When billing for ANS Testing, here a few key things to keep in mind in terms of which code to use:

Code 95924: should be reported only when both the parasympathetic function and the adrenergic function are tested together with the use of a tilt table. To report autonomic function testing that does not include beat‐to‐beat recording, or for testing
without use of a tilt table, use 95943.

CPT 95921: Testing of autonomic nervous system function; cardiovagal innervation (parasympathetic function), including two or more of the following: heart rate response to deep breathing with recorded R‐R interval, Valsalva ratio, and 30:15 ratio

CPT 95922: Vasomotor adrenergic innervation (sympathetic adrenergic function), including beat‐to‐beat blood pressure and R‐R interval changes during Valsalva maneuver and at least 5 minutes of passive tilt Do not report 95922 in conjunction with 95921

CPT 95924: combined parasympathetic and sympathetic adrenergic function testing with at least 5 minutes of passive tilt Do not report 95924 in conjunction with 95921 or 95922

CPT 95943: Simultaneous, independent, quantitative measures of both parasympathetic function and sympathetic function, based on time‐frequency analysis of heart rate variability concurrent with time‐frequency analysis of continuous respiratory activity, with mean heart rate and blood pressure measures, during rest, paced (deep) breathing, Valsalva maneuvers, and head‐up postural change Do not report 95943 in conjunction with 93040, 95921, 95922, 95924

CPT 95923: sudomotor, including one or more of the following: quantitative sudomotor axon reflex test (QSART), silastic sweat imprint, thermoregulatory sweat test, and changes in sympathetic skin response