From the Guidelines
Postural Orthostatic Tachycardia Syndrome (POTS) is characterized by a range of symptoms that occur when standing upright, including an abnormal increase in heart rate of at least 30 beats per minute within 10 minutes of standing, without a significant drop in blood pressure. The symptoms of POTS include:
- Lightheadedness
- Dizziness
- Brain fog
- Fatigue
- Heart palpitations
- Exercise intolerance
- Near-fainting (presyncope)
- Nausea
- Headaches
- Blurred vision
- Tremors
- Poor concentration
- Shortness of breath
- Chest pain
- Sweating abnormalities
- Purple discoloration in the legs when standing (blood pooling)
- Gastrointestinal issues such as bloating or constipation
- Sleep disturbances These symptoms occur because the autonomic nervous system fails to properly regulate blood vessel constriction when standing, causing blood to pool in the lower extremities and reducing blood flow to the brain and other organs 1. Symptoms typically worsen after prolonged standing, physical exertion, heat exposure, or during menstruation in females. The severity varies widely among patients, with some experiencing mild discomfort while others face significant disability affecting daily activities. It is essential to note that POTS is frequently associated with deconditioning, recent infections, chronic fatigue syndrome, joint hypermobility syndrome, and a spectrum of non-specific symptoms such as headache and chest pain 1. The pathophysiology of POTS is debated and likely heterogeneous, with proposed mechanisms including deconditioning, immune-mediated processes, excessive venous pooling, and a hyperadrenergic state 1.
From the Research
Symptoms of Postural Orthostatic Tachycardia Syndrome (POTS)
The symptoms of POTS can vary from person to person, but common symptoms include:
- Orthostatic intolerance, which is the inability to tolerate standing upright without experiencing symptoms such as dizziness, lightheadedness, and fainting 2
- A symptomatic increase in heart rate upon standing, which can be greater than 30 beats per minute within 10 minutes of standing 2
- Fatigue, exercise intolerance, and gastrointestinal distress 3
- Lightheadedness, tachycardia, and cognitive impairment 4
- Headaches, nausea, and abdominal pain 5
Subtypes of POTS and Their Associated Symptoms
There are three primary subtypes of POTS, each with distinct symptoms:
- Hyperadrenergic POTS: characterized by excessive norepinephrine production or impaired reuptake, leading to sympathetic overactivity 6
- Neuropathic POTS: resulting from impaired vasoconstriction during orthostatic stress, leading to symptoms such as lightheadedness and fainting 6
- Hypovolemic POTS: often triggered by dehydration and physical deconditioning, leading to symptoms such as fatigue and exercise intolerance 6
Triggering Factors
POTS symptoms can be triggered by various factors, including: