Inflammation and reduced parasympathetic cardiac modulation in aortic-valve sclerosis

Abstract

Aortic-valve sclerosis increases cardiovascular mortality risk and precedes aortic-valve stenosis, but its mechanisms are not well understood. The purpose of this study was to compare the cardiac autonomic modulation and inflammation markers between subjects with aortic-valve normal leaflets and subjects with aortic-valve sclerosis. According to 2-D transthoracic echocardiograms, 61 middle-aged volunteers without chronic or acute illnesses were classified in two groups: with no aortic-valve sclerosis (NAVS, N = 16) and with aortic-valve sclerosis (AVS, N = 45). An electrocardiogram at the supine position and active standing was collected to estimate heart rate variability (HRV) indices. A blood sample was obtained to quantify markers of inflammation. Compared to NAVS, AVS subjects showed higher levels of IL-6 (1619 ± 650 vs. 1169 ± 676 pg/mL, p = 0.044) as well as TNFα (370.8 ± 182.0 vs. 247.3 ± 188.2 pg/mL, p = 0.032), and larger low-frequency (LF) to high-frequency (HF) ratio during supine position (Ln(LF/HF) = 0.85 ± 0.85 vs. 0.11 ± 0.69, p = 0.003). Multiple logistic regression analysis showed that AVS was independently associated with LF/HF, TNFα and left ventricle mass index (p < 0.05). In conclusion, a significant reduction of the parasympathetic-driven cardiac modulation and low-grade inflammation occurs in aortic-valve sclerosis.