Abstract 269: Increased Vascular Age in Treated Hypertensive Patients With Elevated Augmentation Index
Background: Increased augmentation index has been considered a marker of arterial stiffness and a predictor of cardiac events.
Objective: To identify clinical and vascular parameters associated with increased augmentation index (Aix) in treated hypertensive patients.
Methods: A cross-sectional study was carried out to evaluate hypertensive patients on stable drug therapy over at least 4 weeks, both genders, aged 30-74 years. Blood pressure (BP), macro and microcirculation parameters were evaluated using high-resolution ultrasonography for brachial flow-mediated dilation (FMD), EndoPat 2000 for peripheral arterial tonometry and Sphygmocor to obtain Aix and other central hemodynamic parameters. The vascular age was also calculated after estimating Framingham risk score for general cardiovascular disease. Patients (n=177) were distributed into three equal groups (n=59 each) according to augmentation index values: 1st tertil (T1) AIx37%.
Results: The mean age was not different among the groups (55±11 vs 57±10 vs 58±8 years). Although similar diastolic BP was noted in the three groups (87±11 vs 90±13 vs 92±15 mmHg), T3 presented significant increase in brachial systolic BP (139±17 vs 145±17 vs 151±22 mmHg, p<0.006), aortic systolic BP (126±16 vs 138±17 vs 148±24 mmHg, p<0.001), and aortic pulse pressure (41±10 vs 49±14 vs 60±21 mmHg, p<0.001). Aix obtained in microcirculation by EndoPat (14±13 vs 30±19 vs 30±18 %, p<0.001) and vascular age (71±16 vs 77±13 vs 78±12 years, p=0.019) were significantly greater in T2 and T3 comparing to T1. There was no significant differences in endothelial function evaluated by brachial FMD (7.5±5.1 vs 8.9±5.5 vs 9.2±6.7 %) and through reactive hyperemia index by EndoPat (1.9±0.5 vs 2.2±0.7 vs 1.9±0.4 units). Aix was not correlated to age, but there was a significant correlation of Aix with vascular age (r=0.22, p=0.005), brachial systolic BP (r=0.208, p=0.006) and with aortic systolic BP (r=0.404, p<0.001).
Conclusion: In this population of treated hypertension, increased vascular stiffness characterized by an elevated augmentation index was associated to increased vascular age and raised brachial and aortic systolic BP but not with worsening of endothelial function.
- © 2012 by American Heart Association, Inc.