe, without excessive side effects.

The Postural Tachycardia-Syndrome (POTS) is a form of autonomic dysregulation, typically accompanied by symptoms of orthostatic intolerance (OI). OI is defined by the inability to tolerate the upright position and is improved by lying down. POTS is considered a syndrome that may include a number of several disorders. Symptoms should be persistent for at least 6 months to reach a diagnosis. It is characterized by a sustained heart rate (HR) increment of 30 beats/min or more within 10 min of standing or head-up tilt (HUT) in adults, in the absence of orthostatic hypotension and with the presence of symptoms of OI. In children and adolescents a diagnosis requests a HR increment of at least 40 beats/min. The increment in HR when moving to an upright posture is often a response to a reduction in venous return, causing excessive blood pooling in the lower limbs. The symptoms present in POTS vary greatly. Typical symptoms are lightheadedness, dizziness, blurred vision, mental clouding ("brain fog") or cognitive dysfunction. Other symptoms may present as palpitations or chest pain. Additional symptoms consist of postural headaches, nausea, sleep disturbances, fatigue and gastrointestinal dysfunction. The manifestation of symptoms in POTS varies in severity, frequency and combination, resulting in POTS being a very heterogenous and subjective disorder. Symptoms can be severe and often make simple daily activities difficult to an extent that compromises the patients quality of life. Typically symptoms exacerbate in the mornings, after physical activity, after eating and during menstruation. This study objective is to examine the occurrence, mechanisms and causes of impaired attention in POTS as well as to test the effect of acute water ingestion for attention in POTS. The investigators therefore conduct a study including patients with POTS and healthy volunteers. All participants will receive a dossier of five self-assessment questionnaires after giving informed consent. Clinical examination includes 2 HUT-tests while standing for 15 minutes, conventional measuring of blood pressure, continuous recording of NIRS signals during testing, determination of pupil size, the diameter of the optic nerve and Neuropsychological testing (Test of Attentional Performance, mobility version" (TAP-M), Go/NoGo Test, Divided Attention Test)

Evaluate the operation of the Implantable Subcutaneous String Defibrillator (ISSD) system in patients who require an Implantable Cardioverter Defibrillator (ICD) using an emulator.

Phase I/II study of 4-D Navigated Non-invasive radiosurgical ablation of ventricular tachycardia (NIRA-VT).

Myalgic encephalomyelitis/Chronic fatigue syndrome (ME/CFS), otherwise known as Chronic fatigue syndrome (CFS) or myalgic encephalomyelitis (ME), is an under-recognized disorder whose cause is not yet understood. Suggested theories behind the pathophysiology of this condition include autoimmune causes, an inciting viral illness, and a dysfunctional autonomic nervous system caused by a small fiber polyneuropathy. Symptoms include fatigue, cognitive impairments, gastrointestinal changes, exertional dyspnea, and post-exertional malaise. The latter two symptoms are caused in part by abnormal cardiopulmonary hemodynamics during exercise thought to be due to a small fiber polyneuropathy. This manifests as low biventricular filling pressures throughout exercise seen in patients undergoing an invasive cardiopulmonary exercise test (iCPET) along with small nerve fiber atrophy seen on skin biopsy. After diagnosis, patients are often treated with pyridostigmine (off-label use of this medication) to enhance cholinergic stimulation of norepinephrine release at the post-ganglionic synapse. This is thought to improve venoconstriction at the site of exercising muscles, leading to improved return of blood to the heart and increasing filling of the heart to more appropriate levels during peak exercise. Retrospective studies have shown that noninvasive measurements of exercise capacity, such as oxygen uptake, end-tidal carbon dioxide, and ventilatory efficiency, improve after treatment with pyridostigmine. To date, there are no studies that assess invasive hemodynamics after pyridostigmine administration. It is estimated that four million people suffer from ME/CFS worldwide, a number that is thought to be a gross underestimate of disease prevalence. However, despite its potential for debilitating symptoms, loss of productivity, and worldwide burden, the pathophysiology behind ME/CFS remains unknown and its treatment unclear. By evaluating the exercise response to cholinergic stimulation, this study will shed further light on the link between the autonomic nervous system and cardiopulmonary hemodynamics, potentially leading to new therapeutic targets.

The objective of this clinical investigation is to evaluate: the safety and efficacy of the CyberHeart System, CardioPlan™ Software and Laptop, in treating patients with refractory ventricular tachycardia (VT) using the CyberKnife® Radiosurgical System. The CyberHeart System performance with respect to the ability to contour myocardial targets that are transferred to the Multi-plan® Treatment Planning Software of the CyberKnife® system for the production and delivery of a safe radiosurgical treatment plan. Cardiac radiosurgery is a minimally-non invasive, painless, procedure. Tissue ablation can be accomplished precisely.

In this pilot study, the investigator will test the usefulness of gabapentin in treating some of the symptoms associated with POTS. Gabapentin is FDA-approved to treat epilepsy and nerve pain and works by reducing excessive activity in the nervous system. This medication has also been shown to be effective in reducing bowel discomfort in patients with irritable bowel syndrome, sleeplessness, and possibly migraine headache. The investigator has observed positive results when prescribing gabapentin off-label to alleviate photosensitivity and headaches in POTS patients. The aim of this pilot study is to better quantify what the investigator has seen and evaluate whether it merits further study in a larger group.