Paced Electrogram Feature Analysis (PEFA) for Ablation Targeting in Ischaemic Ventricular Tachycardia...
Ischemic Ventricular Tachycardia (VT)Canadian multicentre prospective cohort study of 40 patients with ischaemic heart disease and therapy from an implantable cardioverter defibrillator (ICD).
Cardiovascular Autonomic and Immune Mechanism of Post COVID-19 Tachycardia Syndrome
Post-acute COVID-19 SyndromePostural Tachycardia Syndrome (POTS)2 moreThe term post-acute COVID-19 syndrome or Long COVID is a disabling syndrome that persists beyond the 3-month convalescence period after COVID-19 infections. This syndrome affects mostly women (~80%), present with chronic tachycardia and Orthostatic intolerance symptoms without any identifiable cause. In addition, non-specific symptoms such as fatigue, headache, and "brain fog", commonly described in POTS patients are also present in this novel condition, recently named post-COVID-19 tachycardia syndrome, POTS variant. Reduced Vagal activity and unresolved inflammation is post-COVID-19 POTS is hypothesized as the cause of Long COVID
Effects of Individual Tailored Physical Exercise in Patients With POTS After COVID-19 - a Randomized...
Postural Orthostatic Tachycardia SyndromeCOVID-192 moreCovid-19 has the potential to affect physical, cognitive and psychological functions in multiple ways. It has been clear that a significant proportion of patients with Covid-19 develop long-term symptoms. The term post COVID-19 condition (defined by WHO) is used to describe the wide range of prolonged symptoms following the infection. Patients may need specialized rehabilitation to be able to meet the complex symptoms and problems that may arise. A more specific syndrome that seems to occur more frequently than expected in the group of non-hospitalized patients with post COVID-19 condition is the postural orthostatic tachycardia syndrome (POTS). A randomized controlled design will be used to evaluate the effects of individual tailored physical exercise in patients with POTS after Covid-19. Participants: Adults (>18 years) with post COVID-19 condition and diagnosed with POTS (n=60) will be included. Exclusion criteria: known pregnancy, cancer, already ongoing individual physical exercise (specific for POTS), or not able to perform measurements and/or intervention. Procedure and outcomes: The primary outcomes are objectively measured time in upright position and health-related quality of life. Secondary outcomes are: physical activity, physical capacity, work ability and disease specific symptoms measured with tests and questionnaires. Prior to randomization baseline measurements will be performed, aswell as after 16 weeks, 6 months and 12 months. Intervention: Participants randomized to intervention will receive standard care and undergo a individually designed physical exercise program during 16 weeks, supervised and guided by a physiotherapist. The intervention will consist of different exercises to enhance muscle strength and endurance. Progression will be according to a program (based on previous feasibility studie) but should be halted if post exertional malaise (PEM) or other problems occur. Controls: Participants randomized to control will receive standard care during 16 weeks. Measurements of both groups (control and intervention) will be repeated after completion of a period of 16 weeks.
Splanchnic Venous Capacitance in Postural Tachycardia Syndrome
Postural Tachycardia Syndrome (POTS)Postural tachycardia syndrome (POTS) affects ≈3 million young people, characterized by chronic presyncopal symptoms characterized by dizziness, lightheadedness, and orthostatic tachycardia that occur while standing. Across-sectional survey found that 25% of these patients complains that meals rich in carbohydrates are among the factors that further exacerbate POTS's symptoms and cause a myriad of gastrointestinal symptoms. The splanchnic circulation is the largest blood volume reservoir of the human body, storing ≈25% of the total blood volume and contributing to sudden, and large, fluctuations in the stroke volume (SV). These orthostatic changes in systemic hemodynamics are particularly magnified after meals, due to increased blood volume sequestration triggered by the release of gastrointestinal peptides with vasodilatory properties. The purpose of this study is to determine if the worsening orthostatic tachycardia and symptoms after glucose ingestion in POTS patients are due to a greater increase in splanchnic venous capacitance and excessive blood pooling on standing as compare to Healthy controls
Targeted Potassium Levels for Prevention of ICD Therapy
Ventricular Arrhythmias and Cardiac ArrestImplantable Defibrillator User4 moreThis study evaluates whether a rigorously controlled high-normal level of serum-potassium (4.5-5.0 mEq/L) using dietary recommendations, potassium supplements and mineralocorticoid receptor antagonists will results in a lower incidence of cardiac arrhythmias in patients with an ICD. Patients will be randomized to this treatment or a control arm, where patients will receive usual guideline recommended follow-up.
Peri-Procedural Transmural Electrophysiological (EP) Imaging of Scar-Related Ventricular Tachycardia...
