Relationship between the coronary artery calcium quantification and gut microbiota composition in subjects without previous cardiovascular disease: A pilot study

AIM

To investigate the relationship between gut microbiota composition and the presence of coronary atherosclerosis assessed by coronary artery calcium (CAC) quantification in individuals without previous cardiovascular disease (CVD).

METHODS

We included 20 patients over 18 years of age with no history of CVD who underwent multiple detector-computed tomography. From each patient, a stool sample was obtained to characterize gut microbiota composition by sequencing bacterial 16S ribosomal RNA gene. In addition, circulating levels of TNF-α and IL-1β, as well as trimethylamine N-oxide (TMAO) were determined in plasma samples by automated ELISA and capillary gas chromatography-mass spectrometry, respectively.

RESULTS

The mean age of patients was 63.5 years and 60% were women. Half of patients had CAC >100 (Agatston score), and were characterized by a higher abundance of the phylum Proteobacteria, mainly of bacteria belonging to the families Enterobacteriaceae and than patients with a CAC ≤ 100. Moreover, bacterial genera identified as biomarkers, such as Enterobacter, Escherichia/Shigella y Klebsiella, were positively associated with inflammation levels and with TMAO production.

CONCLUSION

Our data shows a gut microbiota profile associated with the presence of coronary calcium in patients without previous CVD. Although there are no strategies to decrease the amount of coronary calcium, gut microbiota is highly malleable by several factors. The possibility of preventing and even intervening CVD progression through strategies targeted gut microbiota is a very attractive idea that deserves further studies.

Klotho expression in peripheral blood circulating cells is associated with vascular and systemic inflammation in atherosclerotic vascular disease

Cardiovascular disease is the leading cause of death worldwide. New therapeutic strategies are aimed to modulate the athero-inflammatory process that partially orchestrates underlying vascular damage. Peripheral blood circulating cells include different immune cells with a central role in the development of the atherogenic inflammatory response. The anti-aging protein α-Klotho has been related to protective effects against CVD. KL is expressed in monocytes, macrophages, and lymphocytes where it exerts anti-inflammatory effects. In this work, we analyse the relationships of the levels of inflammatory markers with the expression of the KL gene in PBCCs and with the serum levels of soluble KL in atherosclerotic vascular disease. For this, we conducted a cross-sectional single-center case–control study including a study group of 76 CVD patients and a control group of 16 cadaveric organ donors without medical antecedent or study indicating CVD. Vascular artery fragments and whole blood and serum samples were obtained during elective or organ retrieval surgery. Serum levels of sKL, TNFα and IL10, and gene expression levels of KL, TNF, IL10, NFKB1, DNMT1, and DNMT3A in PBCCs were measured. In these cells, we also determined KL promoter methylation percentage. Histological and immunohistochemical analyses were employed to visualize atherosclerotic lesions and to measure IL10 and TNFα levels in vascular fragments. Patients with CVD presented higher values of proinflammatory markers both at systemic and in the vasculature and in the PBCCs, compared to the control group. In PBCCs, CVD patients also presented lower gene expression levels of KL gene (56.4% difference, P < 0.001), higher gene expression levels of DNMT1 and DNMT3A (P < 0.0001, for both) and a higher methylation status of in the promoter region of KL (34.1 ± 4.1% vs. 14.6 ± 3.4%, P < 0.01). In PBCCs and vasculature, KL gene expression correlated inversely with pro-inflammatory markers and directly with anti-inflammatory markers. sKL serum levels presented similar associations with the expression levels of pro- and anti-inflammatory markers in PBCCs. The differences in KL expression levels in PBCCs and in serum sKL levels with respect to control group was even greater in those CVD patients with macroscopically observable atheromatous plaques. We conclude that promoter methylation-mediated downregulation of KL gene expression in PBCCs is associated with the pro-inflammatory status in atherosclerotic vascular disease.

Brachial-ankle pulse wave velocity with a custom device

BACKGROUND AND OBJECTIVES

The brachial-ankle pulse wave velocity (baPWV) is one of the most widely used arterial stiffness variables for assessing vascular risk. The abiPWV is a device that calculates various PWVs and the blood pressure ankle-brachial index (ABI). The device can also determine baPWV. The aim of this study was to calculate the baPWV with abiPWV, validate it with a reference device (VaSera) and study its clinical usefulness.

PATIENTS AND METHODS

We studied 113 patients (mean age, 53±12years), 59 (52%) of whom were women, and 10 (8.8%) of whom had a previous cardiovascular event. The participants were classified according to cardiovascular risk factors (CRFs) into groupI (none), groupII (1 or 2 CRFs) and groupIII (3 or more CRFs). The patients with a previous cardiovascular event were included in groupIII. All participants had their baPWV measured with abiPWV and VaSera.

