[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-studies-list:{\"conditionNormalized\":\"postural-tachycardia-syndrome\",\"overallStatus\":[\"RECRUITING\",\"AVAILABLE\",\"NOT_YET_RECRUITING\"],\"orderBy\":\"LastUpdateSubmitDate:desc\",\"size\":25,\"offset\":0}":3,"health-study-condition:postural-tachycardia-syndrome":25},{"pageToken":4,"total":5,"offset":6,"count":5,"results":7},null,9,0,[8,42,68,95,118,141,167,193,219],{"id":9,"slug":10,"hasResults":11,"nctId":12,"briefTitle":13,"officialTitle":14,"acronym":4,"eligibilityCriteria":15,"healthyVolunteers":11,"sex":16,"minAge":4,"maxAge":4,"enrollmentInfo":17,"targetDuration":20,"studyType":21,"phases":4,"briefSummary":22,"conditions":23,"keywords":26,"overallStatus":29,"whyStopped":4,"lastUpdateSubmitDate":30,"lastUpdatePostDateStruct":31,"startDateStruct":34,"completionDateStruct":36,"leadSponsor":38,"locationsCount":41},"100447530","inappropriate-sinus-tachycardia-registry-100447530",false,"NCT05107635","Inappropriate Sinus Tachycardia Registry","A Multicenter Patient Registry for Outcomes of Inappropriate Sinus Tachycardia and Postural Orthostatic Tachycardia Syndrome Treatment","Inclusion Criteria:\n\n1. Subject is scheduled to undergo or has undergone a procedure to treat IST or POTS using one or more AtriCure devices.\n2. Subject is willing to provide written informed consent (defined as legally effective, documented confirmation of a subject's voluntary agreement to participate in this Registry) or authorization per institution and geographical requirements\n\nExclusion Criteria:\n\n1. Subject is enrolled in a concurrent study that may impact treatment outcome of IST or POTS.\n2. Subject with exclusion criteria required by FDA or local governance","ALL",{"count":18,"type":19},500,"ESTIMATED","12 Months","OBSERVATIONAL","The primary objective of this registry is to capture real-world safety and performance data on AtriCure devices used to ablate cardiac tissue when treating Inappropriate Sinus Tachycardia (IST) or Postural Tachycardia Syndrome (POTS). This is a retrospective and prospective, multicenter, US\u002FOUS, observational data registry.",[24,25],"Inappropriate Sinus Tachycardia","Postural Tachycardia Syndrome",[24,27,28],"Postural Tachycardia Syndrome;","Sinus Node Sparing Hybrid Procedure","RECRUITING","2026-06-25",{"date":32,"type":33},"2026-06-26","ACTUAL",{"date":35,"type":33},"2022-03-01",{"date":37,"type":19},"2027-01",{"name":39,"class":40},"AtriCure, Inc.","INDUSTRY",12,{"id":43,"slug":44,"hasResults":11,"nctId":45,"briefTitle":46,"officialTitle":46,"acronym":4,"eligibilityCriteria":47,"healthyVolunteers":11,"sex":16,"minAge":48,"maxAge":49,"enrollmentInfo":50,"targetDuration":4,"studyType":51,"phases":52,"briefSummary":54,"conditions":55,"keywords":4,"overallStatus":56,"whyStopped":4,"lastUpdateSubmitDate":57,"lastUpdatePostDateStruct":58,"startDateStruct":60,"completionDateStruct":62,"leadSponsor":64,"locationsCount":67},"100486745","the-impact-of-improved-vagal-function-on-periaqueductal-gray-connectivity-100486745","NCT05618067","The Impact of Improved Vagal Function on Periaqueductal Gray Connectivity","Inclusion Criteria:\n\n* Age 18-50 years\n* Diagnosis of POTS, orthostatic intolerance (with or without syncope), syncope, or near-syncope\n* Can speak and read in English\n* Upcoming new patient VCU Comprehensive Autonomics Center clinic visit scheduled at least 1 week in the future\n\nExclusion Criteria:\n\n* Inflammatory arthritis, connective tissue or auto-immune disorder\n* Any chronic neurological disorder besides POTS, orthostatic intolerance (with or without syncope), syncope, or near-syncope\n* Patients who have already had a new patient clinic visit where they were exposed to breathing exercise education\n* Evidence of unstable medical disorder, such as kidney (rising creatinine, or end-stage renal failure) or liver impairment (rising AST or ALT, or end-stage with coagulopathy), poorly controlled significant cardiovascular (CHF), respiratory, endocrine (diabetes - A1c \\> 9 - or untreated thyroid dysfunction) or uncontrolled psychiatric illness (such as untreated depression, psychosis, etc.)\n* Neuropathy, central nervous system disorder (e.g., Cerebral palsy, developmental delay, seizure disorder, MS, stroke, etc.)