Single limb electrocardiogram using vector mapping: Evaluation and validation of a novel medical device

The Tiger Tech Warfighter Monitor (WFM) is a novel single-limb device for ECG acquisition. The WFM provides true (not derived) single limb Electrocardiogram monitoring (ECG) to provide heart rate and R-R interval monitoring between QRS complexes. Herein, we evaluate the diagnostic accuracy of the WFM heart rate, R-R interval monitoring, and heart rate variability monitoring in comparison to a 2‑lead chest ECG.

Data was collected under Institutional Review Board (IRB) approval. Patients available within our institution's pre-operative holding unit were randomly selected to undergo simultaneous chest and WFM ECG monitoring. 3-5-min measurements were taken depending on the patient's availability. Data was saved to two separate mobile phones and time-stamped for synchronization. A proprietary Tiger Tech extraction algorithm was used to tag proper features on both the WFM 1-Limb ECG and Chest ECG data files. A separate algorithm was then used to compare the beat-to-beat variations between the ECGs.

Data was extracted and analyzed on 26 subjects. Linear regression of heart rate analysis revealed excellent correlations with an R² of 0.99 (p < 0.05). Similar linear regression evaluation of R-R interval correlation demonstrated a mean R² value of 0.95 (p < 0.05). Statistically significant correlation was achieved in all 26 included study participants. Heart rate variability also achieved excellent correlation (SDNN R² = 0.997, RMSSD R² = 0.995, LnRMSSD R² = 0.992, p << 0.05).

Results demonstrate that the WFM achieves excellent correlation with chest ECG for heart rate, R-R internals, and heart rate variability.