Hemodialysis Efficiency Predictor in End-Stage Kidney Disease Using Real-Time Heart Rate Variability

Autonomic dysfunction as a long-term complication may occur in end-stage kidney disease (ESKD) patients and can be diagnosed using heart rate variability (HRV) analyzed from electrocardiogram (ECG) recordings. There is limited data about HRV using real-time ECG to predict hemodialysis (HD) efficiency in patients with ESKD who are routinely doing HD in the real world.

A total of 50 patients (62.1 ± 10.7 years) with ESKD underwent continuous real-time ECG monitoring (237.4 ± 15.3 min) during HD for HRV using remote monitoring system. Their electrolyte levels were checked before and after HD. We compared HRV according to electrolyte levels.

During the monitor, we checked the ECG and electrolyte levels simultaneously a total of 2374 times for all of the patients. Both time and frequency domain HRV were higher when the patients had lower K⁺ level (<0.5 mEq/L) and P⁺ level change (<2 mEq/L) before and after HD as compared to those with a higher K⁺ level (≥0.5 mEq/L) and P⁺ level change (≥2 mEq/L). Additionally, patients with lower K⁺ and P⁺ level change groups had higher incidences of arrhythmic events including atrial/ventricular premature complexes, despite no difference of mean heart rate (p < 0.001).

Higher HRV was independently associated with a poorly controlled K⁺ and P⁺ level during HD in patients with ESKD. This is consistently evidenced by the independent association between higher HRV, K⁺ and P⁺ levels in real time, suggesting that low electrolyte changes before and after HD alone may cause cardiac autonomic dysfunction.