PP.LB01.19

Abstract

Objective: Patients with atherosclerotic carotid disease usually do not present clinically overt signs of orthostatic dysregulation. In the present study we aimed at investigating if the presence of atherosclerotic plaque in the carotid sinus may alter baroreceptor function and thus heart rate variability (HRV) time-domain indices of autonomic tone and baroreflex sensitivity. Design and method: This was a cross-sectional study. We evaluated ECG R-R intervals in asymptomatic patients with carotid disease with an intima-media thickening (IMT) more than 0.8 mm. The atherosclerotic artery IMT was determined by B-mode and duplex ultrasonography. Baroreflex sensitivity and autonomic tone were determined through time-domain measures of HRV. Results: Of all time-domain measures of HRV investigated, we identified significant negative linear correlations between the common carotid artery IMT and time-domain HRV indexes reflecting baroreflex and autonomic tone: SDNN (standard deviation of R-R intervals), Spearman's r = −0.57, 95% CI: −0.78 to −0.25, P = 0.001; HRV triangular index (number of all R-R intervals / maximum number), Spearman's r = −0.62, 95% CI: −0.80 to −0.33, P = 0.0002; TINN (triangular interpolation of R-R intervals), Spearman's r = −0.59, 95% CI: −0.78 to −0.28, P = 0.0006. Similar strong negative correlations were found for subclavian IMT. Conclusions: Our data indicate that the SDNN, triangular index and TINN HRV biomarkers may be early predictors of atherosclerotic carotid and subclavian in subjects at risk and may be an indicator for ultrasound evaluation.