Dynamics of Cardiac Autonomic Responses During Hemodialysis Measured by Heart Rate Variability and Skin Sympathetic Nerve Activity: The Impact of Interdialytic Weight Gain

Abstract

Background: Autonomic nervous regulation plays a critical role in end-stage kidney disease (ESKD) patients with cardiovascular complications. However, studies on autonomic regulation in ESKD patients are limited to heart rate variability (HRV) analysis. Skin sympathetic nerve activity (SKNA), which noninvasively reflects the sympathetic nerve activity, has not been used in ESKD patients.Methods: Seventy-six patients on maintenance hemodialysis (MHD) treatment (a 4-h HD session, three times a week) were enrolled. Utilizing a noninvasive, single-lead, high-frequency recording system, we analyzed the dynamic change in HRV parameters and SKNA during HD. The different characteristics between the subgroups divided based on interdialytic weight gain (IDWG, <3 kg or ≥3 kg) were also demonstrated.Results: After the HD, values for heart rate (75.1 ± 11.3 to 80.3 ± 12.3 bpm, p < 0.001) and LF/HF (1.92 ± 1.67 to 2.18 ± 2.17, p = 0.013) were significantly higher than baseline. In subgroup analysis, average voltage of skin sympathetic nerve activity (aSKNA) in IDWG ≥3 kg group was lower than the IDWG <3 kg group at the end of MHD (1.06 ± 0.30 vs 1.32 ± 0.61 μV, p = 0.046). Moreover, there was a linear correlation between mean heart rate (HR) and aSKNA in low IDWG patients (p < 0.001), which was not found in high IDWG patients. At the 1-year follow-up, high IDWG patients had a higher incidence of cardiovascular hospitalization (p = 0.046).Conclusions: In MHD patients, a gradual activation of sympathetic nerve activity could be measured by HRV and aSKNA. A lower aSKNA at the end of HD and a loss of HR-aSKNA correlation in overhydrated patients were observed. Extensive volume control is promising to improve the autonomic nervous function and clinical outcomes in this population.

Hemodialysis Effects on Autonomic Function: Results of Linear and Nonlinear Analysis of Heart Rate Variability at Rest and in Response to Physical and Mental Stress Tests

“…In 35 patients, Tong et al showed that SD of beatto-beat intervals (SDNN) and LF/HF ratio decreased significantly 3 h after the start and almost recovered 2 h after the end of the hemodialysis session [33]. In another study in 76 patients, SDNN fluctuated, LF/HF power significantly increased, while entropy decreased during hemodialysis, suggesting a possible shift toward sympathetic hyperactivity [34]. In contrast, Rubinger et al reported that LF/HF power decreased during dialysis and was significantly lower in hemodynamically unstable patients [17].…”

Alterations of sympathetic dynamics after atrial fibrillation ablation by analysis sympathetic nerve activity provide prognostic value for recurrence and mechanistic insights into ablation

“…In addition to predicting AF recurrence, there are new applications in neuECG, such as acting as markers of orthostatic hypotension and recurrent syncope ( 30 , 31 ), predicting the occurrence of ventricular arrhythmia in acute coronary syndrome ( 32 ), and correlating with intradialytic weight gain in patients with end-stage renal disease ( 33 ). It has also been proposed as a marker of fitness ( 34 ) and to predict neurological recovery of patients who had cardiac arrest and are undergoing therapeutic hypothermia ( 35 ).…”

Autonomic nervous activity analysis based on visibility graph complex networks and skin sympathetic nerve activity

“…However, the acquisition of these employed features was complicated, and it still required more other biomarkers or calculated features to improve the quantification accuracy for practical clinical applications. The SKNA had been applied to evaluate the ANS as a non-invasive method in many clinical applications (Zhang et al, 2022), and many SKNA-derived metrices (e.g., aSKNA, bSKNA) had been validated and used for ANS qualification. Nevertheless, these parameters were susceptible to noise.…”

“…Although these parameters can reflect the ANS changes by empirical threshold-based nerve bursts detection, the low signal-to-noise ratio of SKNA will lead to misjudgments (Xing et al, 2022a). In addition, the low amplitude SKNA signal (0.5-80 µV) is susceptible to noise, increasing the difficulty of extracting sympathetic-related information (Zhang et al, 2022). Therefore, more work is still needed to effectively analyze the autonomic nervous activity from SKNA, especially in real-time application.…”