C68 resting Heart Rate and Arterial Stiffness: A Longitudinal Prospective Study in a Population of Hypertensive Patients

Objective The role of resting Heart Rate on the progression of arterial stiffness has not yet been extensively evaluated. The aim of this study is to investigate the relationship between resting HR and baseline arterial stiffness (evaluated by cfPWV) as well as its progression in a population of hypertensive patients over a 3.7 years follow–up period. Methods We enrolled 572 hypertensive outpatients 18–80 aged, followed by the Hypertension Unit of St. Gerardo Hospital (Monza, Italy). Anamnestic, clinical and laboratory data, BP and cfPWV (complior) were assessed at baseline and after a median follow–up time of 3.7 ± 0.5 years. Results At baseline the mean age was 53.9 ± 12.7 years, SBP and DBP were 141.2 ± 17.8 and 86.5 ± 10.5 mmHg, HR was 65.6 ± 10.9 bpm and PWV was 8.6 ± 2.0 m/s. Despite an improvement in BP values (from 141.2/86.5 to 132.6/79.2 mmHg, p < 0.001), during follow–up, PWV increased (ΔPWV 0.5 ± 2.2 m/s). In patients with a ΔHR above as compared to those under the median value (9 bpm), ΔPWV was significantly higher (0.82 ± 2.22 vs. 0.27 ± 2.25 m/s, p = 0.003). At multivariate analysis, HR was among the significant determinants of both baseline PWV and its progression (β = 0.031, p < 0.001). Furthermore, ΔHR was a significant determinant of ΔPWV (β = 0.019; p = 0.017). Conclusions In hypertensive patients there is a significant relationship between basal resting HR and basal PWV as well as between the increase of HR and the increase of PWV during the follow–up period. Beyond age and BP, resting HR must be considered as an independent determinant of arterial stiffness. This represents a possible mechanism through which HR contributes to the increase in CV risk.