Association of the trimethylamine N-oxide with cardiovascular risk and vascular alterations in middle-aged patients with risk factors for cardiovascular diseases.

BACKGROUND: Trimethylamine N-oxide (TMAO) is synthesized by the intestinal microbiota and is an independent predictor of cardiovascular disease (CVD). However, its underlying mechanisms remain unclear. We investigated TMAO levels across different CVD-risk patient groups, and evaluated associations between TMAO and vascular alterations (e.g., arterial stiffness, intima-media thickness [IMT], and the presence and grade of carotid artery plaques [CAPs]). METHODS: We examined 95 patients (58.5 ± 7.3 years): 40 with clinical atherosclerotic cardiovascular disease (ASCVD), 40 with atherosclerosis risk factors (RF), and 15 controls. Arterial stiffness was measured by Carotid-Femoral Pulse Wave Velocity (C-F PWV). B-mode ultrasound was used to evaluate the presence and grade of CAPs and carotid IMT (CIMT). TMAO was measured by high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) and results were presented as the median (interquartile range). RESULTS: TMAO levels were higher in patients with ASCVD (251.5 [164.5] µg/l) when compared with patients with RFs (194.0 [174] µg/l, P=0.04) and controls (122.0 (77) µg/l, P<0.001). A significant correlation was observed between TMAO and PWV (r = 0.31, P=0.003), which was not confirmed after adjustment for RFs. TMAO levels were significantly correlated with plaque score (r = 0.46, P<0.001) and plaque height (r=0.41, P=0.003), and were independent predictors for grade III plaques (odds ratio [OR] = 1.002, confidence interval (CI) 95%: 1.000047-1.003, P=0.044). CONCLUSIONS: TMAO levels are increased with expanded CVD risk. Across different types of vascular damage, TMAO is associated with atherosclerotic changes.

Torsion Mechanics as an Indicator of More Advanced Left Ventricular Systolic Dysfunction in Secondary Mitral Regurgitation in Patients with Dilated Cardiomyopathy: A 2D Speckle-Tracking Analysis.

Left ventricular (LV) twist serves as a compensatory mechanism in systolic dysfunction and its degree of reduction may reflect a more advanced stage of disease. AIM: The aim was to investigate twist alterations depending on the degree of functional mitral regurgitation (MR) by speckle-tracking echocardiography. METHODS: Sixty-three patients with symptomatic dilated cardiomyopathy (DCM) were included. Patients were divided according to MR vena contracta width (VCW): group 1 with VCW <7 mm (mild/moderate MR) and group 2 with VCW ≥7 mm (severe MR). RESULTS: There were no differences in LV geometry and function between groups. Group 2 showed lower endocardial basal rotation (BR) (-2.04° ± 1.83° vs. -3.23° ± 1.83°, p = 0.012); epicardial BR (-1.54° ± 1.18° vs. -2.31° ± 1.22°, p = 0.015); endocardial torsion (0.41°/cm ± 0.36°/cm vs. 0.63°/cm ± 0.44°/cm, p = 0.033) and mid-level circumferential strain (CSmid) (-6.12% ± 2.64% vs. -7.75% ± 2.90%, p = 0.028), when compared with group 1. Multivariable linear regression analysis identified endocardial BR, torsion and CSmid, as the best predictors of larger VCW. In the ROC curve analysis, endocardial BR and CSmid values greater than or equal to -3.63° and -9.35%, respectively, can differentiate patients with severe MR. CONCLUSIONS: In DCM patients, torsional profile was more altered in severe MR. Endocardial BR, endocardial torsion, and CSmid, can be used as indicators of advanced structural wall architecture damage.