Which initial investigations are recommended for a patient presenting with symptoms suggestive of POTS?

For a patient presenting with symptoms suggestive of postural orthostatic tachycardia syndrome (POTS), the initial investigations should focus on assessing orthostatic intolerance and excluding other causes of syncope or tachycardia. This includes:

• Detailed clinical history and symptom assessment to characterize orthostatic intolerance symptoms such as light-headedness, palpitations, and near-fainting on standing, and to distinguish POTS from other causes like postural hypotension ².
• Measurement of lying and standing blood pressure and heart rate to document the characteristic significant rise in pulse rate on standing without a significant drop in blood pressure, which defines POTS ².
• 12-lead ECG to exclude cardiac arrhythmias or conduction abnormalities that might mimic or coexist with POTS ¹.
• Consideration of further cardiovascular assessment if initial findings suggest structural heart disease or arrhythmia, including ambulatory ECG monitoring as appropriate ¹.

Routine tilt table testing is not recommended as a first-line investigation for suspected cardiac arrhythmic causes and is generally reserved for specific syncope diagnoses rather than POTS ¹.