Physiological and clinical comparison of active stand and head-up tilt tests in Postural Orthostatic Tachycardia Syndrome (POTS).

This study compares the hemodynamic responses and diagnostic accuracy of the Active Stand Test (AST) and Head-Up Tilt Test (HUT) in diagnosing Postural Orthostatic Tachycardia Syndrome (POTS). Sixty POTS patients underwent both tests in a single day, with beat-to-beat hemodynamics recorded. The research aimed at evaluating the changes in heart rate from baseline during the two testing methods. Findings showed a significant increase in heart rate over the duration of both tests, although the abstract truncates before specifying comparative diagnostic accuracy outcomes. These insights are important for understanding which test may better diagnose POTS under standardized conditions.