The role of carotid plaque echogenicity in baroreflex sensitivity

The Impact of Unilateral and Bilateral Eversion Carotid Endarterectomy on Postoperative Hemodynamic Parameters

Background:

Carotid endarterectomy (CEA) is an effective and safe treatment of stenosed carotid arteries, and is a preventive operation with well-defined indications. It is associated with a loss of the baroreceptor reflex and postoperatively increased hemodynamic parameters.

Objective:

The aim of the study was to confirm the sensitivity of baroreceptors and the impact on arterial pressure and heart rate in unilateral and bilateral eversion carotid endarterectomies.

Methods:

A retrospective study was conducted with 30 patients treated with E-CEA in local anesthesia at the Clinic for cardiovascular surgery from December 2019 to May 2021, due to stenosis of the carotid arteries. Patients were divided into two groups: 15 patients in group A (patients with unilateral E-CEA; 15 patients in group B: patients with bilateral E-CEA).

Results:

Out of the total of 30 patients included in the research, 15 patients in groups A and B respectively, there were no statistically significant differences in regards to gender (p= 0,245) and preoperative risk factors: smoking (p=0,449); hypertension (p=0,388); diabetes (p= 0,714); hyperlipidemia (p=0.388), coronary disease (p=0.461) and symptomatic stenosis of the carotid arteries (p=0.449). Noted were the statistically significant differences in values of systolic and diastolic pressure on the 3rd postoperative days in patients with bilateral E-CEA (p=0,001; p=0,001), a statistically significant difference in the heart rate was not found in the analyzed groups in the postoperative period (p=0,225; p=0,994).

Conclusion:

This study identified statistically significant differences in values of systolic and diastolic pressure in the early postoperative period. In his period, early detection and correction of these hemodynamic disorders are needed.

The roles of FGF21 in atherosclerosis pathogenesis

FGF21 is a peptide hormone that regulates homeostasis of lipid and glucose as well as energy metabolism. It is mainly expressed and secreted in liver and adipose tissues, and it is expressed in lower amounts in the aorta. Recent clinical and preclinical studies indicate increased serum FGF21 levels in atherosclerosis patients. Also, FGF21 therapy has been reported to reduce the initiation and progression of atherosclerosis in animal models and in vitro studies. Moreover, growing evidence indicates that administration of exogenous FGF21 induces anti-atherosclerotic effects, because of its ability to reduce lipid profile, alleviation of oxidative stress, inflammation, and apoptosis. Therefore, FGF21 can not only be considered as a biomarker for predicting atherosclerosis, but also induce protective effects against atherosclerosis. Besides, serum levels of FGF21 increase in various diseases including in diabetes mellitus, hypertension, and obesity, which may be related to initiating and exacerbating atherosclerosis. On the other hand, FGF21 therapy significantly improves lipid profiles, and reduces vascular inflammation and oxidative stress in atherosclerosis related diseases. Therefore, further prospective studies are needed to clarify whether FGF21 can be used as a prognostic biomarker to identify individuals at future risk of atherosclerosis in these atherosclerosis-associated diseases. In this review, we will discuss the possible mechanism by which FGF21 protects against atherosclerosis.

Association between Carotid Intima Media Thickness and Heart Rate Variability in Adults at Increased Cardiovascular Risk

Background: Atherosclerotic carotid intima-media thickness (IMT) may be associated with alterations in the sensitivity of carotid baroreceptors. The aim of this study was to investigate the association between carotid IMT and the autonomic modulation of heart rate variability (HRV). Methods: A total of 101 subjects were enrolled in this prospective observational study. The carotid IMT was determined by duplex ultrasonography. The cardiac autonomic function was determined through HRV measures during the Deep Breathing Test. Linear regression models, adjusted for demographics, comorbidities, body mass index, waist-hip-ratio, and left ventricular ejection fraction were used to evaluate the association between HRV parameters and carotid IMT. Results: Participants had a mean age of 60.4 ± 13.4 years and an estimated 10-year atherosclerotic cardiovascular disease (ASCVD) risk score (using the Pooled Cohort Equations) of 16.4 ± 17. The mean carotid media thickness was highest (0.90 ± 0.19 mm) in the first quartile of the standard deviation of all RR intervals (SDNN) (19.7 ± 5.1 ms) and progressively declined in each subsequent quartile to 0.82 ± 0.21 mm, 0.81 ± 0.16 mm, and 0.68 ± 0.19 in quartiles 2 (36.5 ± 5.9 ms), 3 (57.7 ± 6.2 ms) and 4 (100.9 ± 22.2 ms), respectively. In multivariable adjusted models, there was a statistical significant association between SDNN and carotid IMT (OR -0.002; 95%CI -0.003 to -0.001, p = 0.005). The same significant association was found between carotid IMT and other measures of HRV, including coefficient of variation of RR intervals (CV) and dispersion of points along the line of identity (SD2). Conclusions: In a cohort of individuals at increased cardiovascular risk, carotid IMT as a marker of subclinical atherosclerosis was associated with alterations of HRV indicating an impaired cardiac autonomic control, independently of other cardiovascular risk factors.

Assessing spontaneous baroreflex in aged with pulse-pulse intervals and pulse amplitudes

Cardiac autonomic dysfunction is a serious condition in the elder subjects. Baroreflex sensitivity (BRS) by measuring pulse intervals and blood pressure has been proven as an effective indicator. This paper proposes a novel index by substitution blood pressure with amplitudes of pressure pulse. We recruited 61 subjects divided into two groups: healthy young subjects (Group1, n=33), healthy elders (Group2, n=28). The wrist pulse pressures of each subject were measured for 5 minutes to obtain pulse-pulse intervals and amplitudes then applied within the spontaneous sequence technique to calculate the pulse-pulse interval and amplitude ratio (PAR). We verified the reproducibility of PAR and agreement with spectral analysis of heart rate variability in group1 participants. We discovered significant differences between different groups in PAR (Group1 vs. Group2: 0.90 ± 0.42 vs. 0.62 ± 0.27, P=0.010). In contrast with measurements of BRS, this study proposes a simple approach without the necessity of blood pressure calibration or professional expertise to conduct measurements, thereby providing a convenient method for assessing autonomic function at home.