Postural orthostatic tachycardia syndrome
Postural orthostatic tachycardia syndrome is an excessive heart-rate rise on standing (at least 30 beats per minute) with orthostatic symptoms but without orthostatic hypotension. It predominantly affects young women, is diagnosed after excluding other causes, and is managed with volume expansion, exercise reconditioning, and rate-modulating drugs.
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What this article covers
- Overview
Definition: postural orthostatic tachycardia syndrome (POTS) is a sustained heart-rate increase of at least 30 beats per minute (40 in adolescents) within 10 minutes of standing, with orthostatic symptoms and without orthostatic hypotension.
- Epidemiology
Predominantly affects young women. Often follows a viral illness or period of deconditioning.
- Risk factors
Female sex and young adulthood. Recent viral illness, prolonged bed rest, or deconditioning.
- Pathophysiology
Excessive orthostatic tachycardia: on standing, an exaggerated heart-rate rise compensates for impaired venous return.
- Clinical features
Palpitations, lightheadedness, and presyncope on standing.
- Differential diagnosis
Orthostatic hypotension: a blood-pressure fall rather than isolated tachycardia (Orthostatic hypotension).
- Diagnosis
Establish by an excessive orthostatic heart-rate rise with symptoms and no orthostatic hypotension, after excluding other causes: the diagnostic basis is a sustained heart-rate increase of at least…
- Management
First-line, volume expansion and exercise reconditioning: increase fluid (2 to 3 liters/day) and salt intake, use compression garments, and begin a structured, progressive (initially recumbent)…
- Complications
Disability and reduced quality of life. Falls from presyncope.
- Prognosis
Non-life-threatening, and many improve over time, especially with reconditioning.
- Prevention
Maintain hydration, salt, and aerobic conditioning: fluid intake of 2 to 3 liters per day and salt intake of 8 to 10 g per day.
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Related articles
- Orthostatic hypotension
Orthostatic hypotension is a sustained fall in blood pressure on standing (at least 20 mmHg systolic or 10 mmHg diastolic), causing lightheadedness, presyncope, and falls. Causes include volume depletion, drugs, and autonomic failure; management is removing offenders, nonpharmacologic measures, and, when needed, fludrocortisone or midodrine.
- Syncope
Syncope is a transient loss of consciousness from global cerebral hypoperfusion with spontaneous complete recovery. The central task is separating benign reflex and orthostatic causes from dangerous cardiac syncope, using history, examination, and ECG, since cardiac syncope carries a risk of sudden death; treatment is directed by mechanism, from reassurance and hydration for reflex syncope to a pacemaker, ICD, or structural intervention for cardiac syncope.
- Inappropriate sinus tachycardia
Inappropriate sinus tachycardia is a persistently elevated resting sinus rate, or an exaggerated rate response to minimal exertion, without an identifiable secondary cause. It is a diagnosis of exclusion in young women, and treatment centers on beta-blockade or ivabradine after ruling out reversible drivers.
- Supraventricular tachycardia
Supraventricular tachycardia is any tachyarrhythmia arising at or above the AV node, usually a regular narrow-complex tachycardia. Acute management of a stable regular narrow-complex SVT is vagal maneuvers then adenosine; unstable patients receive synchronized cardioversion, and definitive therapy is catheter ablation.