Adrenocorticotropic Hormone Stimulation in Postural Orthostatic Tachycardia Syndrome (POTS)
Postural Tachycardia SyndromeThis study is to determine different chemical levels in the blood during a low salt diet. This study will compare normal volunteers to those with Postural Tachycardia Syndrome (POTS)
Peripheral Dopamine in Postural Tachycardia Syndrome
Postural Tachycardia SyndromeOrthostatic IntoleranceThe purpose of the proposed research is to determine how changes in kidney dopamine (DA) activity influence urinary sodium excretion. We will decrease DA activity in the kidney by inhibiting DA synthesis via carbidopa administration. We want to compare findings in normal volunteers and in patients with postural tachycardia syndrome (POTS). We will test the null hypothesis (Ho) that the effects of oral carbidopa administration on urinary sodium excretion will not differ between patients with POTS and healthy volunteers.
Master Study of the Acticor/Rivacor ICDs/CRT-Ds and the Plexa ProMRI S DX Lead
Heart FailureTachyarrhythmiaPost-Market Clinical Follow-up of the new Cor Family ICDs/CRT-Ds (Acticor, Rivacor) and the new Plexa ProMRI S DX right ventricular lead to provide post-market data and supporting evidence for the clinical safety and performance of the devices.
Heart Rate Variability and Cognitive Load on Image-Based Virtual Reality Instructional Design in...
Cognitive Function 1Social5 moreThis study aims to compare heart rate variation, cognitive load, and learning outcomes of novel image-based virtual reality with traditional video in learning for otolaryngology. Half of participants will receive image-based virtual reality learning, while the other half will receive video-based learning.
Remote Self-training Program for Patients With Postural Orthostatic Tachycardia Syndrome
Postural Orthostatic Tachycardia SyndromeThe purpose of this research is to evaluate if a hybrid semi-supervised remote exercise training program can reduce symptoms and improve quality of life and physical fitness in individuals with postural orthostatic tachycardia syndrome (POTS) and determine if this program is more effective than current standard of care.
Sensing and Defibrillation With a Commercially Available ICD Coupled With a Parasternal Extravascular...
Ventricular ArrhythmiaVentricular Tachycardia1 moreThe SECURE EV Study is a prospective, multi-center, single-arm study without concurrent or historical controls. The objectives of the study are 1) to characterize safety of the AtaCor EV-ICD Lead up to 90 days post-implant, and 2) to characterize sensing and conversion of induced VF up to 90 days post-implant.
Understanding Outcomes With the EMBLEM™ S-ICD in Primary Prevention Patients With Low Ejection Fraction...
Ventricular FibrillationVentricular Tachycardia1 moreThis study assesses the 18-month incidence of inappropriate shocks in subjects implanted with the EMBLEM Subcutaneous Implantable Defibrillator (S-ICD) for primary prevention of sudden cardiac death. Devices are to be programmed with zone cutoffs at 200 bpm and 250 bmp in order to mimic the programming settings for transvenous ICDs in the MADIT RIT study. The incidence of inappropriate S-ICD shocks will be compared to the incidence of inappropriate shocks observed in the MADIT RIT study.
Percutaneous Hemodynamic Support With Impella 2.5 During Scar-related Ventricular Tachycardia Ablation...
Ventricular TachycardiaThe 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.
Dietary Salt in Postural Tachycardia Syndrome
Postural Orthostatic Tachycardia SyndromePatients with POTS may not adequately expand their plasma volume in response to a high-sodium (Na+) diet. Mechanisms involved in the regulation of plasma volume, such as the renin-angiotensin-aldosterone system and renal dopamine, may be impaired in POTS and may respond inappropriately to changes in dietary sodium.The purpose of this study is to determine (1) whether a high dietary sodium level appropriately expands plasma volume in POTS; (2) whether plasma renin activity and aldosterone are modified appropriately by changes in dietary sodium in POTS; and (3) whether patients with POTS have improvements in their orthostatic tachycardia and symptoms as a result of a high dietary sodium level.
An Assessment of Dual Site Left Ventricular Endocardial Pacing
Atrial FibrillationVentricular Tachycardia1 moreWe are investigating ways to help patients with heart failure, which is caused by damaged hearts which function less well, and cause symptoms of breathlessness, fatigue, lack of energy and swelling. Cardiac Resynchronisation Therapy (CRT) pacemakers are used to improve the pumping function of the main heart chamber in certain suitable people with heart failure. CRT requires a pacemaker with 2 wires, one placed inside the right heart chamber and one normally placed on the outside of the left heart chamber. These two wires act together to re-time the coordination of the heartbeat, which is known to improve heart function. The investigators are assessing whether they might be able to improve heart function even more by placing two wires on the inside of the left heart chamber, rather than one around the outside. The investigators wish to assess whether: Using two wires within the left side of the heart gives a greater increase in heart function than one. It is possible to choose the best spot inside of the heart by measuring the pattern of the heart beat. Is it possible to use a different type of heart monitor placed outside the body instead of a monitor wire inside the heart to assess improvement in heart function? They are investigating this in people with hearts that beat less effectively than normal.