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Updated: Aug 4, 2026
A Methodological Approach to Non-invasive Assessments of Vascular Function and Morphology
Published on: February 7, 2015
Noninvasive assessment of spontaneous baroreflex sensitivity and heart rate variability in patients with carotid
1Department of Neurology, Kaohsiung Medical University and Hospital, Kaohsiung, Taiwan.
Insights
Significant carotid stenosis is linked to reduced baroreflex sensitivity (BRS) and heart rate variability (HRV). These autonomic markers may predict cardiovascular outcomes in patients with carotid stenosis.
Area of Science:
- Cardiovascular Physiology
- Autonomic Nervous System Function
- Neurovascular Medicine
Background:
- Atherosclerosis may impair carotid sinus function and baroreflex sensitivity (BRS).
- Limited data exists on comparing BRS and heart rate variability (HRV) in carotid stenosis patients versus controls.
Purpose of the Study:
- To compare BRS and HRV in patients with carotid stenosis and healthy controls.
- To investigate the relationship between the degree of carotid stenosis and autonomic function markers.
Main Methods:
- 118 patients with transient ischemic attack/minor stroke and carotid stenosis (≥50%) were compared to 43 healthy controls.
- Carotid stenosis was diagnosed via ultrasound; patients were grouped by stenosis severity (50-75% vs. 75-99%).
- BRS and HRV were assessed noninvasively using finger plethysmography and fast Fourier transform analysis.
Main Results:
- 99 patients and 43 controls were analyzed; patients showed significantly decreased HRV (VLF, LF, HF components) compared to controls.
- Patients exhibited significantly reduced BRS across all measured indices (p < 0.001) compared to controls.
- No significant differences in BRS or HRV were found between patient groups with moderate versus high-grade stenosis.
Conclusions:
- Significant carotid stenosis is associated with reduced BRS and HRV.
- These autonomic markers may hold prognostic value for cardiovascular events in patients with carotid stenosis.
- Further prospective studies are warranted to confirm BRS and HRV as predictors of cardiovascular prognosis and lifespan.
Background:
Previous limited observations have suggested that atherosclerosis may affect the distensibility of the carotid sinus and then impair the baroreflex sensitivity (BRS). No studies have been done to compare the BRS and heart rate variability (HRV) in patients with carotid stenosis and normal controls.
Methods:
A convenience-consecutive sample of 118 patients with transient ischemic attack or minor stroke 3 months to 1 year before (mean 6 months) who met the study criteria were referred to the neurovascular laboratory of the study hospital. Forty-three age-matched healthy adults were recruited as the normal controls. The inclusion criteria for participation were (1) no diabetes mellitus, (2) no history, symptoms or ECG signs of coronary artery disease or myocardial infarction, and (3) presence of carotid stenosis greater than or equal to 50%. The diagnosis of carotid stenosis was made using color-coded duplex ultrasound with published criteria. We categorized the patients into two groups: group 1 had moderate stenosis (50-75%) and group 2 had high-grade stenosis (75-99%). Instantaneous systolic blood pressure (SBP) and heart rate of all participants were assessed noninvasively using servo-controlled infrared finger plethysmography. The fluctuation in SBP as well as the interpulse interval (IPI) was divided into three components at specific frequency ranges by fast Fourier transform as high frequency (HF; 0.15-0.4 Hz), low frequency (LF; 0.04-0.15 Hz) and very low frequency (VLF; 0.004-0.04 Hz). The BRS was expressed as (1) transfer function with its magnitude in the HF and LF ranges, (2) BRS index alpha, and (3) regression coefficient by sequence analysis. The HRV was expressed as total power and power in the three frequency ranges (HF, LF and VLF).
Results:
The final analysis included 99 patients (mean age 72 +/- 6 years, 79 male) and 43 healthy controls (mean age 68 +/- 7 years, 30 male). Forty-three patients were classified as group 1 (stenosis 50-75%) and 56 as group 2 (stenosis 75-99%). There was no significant difference in the IPI between patients and controls (p value = 0.8637). We observed a significant decrease in all three HRV components (VLF, LF and HF) in the patients; however, there were no differences between the two patient groups with various degrees of stenosis. All the indices of BRS, including the magnitude of SBP-IPI transfer function at LF and HF, the computed BRS index alpha and the regression coefficient of sequence analysis, revealed similar results. Patients exhibited a significant reduction in the BRS (p < 0.001) compared with controls, and no difference was found between the two groups of patients.
Conclusions:
Our study linked significant carotid stenosis to two important autonomic markers (BRS and HRV) that may have prognostic value for patients with cardiovascular events. Further prospective studies are needed to explore whether or not the decreased BRS and HRV can be predictors for poor cardiovascular prognosis, or even for shortened life span in general, in patients with significant carotid stenosis.