RESULTS

The baPWV correlation between the 2 devices was r=0.93 (P<.001), and the percentage error calculated with the Bland-Altman analysis was 4.5%. The baPWV measured with abiPWV (in m/s) was as follows: groupI, 10.5±1.6; groupII, 13.8±2.9 (P<.001 when compared with groupI); and groupIII, 14.1±2.7 (P<.001 when compared with groupI). There were no differences between groupsII and III. The results with VaSera were comparable to those of abiPWV.

CONCLUSIONS

Measuring baPWV with the abiPWV is safe and has a similar clinical utility to that of VaSera. Incorporating this function into the options of abiPWV makes it a complete device for assessing arterial stiffness.

[Pulse wave velocity of the leg minus that of the arm measured with a custom device correlates to the coronary calcium quantification]

OBJECTIVE

The pulse wave velocity (PWV) in the great arteries is an indicator of vascular risk. Our objective was to identify the PWV index between the arms and legs that best correlates with the coronary calcium quantification (CCQ) and to compare it with other methods.

MATERIAL AND METHODS

Eight-one patients without vascular disease underwent the following measurements: CCQ; carotid intima-media thickness (IMT); carotid-femoral PWV (cfPWV), using COMPLIOR; and PWV in the arms and legs, with our own device (abiPWV, ankle brachial index PWV).

RESULTS

The difference in PWVs between the leg and arm (l-a PWV) measured with abiPWV was the index that best correlated with CCQ (r=0.401, P<.001). The correlation between IMT and CCQ and between CF-PWV and CCQ were r=0.366, P=.001; and r=0.385, P=.001, respectively. For a CCQ score higher than 100 as a marker of significant coronary arteriosclerosis, the areas under the curve for l-a PWV, IMT and cfPWV were 0.721 (P=.002), 0.758 (P<.001) and 0.636 (P=.058), respectively.

CONCLUSIONS

For patients without vascular disease, the l-a PWV measured with abiPWV appears to be the index that best correlates with the CCQ. This association is comparable to that between IMT and CCQ and between cfPWV and CCQ. The abiPWV is an easy-to-use device that can help improve vascular risk stratification.

Imaging subclinical atherosclerosis: is it ready for prime time? A review

Imaging subclinical atherosclerosis holds the promise of individualized cardiovascular (CV) risk assessment. The large arsenal of noninvasive imaging techniques available today is playing an increasingly important role in the diagnosis and monitoring of subclinical atherosclerosis. However, there is a debate about the advisability of clinical screens for subclinical atherosclerosis and which modality is the most appropriate for monitoring risk and atherosclerosis progression. This article offers an overview of the traditional and emerging noninvasive imaging modalities used to detect early atherosclerosis, surveys population studies addressing the value of subclinical atherosclerosis detection, and also examines guideline recommendations for their clinical implementation. The clinical relevance of this manuscript lies in the potential of current imaging technology to improve CV risk prediction based on traditional risk factors and the present recommendations for subclinical atherosclerosis assessment. Noninvasive imaging will also help to identify individuals at high CV who would benefit from intensive prevention or therapeutic interventions.

Growth patterns of abdominal atherosclerotic calcified deposits from lumbar lateral X-rays

The aim of this study is to investigate new methods for describing the progression of atherosclerosis based on novel information of the growth patterns of individual abdominal aortic calcifications (AACs) over time. Lateral X-ray images were used due to their low cost, fast examination time, and wide-spread use, which facilitates a large statistical model (n > 100) based on longitudinal data. The examined cohort consisted of 103 post-menopausal women aged 62.4 years (± 7.0 years) with an average number of AACs of (4.7 ± 8.0) at baseline. The subjects had X-ray images taken in 1992-1993 (baseline) and again in 2000-2001 (follow-up). The growth patterns of the individual AACs were derived based on registered baseline and follow-up images. Area, height, width, centre of mass position, and movement of the centre of mass, and upper and lower boundary of the matched AACs were measured. The AACs occurred first, mainly, on the posterior aortic wall. The AACs grew on average 41 in the longitudinal direction and 21 in the radial direction. A correlation of 0.48 (P < 0.001) between growth in width and height of the AACs was present. The centre of mass of the AACs moved 0.60 mm (P < 0.001) downstream in the aorta, on average. The growth patterns of AACs may give new insights into the progression of atherosclerosis. The downstream asymmetry in the growth patterns indicates variability in microscopic environments around the AACs.