Active clinical trials for "Tachycardia"

The purpose of this study is to investigate how the electrical stimulation of a nerve in the skin of the earlobe (transcutaneous vagal nerve stimulation), alone or in combination with two medications (galantamine and pyridostigmine), affects the way the autonomic (involuntary) nervous system controls heart rhythm, symptoms on standing, and inflammatory markers in female patients with postural tachycardia syndrome (POTS). The study consists of 2 parts: a screening (1-2 study days), and 3 testing days. The study will take 5 days total and about 16 participants will be screened for the study. The investigators estimate 13 will be eligible to participate in all of the study days.

Pivotal Summary: The study is designed to demonstrate safety and efficacy of the Extravascular Implantable Cardioverter Defibrillator (EV ICD) System. Continued Access Summary: This study is designed to provide continued access to the Extravascular Implantable Cardioverter Defibrillator (EV ICD) System.

Atrioventricular nodal reentry tachycardia is best treated with catheter ablation aimed at disruption of conduction of the slow pathway. There are currently two possible options for this ablation: radiofrequency ablation and cryoablation. The first seems to result in superior success rate, however carries a small risk of collateral damage of the heart conduction system, specifically the atrioventricular (AV) node. Cryoablation seems less effective, but safer as AV nodal damage can be avoided. The aim of this study is to prospectively test possible improved efficcacy of cryoablation of the slow pathway with the use intraprocedural intracardiac echocardiography.

This study aims to evaluate the electrophysiological properties of the heart conduction system in patients with (increased risk of) ventricular tachyarrhythmias (VTA) and sudden cardiac arrest, and in a control cohort. The electrophysiological properties will be measured with the relatively new technique ECG-Imaging (ECGI). Moreover, clinical data of subjects will be gathered. By combining the data from the data gathering and the results of ECGI, the investigators hope to increase mechanistic understanding of and risk stratification for VTAs. The investigators aim to be able to identify patients at risk of an arrhythmic event, and aim for better treatment strategies in the future.

DNA Acetylation can be responsible for significant down-regulation of transcription of the Norepinephrine Transporter (NET). NET is an important clearance transporter that removes norepinephrine (NE) from sympathetic neuronal synapses. Very low levels of NET can "cause" Postural Tachycardia Syndrome (POTS) or make these patients more susceptible to certain medications. Quantified NET messenger RNA (mRNA) levels from a peripheral blood sample may be able to assess NET availability, which is simpler than older methods. This has not been validated against NET function. In this protocol, the investigators seek to assess whether these NET mRNA levels correlate with NET function. The investigators will assess the DHPG (NET dependent NE metabolite):NE ratio in POTS patients and control subjects from both plasma and urine samples.

Parasympathetic nervous system (PNS) is part of the body's autonomic nervous system(PNS) protects body against inflammation. Study shows that reduced PNS function activity is associated with persistent inflammation. Preliminary data from the studies shows, that post-COVID-19 POTS patients have reduced parasympathetic (PNS) function. Given that the PNS protects against inflammation, this clinical trial aims to prove that post-COVID-19 POTS is caused by reduced PNS activity, which in turn, contributes to persistent inflammation, orthostatic intolerance, and OI symptoms. The study will evaluate immune cell activation in post-COVID-19 POTS and patients with history of COVID-19 infection without sequelae and correlate this with the degree of decreased PNS activity.

VT ablation is a frequently performed intervention in patients with symptomatic ventricular tachycardia, electrical storm due to monomorphic VT and appropriate ICD shocks, primarily aiming at reducing the burden of complaints, and ICD shocks. The recommendations for its use were described in the ESC guideline for ventricular arrhythmias and the prevention of sudden cardiac death. To visualize the arrhythmogenic substrate leading to ventricular tachycardia complex mapping techniques are currently used in clinical routine, including conventional Point-by-Point mapping or Multielectrode Mapping. The latter is associated with shorter Mapping and overall procedure times, while maintaining the same primary endpoint of the procedure itself. The aim of this trial is to validate, whether the reduction of mapping and procedure time is associated with a comparable long-term outcome compared with conventional Point-by-Point mapping.

Among patients early following ST-segment (ST) elevation myocardial infarction, transcutaneous vagus nerve stimulation is associated with a reduce of the burden of premature ventricular contractions in the first 40 days post-myocardial infarction (MI). The above hypothesis will be tested with a randomized, prospective, parallel, single-blind clinical trial. The expected study duration is approximately 12 months from the time the first subject is enrolled (planned for June 2023) to the time of study's termination date (December 2024). Patient enrollment is planned to take place at two major centers in Greece. The researchers will obtain approval by the institutional review board (IRB).

Patients with ischemic ventricular tachycardia (VT) are frequently treated with radiofrequency catheter ablation. The efficacy of catheter ablation is limited for various reasons; one of those being incomplete myocardial and inhomogenous scar tissue damage due to suboptimal ablation lesions. The aim of our study is to reassess initially ablated endocardial areas in a repeated mapping procedure. Initial lesion parameters will be studied in areas with conduction recovery at repeated mapping procedure. Also, VT inducibility will be correlated to the extent and characteristics of areas with recovered conduction.

"Chang Gung ECG Abnormality Detection Software" is a is an artificial intelligence medical signal analysis software that detect whether patients have abnormal ECG signals of 14 diseases by static 12-lead ECG. The 14 diseases were Long QT syndrome Sinus bradycardia Sinus Tachycardia Premature atrial complexes Premature ventricular complexes Atrial Flutter, Right bundle branch block Left bundle branch block Left Ventricular hypertrophy Anterior wall Myocardial Infarction Septal wall Myocardial Infarction Lateral wall Myocardial Infarction Inferior wall Myocardial Infarction Posterior wall Myocardial Infarction The main purpose of this study is to verify whether "Chang Gung ECG Abnormality Detection Software" can correctly identify abnormal ECG signals among patients of 14 diseases. The interpretation standard is the consensus of 3 cardiologists. The results of the software analysis will be used to evaluate the performance of the primary and secondary evaluation indicators.