24 hour heart rate variability and atherosclerotic vascular damage

Introduction: The aim of this study is to analyse the relationship between the 24 hour heart rate variability and vascular structure and function in patients with cardiovascular risk factors. Methods: A descriptive, cross-sectional study was conducted on 301 patients (mean age 54 +/- 12 years, 61.8% males) with any risk factor. The 24 hour heart rate variability (DS_FC24 h) was assessed using an outpatient monitoring device. The rest of the variables were the carotid intima-media thickness (CIMT), measured by ultrasound, arterial stiffness with pulse-wave velocity (PWV), the ambulatory arterial stiffness index, and the haemodynamic parameters with the peripheral arterial pressure (PAIx) and central arterial pressure (CAIx) index. Results: All the parameters evaluated were higher in the first quartiles of the DS_FC24 h, with the exception of the PAIx, although the PWV did not reach statistical significance. There was a negative correlation between the DS_FC24 h and the mean CIMT (r = -0.271; P<.01), the PWV (r = -0.120; P<.05), AASI (r = -0,322; P<.01), PAIx (r = -0,122; P<.05 and CAIx (r = -0,248; P<.01). However, on adjusting for age the significance of the PWV and PAIx was lost. In the multiple regression models, only the CIMT, AASI, and the CAIx remained significant after the adjustments. Conclusion: The heart rate variability shows an inverse relationship with carotid intima-media thisckness, the ambulatory arterial stiffness index, and central augmentation index. The relationship with the pulse wave velocity and the peripheral augmentation index appears to be associated with age. (C) 2012 Elsevier Espana, S.L. and SEA. All rights reserved.