What are the diagnostic criteria for Postural Orthostatic Tachycardia Syndrome (POTS)?

From the Guidelines

Diagnosing Postural Orthostatic Tachycardia Syndrome (POTS) requires a comprehensive approach involving both clinical evaluation and specific testing, with the primary diagnostic criterion being an increase in heart rate of at least 30 beats per minute (or ≥40 bpm for those aged 12-19) within 10 minutes of standing, without a significant drop in blood pressure, as defined by the 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope 1.

Key Diagnostic Criteria

• Increase in heart rate of ≥30 bpm (or ≥40 bpm for those 12–19 years of age) within 10 minutes of standing
• Absence of orthostatic hypotension (>20 mm Hg reduction in systolic BP)
• Symptoms that occur with standing, such as lightheadedness, palpitations, tremulousness, generalized weakness, blurred vision, exercise intolerance, and fatigue

Diagnostic Approach

• Tilt table test or active stand test to monitor heart rate and blood pressure while changing from lying to standing position
• Thorough medical history and physical examination to identify symptoms that worsen when upright
• Additional tests, such as blood tests, ECG, and autonomic function tests, to rule out other conditions
• Symptom diary to note triggers and patterns, aiding in accurate diagnosis

Specialized Evaluation

• Evaluation by a cardiologist, neurologist, or dysautonomia specialist is recommended due to potential misdiagnosis resulting from overlapping symptoms with anxiety or deconditioning.

From the Research

Diagnostic Criteria for POTS

To diagnose Postural Orthostatic Tachycardia Syndrome (POTS), the following criteria are considered:

• A heart rate increment of 30 beats/min or more within 10 minutes of standing or head-up tilt in the absence of orthostatic hypotension 2
• The standing heart rate is often 120 beats/min or higher 2
• Symptoms of cerebral hypoperfusion and excessive sympathoexcitation 2

Evaluation of POTS

The evaluation of a patient with suspected POTS should:

• Establish the diagnosis 3
• Identify co-morbid conditions 3
• Exclude conditions that could cause or mimic the syndrome 3
• Utilize a careful clinical history and examination, laboratory, and autonomic testing 4
• Include a thorough history to identify mechanism of symptom onset, clinical features, associated clinical conditions or disorders, and factors that may result in symptom exacerbation 4
• Involve an assessment of pupillary responses, an evaluation for sudomotor and vasomotor signs, and an assessment for joint hypermobility 4

Autonomic Testing

Autonomic testing is used to:

• Confirm a POTS diagnosis 4
• Exclude other causes of orthostatic intolerance 4
• Characterize POTS into neuropathic and hyperadrenergic subtypes 4

Laboratory Testing

Laboratory testing helps to:

• Exclude mimics of autonomic dysfunction 4
• Recognize conditions that may exacerbate symptoms 4
• Identify conditions that may cause or be associated with autonomic nervous system disease 4

Other Diagnostic Studies

Other diagnostic studies, such as:

• Epidermal skin punch biopsy 4
• Exercise testing 4
• Radiographic studies 4
• Sleep studies 4
• Gastrointestinal motility studies 4
• Urodynamic studies 4 should be considered when clinically appropriate.

Note that the diagnosis of POTS can be complex and may require a comprehensive approach, as highlighted by the lack of a single universally accepted set of criteria 5.