Noninvasive potassium determination using a mathematically processed ECG: Proof of concept for a novel "blood-less, blood test"

作者：Dillon John J; DeSimone Christopher V; Sapir Yehu; Somers Virend K; Dugan Jennifer L; Bruce Charles J; Ackerman Michael J; Asirvatham Samuel J; Striemer Bryan L; Bukartyk Jan; Scott Christopher G; Bennet Kevin E; Mikell Susan B; Ladewig Dorothy J; Gilles Emily J; Geva Amir; Sadot Dan; Friedman Paul A^*

来源：Journal of Electrocardiology, 2015, 48(1): 12-18.

DOI：10.1016/j.jelectrocard.2014.10.002

• Potassium
• ECG
• Signal processing
• T-wave
• Dialysis
• Hyperkalemia

Objective: To determine if ECG repolarization measures can be used to detect small changes in serum potassium levels in hemodialysis patients.
Patients and Methods: Signal-averaged ECGs were obtained from standard ECG leads in 12 patients before, during, and after dialysis. Based on physiological considerations, five repolarization-related ECG measures were chosen and automatically extracted for analysis: the slope of the T wave downstroke (T right slope), the amplitude of the T wave (T amplitude), the center of gravity (COG) of the T wave (T COG), the ratio of the amplitude of the T wave to amplitude of the R wave (T/R amplitude), and the center of gravity of the last 25% of the area under the T wave curve (T4 COG) (Fig. 1).
Results: The correlations with potassium were statistically significant for T right slope (P < 0.0001), T COG (P = 0.007), T amplitude (P = 0.0006) and T/R amplitude (P = 0.03), but not T4 COG (P = 0.13). Potassium changes as small as 0.2 mmol/L were detectable.
Conclusion: Small changes in blood potassium concentrations, within the normal range, resulted in quantifiable changes in the processed, signal-averaged ECG. This indicates that non-invasive, ECG-based potassium measurement is feasible and suggests that continuous or remote monitoring systems could be developed to detect early potassium deviations among high-risk patients, such as those with cardiovascular and renal diseases. The results of this feasibility study will need to be further confirmed in a larger cohort of patients.

• 出版日期2015-2