Table 3: Investigation of Postural Tachycardia Syndrome According to the Heart Rhythm Society.

Recommendation	CoR	LoE
A complete history and physical exam with orthostatic vital signs and 12-lead ECG should be performed in patients being investigated for POTS.	I	E
Complete blood count and thyroid function studies can be useful in selected patients being assessed for POTS.	IIa	E
A 24-hour Holter monitor might be considered in selected patients being assessed for POTS, although clinical efficiency is uncertain.	IIb	E
Detailed autonomic testing, transthoracic echocardiogram, tilt table testing, or exercise stress testing might be considered in selected patients being assessed for POTS.	IIb	E

CoR = class of recommendation; LoE = level of evidence; POTS = postural orthostatic tachycardia syndrome.[1]