POTS (Postural Orthostatic Tachycardia Syndrome)
What is It?
Postural Orthostatic Tachycardia Syndrome (POTS) is a disorder of the autonomic nervous system characterised by an abnormal and excessive increase in heart rate upon standing. By definition, POTS involves a heart rate rise of 30 beats per minute or more (or above 120 bpm) within 10 minutes of standing, in the absence of significant low blood pressure. POTS is more common in women, particularly those aged 15-50, and may develop following viral infections, pregnancy, surgery, or trauma. It is increasingly recognised as a cause of significant disability and reduced quality of life.
What are the symptoms?
Symptoms of POTS typically worsen on standing and improve on lying down. Common symptoms include a rapid heartbeat (palpitations) upon standing, dizziness or lightheadedness, near-fainting or fainting (syncope), brain fog or difficulty concentrating, fatigue, headaches, tremulousness, blurred vision, and shortness of breath. Some patients also experience nausea, chest pain, and exercise intolerance. Symptoms can vary significantly between individuals and may fluctuate day to day.
What are the causes?
At One Heart Centre our cardiologists screen for all causes of POTS. POTS is often multifactorial and the exact mechanism may differ between patients. Contributing factors include:
- Post-viral or post-infectious triggers: Including COVID-19, Epstein-Barr virus and other viral illnesses.
- Autoimmune mechanisms: Autoantibodies affecting autonomic nerve function have been identified in some patients.
- Deconditioning and reduced blood volume: Contributing to the inability to adequately regulate blood pressure on standing.
- Connective tissue disorders: Such as hypermobile Ehlers-Danlos syndrome (hEDS), which affects blood vessel and tissue support.
- Other associations: Mast cell activation syndrome (MCAS), small fibre neuropathy, and hormonal fluctuations.
How is it investigated?
Diagnosis of POTS requires a careful history and an active stand test or tilt table test, measuring heart rate and blood pressure changes on standing. Your One Heart Centre cardiologist will perform a 12-lead ECG and echocardiogram to exclude structural heart disease. Ambulatory ECG and blood pressure monitoring may be arranged to characterise the condition further. Blood tests are performed to identify underlying causes such as anaemia, thyroid disease, or electrolyte imbalances. In selected cases, additional autonomic function testing or specialist referral may be required.
What are the treatments?
At One Heart Centre our cardiologists have post-fellowship training in managing POTS and will provide a personalised treatment plan for your condition. Management typically involves a combination of non-pharmacological and pharmacological strategies. Treatment options include:
- Lifestyle measures: Increasing fluid and salt intake, wearing compression garments, elevating the head of the bed, and avoiding prolonged standing or heat exposure.
- Graduated exercise therapy: A structured, supervised exercise programme to improve cardiovascular deconditioning is a cornerstone of long-term management.
- Medical therapy: Medications such as beta-blockers (to reduce heart rate), fludrocortisone (to expand blood volume), midodrine (to increase blood pressure), or ivabradine (to control heart rate) may be used depending on the patient’s profile.
- Treating underlying conditions: Addressing contributing factors such as autoimmune disease, anaemia, thyroid dysfunction, or mast cell activation.
- Multidisciplinary care: Coordination with physiotherapy, psychology, and other specialists to support comprehensive management of this complex condition.