Signs and Symptoms of Postural Orthostatic Tachycardia Syndrome (POTS)
POTS presents with severe orthostatic intolerance symptoms triggered by standing, most commonly affecting young women, characterized by marked tachycardia (heart rate increase >30 bpm or >120 bpm absolute within 10 minutes of standing) without orthostatic hypotension. 1
Cardinal Diagnostic Features
Cardiovascular manifestations:
- Palpitations - reflecting the excessive sinus tachycardia that defines the condition 1
- Heart rate increase ≥30 bpm within 10 minutes of standing (or ≥40 bpm in patients aged 12-19 years) 1
- Standing heart rate frequently exceeds 120 bpm 2
- Absence of orthostatic hypotension (no sustained systolic BP drop ≥20 mmHg or diastolic BP drop ≥10 mmHg) 1
Primary Orthostatic Symptoms
Cerebral hypoperfusion symptoms that develop upon standing:
- Light-headedness and dizziness - among the most prominent complaints 1
- Generalized weakness and fatigue - often debilitating 1
- Blurred vision - from reduced cerebral perfusion 1
- Tremor - reflecting sympathetic overactivity 1
- Presyncope or frank syncope may occur 3, 4
Visual disturbances include:
- Blurring, enhanced brightness, loss of color perception, tunnel vision, and potentially complete loss of vision 1
Auditory symptoms:
- Impaired hearing, crackles, tinnitus, or sounds perceived as distant 1
Autonomic Activation Signs
Sympathetic overactivity manifestations:
Non-Specific Associated Symptoms
POTS frequently presents with a spectrum of additional complaints:
- Headache - commonly reported 1, 2
- Exercise intolerance - often severe and limiting 1, 3
- Shortness of breath 3
- Cognitive complaints including memory impairment, attention deficit, and "brain fog" 1
- Sleep disturbances or nonrestorative sleep 1
- Postexertional malaise 1
- Abdominal discomfort 4
Temporal Pattern and Exacerbating Factors
Critical diagnostic clues:
- Symptoms develop upon standing and are relieved by sitting or lying down 1
- Worse in the morning 1
- Exacerbated by heat exposure 1
- Worsened after meals 1
- Aggravated by exertion 1
Associated Conditions
POTS frequently coexists with:
- Deconditioning - often following a period of illness or injury 1, 4
- Recent infections - viral illness commonly precedes onset 1
- Chronic fatigue syndrome 1
- Joint hypermobility syndrome or hypermobile Ehlers-Danlos syndrome 1, 5
- Functional gastrointestinal disorders 2
- Functional bladder disorders 2
- Fibromyalgia 2
Demographics
Typical patient profile:
- Predominantly affects young women 1
- Most common adolescent presentation occurs in teenagers within 1-3 years of their growth spurt 4
- Symptoms must persist for at least 3 months for formal diagnosis 1
Clinical Pitfalls
The diagnosis requires distinguishing POTS from other causes of tachycardia including inappropriate sinus tachycardia, anxiety disorders, dehydration, anemia, hyperthyroidism, and pheochromocytoma 1, 2. The presence of orthostatic hypotension excludes the diagnosis of POTS and suggests alternative conditions such as classical orthostatic hypotension or vasovagal syncope 1.