Table 2.
A summary of clinical studies with respect to the association between heart rate variability and non-invasive endothelial function testing
| Year | Authors | Subjects | Main findings |
|---|---|---|---|
| HRV and FMD | |||
| 2007 | Kaufman CL, et al. [39] | 36 children (19 M, 17F, 11.5 ± 0.1 years) | FMD peak dilation was positively related to HFnu and negatively related to LF/HF ratio. The correlation is independent of fat mass, inflammation, and fasting insulin level |
| 2012 | Pinter A, et al. [40] | 46 healthy young males, (22 ± 6) years | RMSSD, pNN50, and lnHF power have positive correlations with normalized FMD |
| 2013 | Truccolo AB, et al. [41] | 13 patients with Chagas disease in its indeterminate phase, (59 ± 11) years | A positive correlation with FMD was observed in both normalized HF and LF spectral components, while LF/HF ratio was negatively correlated with FMD |
| 2013 | Watanabe S, et al. [42] | 47 patients with ischemic heart disease, (68 ± 7) years | FMD was correlated with SDNN and LF/HF. LF/HF was identified as the most powerful predictor of the magnitude of FMD |
| HRV and EndoPAT | |||
| 2021 | Tuttolomondo A, et al. [43] | 63 patients with diabetic foot (67 ± 10 years), 30 patients with diabetes and without ulcerative complications (61 ± 9 years), and 30 controls without diabetes (65 ± 6 years) | RHI measured by the Endo-PAT has a positive correlation with LF/HF ratio in subjects with type 2 diabetes mellitus with diabetic foot. RHI was negatively correlated with RMSDD and HF% in patients with diabetic foot |
| HRV and IMT | |||
| 2006 | Eller NH, et al. [44] | 84 healthy individuals (25 men, 43–63 years) | SDNN and LF/HF difference (stress test vs. sleep) were found to be negatively correlated to IMT progression four years after baseline |
| 2006 | Gottsäter A, et al. [45] | 61 type 2 diabetes patients (39 males, 45–69 years) | Mean IMT in the common carotid artery correlated with LF power |
| 2012 | Fakhrzadeh H, et al. [46] | 57 diabetic (51 ± 5 years) and 54 nondiabetics (49 ± 6 years) subjects free of coronary artery disease | Increased carotid IMT was inversely and independently associated with the total power of HRV in both groups |
| 2013 | Galetta F, et al. [47] | 32 elderly sedentary subjects (65 ± 4 years) and 32 age-matched endurance athletes (66 ± 4 years) | In both groups, SDNN was inversely related to IMT, while LF/HF ratio related positively to IMT |
| 2017 | Pereira VL Jr, et al. [48] | 101 subjects (60 ± 13 years) with an estimated 10-year atherosclerosis cardiovascular disease risk score of 16.4 ± 17.0 | A statistically significant association between SDNN and carotid IMT was found. IMT was also associated with coefficient of variation of RR intervals and dispersion of points along the line of identity (SD2) |
| 2020 | Hoshi RA, et al. [49] | 7256 apparently healthy adults (mean age 50 years) | An increased odds ratio for carotid IMT ≥ 75th percentile was verified within the lowest two quartiles of LF and HF, but significances did not remain after adjustments for anthropometric and clinical variables |
| HRV and EAT | |||
| 2014 | Balcioğlu AS, et al. [50] | 224 patients (56 ± 17 years) with premature ventricular beats complaining of palpitations | Significant correlations were found between EAT thickness and Holter findings, including SDNN, SDNN index, SDANN, RMSSD, and pNN50 |
| HRV and pulse wave velocity | |||
| 2004 | Nakao M, et al. [51] | 382 Japanese males (24–39 years) | PWV was positively associated with LF/HF ratio. LF/HF was an independent predictor of PWV after controlling for significant effects of age, systolic blood pressure, and plasma noradrenaline levels |
| 2014 | Chandra P, et al. [52] | 240 patients (mean age 60 years) with chronic kidney disease stage III–V | Several HRV measures (LF, VLF, LF/HF ratio, total power, and SDANN) were inversely correlated with PWV. However, the association was attenuated after adjustment for age and diabetes and no longer significant after adjustment for C-reactive protein |
| 2019 | Shah AS, et al. [53] | 397 patients (21 ± 3 years) enrolled in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study | Participants with ≥ 3 abnormal HRV indices that were greater or less than 2.5 standard deviations compared with control adolescents had greater pulse wave velocity compared with those without dysfunction |
EAT epicardial adipose tissue, FMD flow-mediated dilation, HF high frequency, HRV heart rate variability, IMT intima media thickness, LF low frequency, pNN50 percentage of successive RR intervals that differ by more than 50 ms, PWV pulse wave velocity, RHI reactive hyperactivity index, RMSSD root mean square of successive RR interval differences, SDANN standard deviation of the average NN intervals for each 5-min segment of a 24-h HRV recording, SDNN standard deviation of NN intervals, VLF very low frequency