\n* Treatment with a drug or medical device within the previous 30 days that has not received regulatory approval\n* Use of hormones (except insulin, thyroid replacement or oral contraceptives, which will be carefully documented)\n* Current substance or alcohol abuse\n* Any major surgical intervention with general anesthesia in the last 60 days and minor procedure, such as tooth extraction, endoscopy, etc., with local or conscious sedation within 7 days\n* Any on-going or pending medical, health or disability related litigation, or current pursuit of disability\n* Any condition that in the judgment of the investigator would interfere with the patient's ability to provide informed consent, comply with study instructions, place the patient at increased risk, or which would clearly confound the interpretation of the study results (specific reason will be documented)\n* Chronic use of narcotics for pain\n* Claustrophobia or any metal hardware that may interfere with MRI\n* Investigators and study staff","18 Years","50 Years",{"count":41,"type":19},"INTERVENTIONAL",[53],"NA","This study is being to see if participating in breathing exercise training and practicing this training will help with Postural tachycardia syndrome (POTS). The information may help doctors to learn more about how the different parts of people's brains communicate.",[25],"NOT_YET_RECRUITING","2026-06-08",{"date":59,"type":33},"2026-06-09",{"date":61,"type":19},"2026-07",{"date":63,"type":19},"2028-12",{"name":65,"class":66},"Virginia Commonwealth University","OTHER",1,{"id":69,"slug":70,"hasResults":11,"nctId":71,"briefTitle":72,"officialTitle":72,"acronym":4,"eligibilityCriteria":73,"healthyVolunteers":11,"sex":16,"minAge":48,"maxAge":74,"enrollmentInfo":75,"targetDuration":4,"studyType":51,"phases":77,"briefSummary":78,"conditions":79,"keywords":81,"overallStatus":29,"whyStopped":4,"lastUpdateSubmitDate":86,"lastUpdatePostDateStruct":87,"startDateStruct":89,"completionDateStruct":91,"leadSponsor":93,"locationsCount":67},"100383378","hypercapnia-and-orthostatic-tolerance-in-postural-orthostatic-tachycardia-syndrome-100383378","NCT04271878","Hypercapnia and Orthostatic Tolerance in Postural Orthostatic Tachycardia Syndrome","Inclusion Criteria:\n\n* Physician diagnosis of Postural Tachycardia Syndrome (POTS)\n* Age 18-60 years\n* Male and Female\n* Non - smokers.\n* Able and willing to provide informed consent.\n* Ability to travel to Libin Cardiovascular Institute of Alberta Autonomic Testing Lab at the University of Calgary, Calgary, AB.\n\nExclusion Criteria:\n\n* Overt cause for postural tachycardia, i.e., acute dehydration\n* Participants with somatization or severe anxiety symptoms will be excluded\n* Pregnant\n* Inability to tolerate mask for the duration of the study\n* Subjects who require portable oxygen at rest or with exercise\n* Subjects with chronic heart failure or severe pulmonary disease who are unable to climb one flight of stairs due to shortness of breath.\n* Other factors which in the investigator's opinion would prevent the participant from completing the protocol, including poor compliance during previous studies.","60 Years",{"count":76,"type":19},26,[53],"The mechanism behind postural orthostatic tachycardia syndrome (POTS) involves many causes including a sympathetic nervous system problem. Blood gases, like carbon dioxide (CO2), have an important effect on sympathetic activation.\n\nThe purpose of this research study is to determine if higher CO2 levels have any effect in lowering heart rate and reducing POTS symptoms when upright\u002Fstanding. The investigators are also searching for the ideal CO2 concentration to achieve the most effective response",[25,80],"Orthostatic Intolerance",[82,83,84,85],"postural tachycardia","autonomic","orthostatic intolerance","dysautonomia","2026-04-30",{"date":88,"type":33},"2026-05-07",{"date":90,"type":33},"2022-02-02",{"date":92,"type":19},"2030-12-31",{"name":94,"class":66},"University of