Cardiac Autonomic Neuropathy in Patients with Chronic Renal Failure on Hemodialysis

Abstract

To characterize uremic cardiac autonomic neuropathy, we measured plasma catecholamines, analyzed the 24-hour heart rate variability (HRV), and acquired serial images with ¹²³I-metaiodobenzylguanidine (MIBG) in 44 patients with chronic renal failure on hemodialysis and in 14 controls. Time-domain measures were calculated using the Marquette HRV program. MIBG clearance rates from the heart and lung were evaluated on planar images, and the regional MIBG uptake in the left ventricular myocardium was evaluated with single-photon emission computed tomography. Compared with controls, plasma dopamine and norepinephrine levels were elevated (p < 0.001 and p = 0.03, respectively), and all the time-domain measures of HRV were reduced in the patients (p < 0.001). The MIBG clearance rate from the heart was higher (p < 0.001), that from the lung was lower (p < 0.001), and the myocardial MIBG distribution was more heterogeneous in patients than in controls (total uptake score p ≤ 0.03). These variables were similar between 26 patients without and 18 patients with hypertension. Uremic cardiac autonomic neuropathy may be characterized by high plasma levels of dopamine and norepinephrine, reduced HRV, and abnormal MIBG kinetics in the heart with heterogeneous myocardial MIBG distribution, suggesting cardiac sympathetic overactivity and parasympathetic deterioration. In addition, abnormal MIBG kinetics in the lung may imply pulmonary sympathetic nervous dysfunction and/or endothelial dysfunction in uremic patients.

Parathyroidectomy and Heart Rate Variability in Patients with Stage 5 CKD

“…It seemed to be caused by impairment of the cardiovascular autonomic control characterized by withdrawal in parasympathetic modulation and predominance in sympathetic tone (28). As in previous studies (17)(18)(19)(20)(29)(30)(31)(32)(33), our results showed that stage 5 CKD patients exhibited a marked reduction in HRV indices relative to age-and sex-matched controls, indicating that sympathetic hyperactivity may play an important role in increasing the risk of CVD among ESRD patients.…”

The Subjective Sleep Quality and Heart Rate Variability in Hemodialysis Patients

“…34 A reduction of HRV in ESRD patients has been demonstrated in some earlier reports, [19][20][21]35 whereas some other groups reported increased LF power. 36 This discrepancy may be related to clinical or methodological differences.…”

Nonlinear Measures of Heart Rate Variability and Mortality Risk in Hemodialysis Patients

“…Earlier studies have reported that sympathetic nerve activity is increased in hemodialysis patients (15,26) and an elevated plasma NE level independently predicts mortality (27). Scaling exponent a 1 decreases with increased levels of circulating noradrenaline in healthy men (28) and increases with b-blocker therapy in Data are n (%) for categorical data, median (interquartile range) for continuous normally distributed data, and mean 6 SD for those not normally distributed.…”

“…Interestingly, it also increases with atropine and decreases with vagal activation (28,31). Because vagal activity is generally reduced in hemodialysis patients (15)(16)(17), those with and without sympathetic overactivity might be better discriminated by scaling exponent a 1 than by the measures simply reflecting vagal modulation. This study has several limitations.…”

“…Several studies have indicated that these nonlinear HRV measures have greater predictive power than conventional HRV measures for mortality after myocardial infarction (MI) (12)(13)(14). In hemodialysis patients, the nonlinear measures might have greater discrimination ability than conventional measures, because cardiac vagal dysfunction is almost commonly observed among these patients (15)(16)(17). Although alterations in nonlinear HRV measures have been reported in hemodialysis patients (18,19), their prognostic value has not been examined with a sufficient sample size.…”