Figure 2.

Electrode locations. We used OctoBioAmp (ADInstruments, Colorado Springs, CO) to record SKNA in healthy volunteers and in patients without heart disease or with electrical storm. We used the healthy volunteer protocol to test various electrocardiogram (ECG) lead positions. All subjects had unipolar recordings from the usual chest lead locations V1–V6, except for three whose lead V1 was moved to the right wrist and leads V2–V6 were shifted in the V1–V5 position for unipolar recording. All bipolar recordings were made with limb lead ECG patch electrodes placed on the arms, abdomen, or fingers. For patients undergoing a bilateral stellate ganglion injection procedure, a portable ME6000 device was used for data acquisition. (A) shows the portable (181 × 85 × 35 mm) ME6000 Biomonitor. One channel was used to record ECG Lead I (B). The red electrodes were placed in the subclavicular area and the black electrode served as reference. A second channel was used to record SKNA from the right arm (C) to avoid ECG contamination. RA=right arm electrode, LA=left arm electrode, RL=right leg electrode (reference), LL=left leg electrode, wrist=unipolar electrode (V1) placed at the wrist location, V1–V6=standard unipolar electrocardiogram leads. (From Online Data Supplement, Doytchinova et al, Heart Rhythm 2017)(47)