Calgary",{"id":96,"slug":97,"hasResults":11,"nctId":98,"briefTitle":99,"officialTitle":100,"acronym":4,"eligibilityCriteria":101,"healthyVolunteers":102,"sex":16,"minAge":48,"maxAge":74,"enrollmentInfo":103,"targetDuration":4,"studyType":21,"phases":4,"briefSummary":105,"conditions":106,"keywords":107,"overallStatus":29,"whyStopped":4,"lastUpdateSubmitDate":111,"lastUpdatePostDateStruct":112,"startDateStruct":114,"completionDateStruct":116,"leadSponsor":117,"locationsCount":67},"100260783","pots-adrenergic-ab-cihr-aims-12-100260783","NCT02673996","POTS Adrenergic Ab (CIHR Aims #1&2)","The Pathophysiological Role of Adrenergic Antibodies in Postural Tachycardia Syndrome (Aims #1&2)","Inclusion Criteria:\n\n* Patients who have been previously diagnosed with POTS\n* Control subjects (patients not diagnosed with POTS)\n* Age between 18 - 60 years\n* Males and Females (Give that \\>80% of POTS patients are female, we will attempt to enroll a similar percentage of female control subjects)\n* Able and willing to provide consent\n\nExclusion Criteria:\n\n* Smokers\n* Overt cause for postural tachycardia, i.e., acute dehydration\n* Significant cardiovascular, pulmonary, hepatic, or hematological disease by history or prior testing\n* Highly trained athletes\n* Subjects with somatization or severe anxiety symptoms will be excluded\n* Use of drospirenone (a spironolactone analogue) containing oral contraceptive agent\n* Hypertension defined as supine resting BP\\>145\u002F95 mmHg off medications or needing antihypertensive medication\n* Other factors which in the investigator's opinion would prevent the participant from completing the protocol, including poor compliance during previous studies or an unpredictable schedule\n* Unable to give informed consent",true,{"count":104,"type":19},125,"Objective: In this pilot study, we will test the hypothesis that patients with POTS (age 18-60 years) will have a higher percentage of functional antibodies to adrenergic receptors compared with control subjects without POTS.",[25],[108,109,110,83],"antibody","autoimmune","adrenergic","2026-04-29",{"date":113,"type":33},"2026-05-05",{"date":115,"type":33},"2016-01",{"date":92,"type":19},{"name":94,"class":66},{"id":119,"slug":120,"hasResults":11,"nctId":121,"briefTitle":122,"officialTitle":123,"acronym":4,"eligibilityCriteria":124,"healthyVolunteers":102,"sex":125,"minAge":126,"maxAge":127,"enrollmentInfo":128,"targetDuration":4,"studyType":51,"phases":130,"briefSummary":131,"conditions":132,"keywords":4,"overallStatus":29,"whyStopped":4,"lastUpdateSubmitDate":133,"lastUpdatePostDateStruct":134,"startDateStruct":136,"completionDateStruct":138,"leadSponsor":140,"locationsCount":67},"100486744","periaqueductal-gray-vagus-nerve-interface-malfunction-explain-the-natural-history-with-its-numerous-co-morbidities-100486744","NCT05618054","Periaqueductal Gray-vagus Nerve Interface Malfunction Explain the Natural History With Its Numerous Co-morbidities?","Pediatric POTS: Does a Periaqueductal Gray-vagus Nerve Interface Malfunction Explain the Natural History With Its Numerous Co-morbidities?","Inclusion Criteria:\n\n* Females 12-21 years old\n* Able to communicate and provide consent\u002Fassent\n* English speaking\n* Diagnosed with POTS (POTS will be defined standardly as a symptomatic ≥ 40 bpm rise in heart rate without a drop in blood pressure and with symptoms of orthostatic intolerance clinically)\n* Age-matched healthy control subjects: no POTS or other neurological disorders\n\nExclusion Criteria:\n\n* Inflammatory arthritis, connective tissue or auto-immune disorder\n* Any chronic neurological disorder besides POTS\n* Evidence of unstable medical disorder, such as kidney (rising creatinine, or end-stage renal failure) or liver impairment (rising AST or ALT, or end-stage with coagulopathy), poorly controlled significant cardiovascular (CHF), respiratory, endocrine (diabetes - A1c \\> 9 - or untreated thyroid dysfunction) or uncontrolled psychiatric illness (such as untreated depression, psychosis, etc.)\n* Neuropathy, central nervous system disorder (e.g., Cerebral palsy, developmental delay, seizure disorder, MS, stroke, etc.)\n* Treatment with a drug or medical device within the previous 30 days that has not received regulatory approval\n* Use of hormones (except insulin, thyroid replacement or oral contraceptives, which will be carefully documented)\n* Current substance or alcohol abuse\n* Any major surgical intervention with general anesthesia in the last 60 days and minor procedure, such as tooth extraction, endoscopy, etc., with local or conscious sedation within 7 days\n* Any on-going or pending medical, health or disability related litigation, or current pursuit of disability\n* Any condition that in the judgment of the investigator would interfere with the patient's ability to provide informed consent, comply with study instructions, place the patient at increased risk, or which would clearly confound the interpretation of the study results (specific reason will be documented)\n* Chronic use of narcotics for pain\n* Claustrophobia or any metal hardware that may interfere with MRI\n* Investigators and study staff","FEMALE","12 Years","21 Years",{"count":129,"type":19},36,[53],"This study is being conducted to see how people with Postural tachycardia syndrome (POTS) make sense of the things they see. The information may help doctors to learn more about how the different parts of people's brains communicate.",[25],"2026-04-20",{"date":135,"type":33},"2026-04-21",{"date":137,"type":33},"2023-03-06",{"date":139,"type":19},"2026-12",{"name":65,"class":66},{"id":142,"slug":143,"hasResults":11,"nctId":144,"briefTitle":145,"officialTitle":146,"acronym":4,"eligibilityCriteria":147,"healthyVolunteers":11,"sex":16,"minAge":148,"maxAge":149,"enrollmentInfo":150,"targetDuration":4,"studyType":51,"phases":152,"briefSummary":154,"conditions":155,"keywords":156,"overallStatus":29,"whyStopped":4,"lastUpdateSubmitDate":158,"lastUpdatePostDateStruct":159,"startDateStruct":161,"completionDateStruct":163,"leadSponsor":165,"locationsCount":67},"100088389","phase-2-a-study-of-pyridostigmine-in-postural-tachycardia-syndrome-100088389","NCT00409435","A Study of Pyridostigmine in Postural Tachycardia Syndrome","Double-Blind, Placebo-Controlled Study of Pyridostigmine in Postural Tachycardia Syndrome","Inclusion Criteria:\n\nDiagnosis of postural tachycardia syndrome using the following criteria:\n\n* Orthostatic heart rate increment greater than or equal to 30 beats per minute (bpm) within 5 minutes of head-up tilt.\n* Symptoms of orthostatic intolerance. These include weakness, lightheadedness, blurred vision, nausea, palpitations, and difficulty with concentration and thinking.\n\nBoth criteria must be fulfilled.\n\nExclusion Criteria:\n\n* Pregnant or lactating women\n* Presence of failure of other organ systems or systemic illness that could affect autonomic function or the patient's ability to cooperate with the study\n* Hypothyroidism or hyperthyroidism\n* Clinically significant coronary artery disease\n* Medications that could interfere with autonomic testing\n* Previous treatment with pyridostigmine for POTS. Patients must not have taken pyridostigmine in the past month","15 Years","55 Years",{"count":151,"type":19},50,[153],"PHASE2","This is a 3-day study comparing pyridostigmine versus placebo in the treatment of postural tachycardia syndrome (POTS). The researchers expect pyridostigmine to improve tachycardia and stabilize blood pressure.",[25],[157],"Postural tachycardia syndrome (POTS)","2026-03-03",{"date":160,"type":33},"2026-03-05",{"date":162,"type":4},"2006-10",{"date":164,"type":19},"2027-02",{"name":166,"class":66},"Mayo Clinic",{"id":168,"slug":169,"hasResults":11,"nctId":170,"briefTitle":171,"officialTitle":172,"acronym":4,"eligibilityCriteria":173,"healthyVolunteers":11,"sex":16,"minAge":48,"maxAge":4,"enrollmentInfo":174,"targetDuration":4,"studyType":51,"phases":176,"briefSummary":177,"conditions":178,"keywords":179,"overallStatus":56,"whyStopped":4,"lastUpdateSubmitDate":183,"lastUpdatePostDateStruct":184,"startDateStruct":186,"completionDateStruct":188,"leadSponsor":190,"locationsCount":192},"100589380","ultrasound-guided-stellate-ganglion-block-in-postural-tachycardia-syndrome-100589380","NCT06953661","Ultrasound Guided Stellate Ganglion Block in Postural Tachycardia Syndrome","Ultrasound Guided Stellate Ganglion Block in Postural Tachycardia Syndrome: A Randomized Double Blind Sham Placebo-controlled Pilot Study","Inclusion Criteria:\n\n* Adult patients (\\>18 years of age) diagnosed with POTS\n* Ability to provide informed consent\n* Ability to comply with 3 follow up visits\n* English