How is PoTS diagnosed?
What is PoTS?
PoTS is a form of autonomic nervous system dysfunction that primarily affects heart rate regulation upon standing. It is defined by a sustained heart rate increase of 30 beats per minute (bpm) or more (or over 120 bpm total) within 10 minutes of standing or during head-up tilt testing, without a corresponding drop in blood pressure. In adolescents, the diagnostic threshold is a rise of 40 bpm or more.
Patients with PoTS typically experience symptoms such as:
● Light-headedness or dizziness
● Brain fog
● Exercise intolerance
● Fatigue
● Syncope or pre-syncope
● Gastrointestinal issues
These symptoms can significantly impair quality of life, interfere with employment and education, and often mimic anxiety disorders—contributing to diagnostic delays.
Dysautonomia and its relevance
PoTS falls under the umbrella of dysautonomia, a broader category of disorders affecting the autonomic nervous system. This can also include conditions like neurocardiogenic syncope and orthostatic hypotension. The underlying pathophysiology of PoTS can vary and includes:
● Neuropathic PoTS: involving partial denervation of sympathetic fibres
● Hyperadrenergic PoTS: associated with elevated plasma norepinephrine
● Hypovolaemic PoTS: linked to reduced blood volume
● Secondary PoTS: occurring with conditions like Ehlers-Danlos syndrome or post-viral syndromes
How is PoTS diagnosed?
A formal diagnosis of PoTS involves:
● Active stand test or head-up tilt test with continuous heart rate and blood pressure monitoring
● Clinical history and symptom scoring (e.g. COMPASS-31)
● Autonomic function testing, if available, to rule out other dysautonomic conditions
Ruling out PoTS mimics
Before confirming a diagnosis of PoTS, it is essential to exclude alternative or coexisting conditions that can mimic its presentation. These include:
● Cardiac arrhythmias such as atrial tachycardias or inappropriate sinus tachycardia, best identified using Holter monitoring or implantable loop recorders
● Structural cardiac conditions, including valvular disease or cardiomyopathies, assessed via echocardiography
● Endocrine abnormalities, such as adrenal disorders or thyroid dysfunction, evaluated through targeted blood tests
At our Aberdeen clinic, we provide access to comprehensive cardiac diagnostics and specialist endocrine testing to ensure that key differential diagnoses are ruled out prior to treatment. This thorough approach ensures accurate diagnosis and guides appropriate therapy.
Treatment of PoTS: A multi-modal approach
There is no one-size-fits-all treatment for PoTS. Management requires a tailored, often trial-and-error approach that includes both non-pharmacological and pharmacological strategies.
Non-pharmacological interventions
These form the cornerstone of PoTS management:
● Increasing fluid intake and salt supplementation
● Compression garments (waist-high stockings)
● Tilt training or graduated physical reconditioning programmes
● Avoidance of triggers (e.g. prolonged standing, heat)
● Sleeping with head of bed elevated
These strategies are endorsed by PoTS UK and NHS resources as first-line interventions.
Pharmacological therapy
Drug treatments are generally off-label and should only be initiated by experienced clinicians. Options include:
● Beta-blockers (e.g. propranolol, bisoprolol)
● Ivabradine (pure heart rate reducing agent)
● Midodrine (vasoconstrictor)
● Fludrocortisone (mineralocorticoid to increase volume)
● Droxidopa and pyridostigmine, used in selected cases
The selection of these agents must be tailored to the patient with regard to the form of PoTS and potential side effects. Most of these agents require specialist prescription and monitoring.
Why specialist input matters
PoTS is a complex, heterogeneous condition that mimics and overlaps with many other disorders. Misdiagnosis can lead to ineffective or harmful treatments. Most pharmacological therapies used in PoTS are off-label in the UK and require detailed knowledge of cardiovascular physiology, autonomic function and comorbidities.
At Hourglass Wellbeing, Aberdeen, we offer specialist, consultant-led evaluation and long-term management, coordinating care with physicians from multiple specialties, including cardiology, endocrinology as well as physiotherapists, exercise coaches and mental health professionals where needed.