Ventricular TachycardiaMyocardial InfarctionVentricular tachycardia (VT) contributes to over 350,000 sudden deaths each year in the US. Malignant VTs involve an electrical "short circuit" in the heart, formed by narrow channels of surviving tissue inside myocardial scar. An important treatment is to use catheter ablation to "block" the channel that forms the circuit. Effective ablation requires imaging guidance to visualize the VT circuit relative to scar structures in 3D. Unfortunately, with conventional catheter mapping, up to 90% of the VT circuits are too short-lived to be mapped. For the 10% "mappable" VTs, their data are only available during ablation and limited to one ventricular surface. This inadequacy of functional VT data largely limits the knowledge about scar-related VT and ablation strategies, and reduces the ability of clinicians to identify ablation targets and assess ablation outcome. The central hypothesis of this proposal is that functional VT data, integrated with CT or MRI scar data in 3D, can improve VT ablation efficacy with pre-procedural identification of ablation targets and post-procedural mechanistic elucidation of ablation failure. This research builds on the rapidly increasing clinical interest in electrocardiographic imaging (ECGi), an emerging technique that obtains cardiac electrical activity through inverse reconstructions from ECGs. The specific objective is to push the boundary of ECGi to provide - as a conjunction to intra-procedural catheter mapping - pre-ablation and post-ablation imaging of functional VT circuits integrated with 3D scar structure.
Etripamil Nasal Spray in Patients With Paroxysmal Supraventricular Tachycardia
Paroxysmal Supraventricular TachycardiaThis Open Label Extension study will enable eligible patients with Paroxysmal Supraventricular Tachycardia (PSVT) who have previously participated in a Milestone Pharmaceuticals clinical trial of etripamil NS for PSVT, to access continued treatment with etripamil NS, Patients who experienced any significant safety issues during participation period in a previous clinical trial of etripamil NS, as per Investigator's assessment , are excluded. This study will be conducted by Investigators who previously participated in a Milestone Pharmaceuticals clinical trial and are trained on the use of etripamil NS.
Dexmedetomidine and Magnesium Sulfate in Preventing Junctional Ectopic Tachycardia After Pediatric...
Post Operative Arrythmiato study the prophylactic effect of magnesium sulfate , dexmedetomidine or their combination in reduction the incidence of JETS postoperative
Phenotyping Mitochondrial and Immune Dysfunction in POTS With Targeted Clinical Intervention.
Postural Tachycardia SyndromeThe mechanisms underlying POTS are not well understood. Though heterogeneous in nature, patients often present with symptoms that include fatigue, orthostatic lightheadedness and tachycardia, "brain fog", shortness of breath, and sleep disruption. The central mediator that links observations in disease entities similar to POTS is energy use and balance driven by mitochondrial health. Mitochondrial dysfunction (i.e. respiration defects, reactive oxygen species (ROS) generation, and structural abnormalities) are hallmarks of currently defined syndromes that resemble POTS symptomatology. Many patients with POTS have underlying immune system dysfunction, which, when treated, may improve the patient's overall health. Though autoimmunity has been demonstrated in POTS, overall immune dysregulation may be broader and include immune cell exhaustion and persistent inflammatory cytokine responses. Immune dysfunction including cellular exhaustion and persistent inflammation has been linked to mitochondrial function. Therefore, we hypothesize that a unifying feature of POTS results from latent or continued mitochondrial/immune dysfunction which then impacts multi-organ energy imbalance and immune homeostasis. Understanding and targeting mitochondria utilizing established, novel, and directed approaches including time-restricted eating (TRE) will help to unravel common etiologies and help us to better diagnose, manage, and treat POTS.
Stereotactic Arrhythmia Radioablation for Ventricular Tachycardia (StAR-VT)
Ventricular TachycardiaArrhythmia2 moreIn 2017 a novel treatment approach to a series of 5 patients with refractory VT was introduced, using ablative radiation with a stereotactic body radiation therapy (SBRT) technique to arrhythmogenic scar regions defined by noninvasive cardiac mapping. More recently, Robinson et al. reported on the results of their Electrophysiology-Guided Noninvasive Cardiac Radioablation for Ventricular Tachycardia (ENCORE-VT) trial, also using a similar SBRT technique in a series of 17 patients with refractory VT. Both studies report a marked reduction in VT burden, a decrease in antiarrhythmic drug use, and an improvement in quality of life. Since then, numerous other centres have detailed their initial experience with this technique. These initial results suggest that this new treatment paradigm has the potential to improve morbidity and mortality for patients suffering from treatment-refractory VT by means of a minimally invasive technique, but requires further validation for widespread use. The appropriate dose for therapeutic effect of this new treatment is not well established as only a single dose prescription of 25 Gy in 1 fraction has been described with benefit. In this phase 2 trial, the investigators plan on expanding the experience with this technique but also by contributing to understanding the relationship between dose-effect relationship through a dose de-escalation stratification, to 20 Gy in 1 fraction, with the goal of minimizing possible adverse events and radiation dose to surrounding healthy tissue while maintaining a clinical benefit.