speaking and capable of signing informed consent and complying with protocol requirements\n\nExclusion Criteria:\n\n* Allergy to local anesthetics\n* Severe coagulopathy\n* History of or currently being treated for clinically significant ongoing cardiac arrhythmia, heart failure, myocarditis, pulmonary embolism requiring anticoagulation, pulmonary fibrosis or other pulmonary diagnosis that in the investigator's opinion may contribute to symptoms of POTS\n* Inability to maintain a stable medication regiment for the duration of the study",{"count":175,"type":19},20,[53],"This single-center study aims to evaluate both immediate and long-term outcomes of stellate ganglion block (SGB) in a cohort of rigorously phenotyped patients with Postural Tachycardia Syndrome (POTS). By assessing the effects of SGB, this study seeks to determine its viability as an intervention for symptom control in POTS.",[25],[180,181,182],"stellate ganglion block","regional anesthesia","nerve block","2025-10-10",{"date":185,"type":33},"2025-10-15",{"date":187,"type":19},"2025-10-13",{"date":189,"type":19},"2026-11",{"name":191,"class":66},"Stanford University",2,{"id":194,"slug":195,"hasResults":11,"nctId":196,"briefTitle":197,"officialTitle":198,"acronym":199,"eligibilityCriteria":200,"healthyVolunteers":11,"sex":16,"minAge":48,"maxAge":201,"enrollmentInfo":202,"targetDuration":204,"studyType":21,"phases":4,"briefSummary":205,"conditions":206,"keywords":4,"overallStatus":29,"whyStopped":4,"lastUpdateSubmitDate":210,"lastUpdatePostDateStruct":211,"startDateStruct":213,"completionDateStruct":215,"leadSponsor":217,"locationsCount":67},"100386354","autonomic-small-fiber-neuropathy-and-ehlers-danlos-syndromes---prospective-study-and-registry-100386354","NCT04310644","Autonomic Small Fiber Neuropathy and Ehlers Danlos Syndromes - Prospective Study and Registry","Autonomic Neuropathy and Its Pathophysiology in Autoimmune Autonomic Neuropathies, Postural Orthostatic Tachycardia Syndrome and Ehlers Danlos Syndromes: Peripheral Autonomic Small Fiber Neuropathy or Central Autonomic Failure? Validation of the Malmö POTS Score and a Better Diagnosis of POTS in Patientes With Autnomic Failure (VaGeMAPS-3-step-Diag)","ProANS","Inclusion Criteria:\n\n* autonomic neuropathy\n* Postural orthostatic tachycardia syndrome\n* hypermobile or classical Ehlers Danlos syndromes\n* Chronic fatigue syndrome, mast cell activation syndrome and\u002For PostCOVID\n* healty controls\n* between 18-80 years\n* in patients: diagnosis and clinical testing in our outpatient clinic\n* German speaking\n\nExclusion Criteria:\n\n* pregnancy\n* Pacemaker or Deep brain Stimulation\n* sensory or motor Polyneuropathy\n* neurodegenerative disease","80 Years",{"count":203,"type":19},200,"5 Years","We examine patients with different autonomic neuropathies and Ehlers Danlos syndromes compared to healthy controls at three different points over time (baseline, after 3 months and after 1.5 years) to gain knowledge about the course of this disease and understand its pathophysiology, with a focus on Small Fiber neuropathy. Moreover we will validate the german version of the Malmö POTS Score and establish an easy diagnostic scheme for patients in outpatient care.",[207,208,209,25],"Autonomic Neuropathy","Ehlers-Danlos Syndrome Hypermobility Type","Small Fiber Neuropathy","2025-02-03",{"date":212,"type":33},"2025-02-04",{"date":214,"type":33},"2019-09-15",{"date":216,"type":19},"2029-09-15",{"name":218,"class":66},"RWTH Aachen University",{"id":220,"slug":221,"hasResults":11,"nctId":222,"briefTitle":223,"officialTitle":224,"acronym":4,"eligibilityCriteria":225,"healthyVolunteers":11,"sex":16,"minAge":48,"maxAge":74,"enrollmentInfo":226,"targetDuration":4,"studyType":51,"phases":227,"briefSummary":228,"conditions":229,"keywords":4,"overallStatus":29,"whyStopped":4,"lastUpdateSubmitDate":230,"lastUpdatePostDateStruct":231,"startDateStruct":233,"completionDateStruct":235,"leadSponsor":237,"locationsCount":67},"100376804","phase-2-crossover-study-of-propranolol-vs-ivabradine-in-pots-100376804","NCT04186286","Crossover Study of Propranolol vs Ivabradine in POTS","A Randomized Crossover Study of Propranolol Versus Ivabradine in Postural Tachycardia Syndrome (POTS)","Inclusion Criteria:\n\n* Diagnosis of Postural Tachycardia Syndrome\n* Age between 18-60 years\n* Men and women are eligible\n* Able and willing to provide informed consent\n\nExclusion Criteria:\n\n* Seated resting heart rate \\\u003C 70 bpm in the absence of rate-lowering medications\n* Supine blood pressure \\\u003C 90\u002F60 mmHg\n* Overt cause for postural tachycardia, i.e., acute dehydration, prolonged bed rest\n* Presence of underlying structural heart disease including:\n* Valvular disease (i.e. moderate or greater valvular stenosis or regurgitation)\n* History of heart failure\n* Greater than mild left ventricular systolic impairment\n* Hypertrophic cardiomyopathy\n* Known coronary artery disease or prior myocardial infarction\n* History of tachyarrhythmias including:\n* Supraventricular tachycardia, atrial tachycardia, atrial fibrillation \u002F flutter\n* Ventricular tachyarrhythmias\n* Pre-existing long QT interval (e.g. known congenital long QT syndrome, or QT interval \\>500 ms)\n* History of sick sinus syndrome or high degree AV block\n* Presence of a pacemaker, implantable cardioverter defibrillator or cardiac resynchronization therapy device\n* Diabetes mellitus or history of hypoglycemic episodes\n* History of bronchospasm or uncontrolled asthma\n* Pregnant (by history or serum test) or breast-feeding\n* Inability to safely withdraw from existing beta-blockers or ivabradine prior to the study day\n* Concomitant use of class I and III antiarrhythmic agents, or non-dihydropyridine calcium channel blockers\n* Concomitant use of strong cytochrome P450 3A4 (CYP 3A4) inhibitors\n* Severe hepatic impairment\n* Any contraindication to propranolol or ivabradine not specifically listed above as per the product monographs.\n* Unable to give informed consent",{"count":175,"type":19},[153],"1.0 BACKGROUND Postural tachycardia syndrome (POTS) is a disorder of chronic orthostatic intolerance characterized by symptoms of palpitations, lightheadedness, chest discomfort, shortness of breath, blurred vision, and mental clouding. These symptoms occur during standing and are associated with a marked increase in heart rate (HR) in the absence of hypotension, which typically resolve when sitting or lying down. Most importantly, POTS is associated with a very poor quality of life and significant functional disability. POTS patients commonly experience mental clouding (\"brain fog\") even while lying down or seated, which poses significant limitations to daily activities .\n\nUnfortunately, there is a relative paucity in the literature assessing therapies for POTS patients. Given that excessive tachycardia on standing is a fundamental component of this syndrome, a handful of studies have evaluated medications that reduce HR. Ivabradine is newer drug that is a selective If channel blocker that reduces HR without affecting other cardiovascular functions.\n\n2.0 RATIONALE \u002F STUDY PURPOSE The investigators propose to compare the efficacy of propranolol and ivabradine on HR response to standing, and symptom burden in patients with POTS.\n\n3.0 Study Design This will be a single-center double-blind placebo-controlled randomized crossover trial conducted in patients with POTS to compare effects of (1) oral ivabradine 5 mg bid plus placebo BID (to fill out a QID schedule); (2) oral propranolol 10 mg qid; and (3) oral placebo qid in POTS patients. After a baseline screening assessment following a washout period of 7 days, participants will be randomized to start with a 4-week course of either ivabradine, propranolol or placebo. The other two treatments will be given in separate 4-week courses with a 7-day washout period between phases, with each participant acting as his or her own control. At the end of each 4-week phase, participants will complete the symptom-rating and HRQOL questionnaires, and also undergo tilt table testing to assess the change in HR at 10 min with head up tilt.\n\nParticipants will undergo POTS testing at baseline and at the end of each 4-week treatment course. This will involve a total of 4 separate study visits.",[25],"2024-05-08",{"date":232,"type":33},"2024-05-09",{"date":234,"type":33},"2021-02-01",{"date":236,"type":19},"2026-12-31",{"name":94,"class":66}]