Abstract 10234: Independent Contribution of the Forward Pressure Wave to Aortic Blood Pressure and Left Ventricular Mass in Hypertension in Young-to-Middle Aged Adults
Introduction. Although antihypertensive agents modify the reflected wave component (augmentation pressure [AP]) of aortic pulse pressure (PPc), there is little evidence to support a beneficial effect of current agents on the aortic structural changes that determine the forward pressure wave (P1). Nevertheless, the contribution of P1 to increases in PPc in hypertension in young-to-middle aged adults is unknown.
Hypothesis. We assessed the hypothesis that P1 contributes to increases in PPc and left ventricular mass index (LVMI) in hypertension (HT) in young-to-middle aged adults.
Methods. Applanation tonometry was employed to determine aortic blood pressure (BP) in 1015 randomly recruited participants (age range=16-88years) from a community sample, 35.6% (n=361) of whom had HT with an elevated systolic BP (SBP). LVMI and stroke volume were determined using echocardiography.
Results. Independent of mean arterial pressure (MAP) and other confounders, both P1 and AP were independently related to PPc (partial r: P1=;0.91, AP=0.73) and central SBP (SBPc; partial r: P1=0.90, AP=0.70) in all participants (p<0.0001), but P1 accounted for a greater proportion of the variation in PPc and SBPc than AP (p<0.0001 for comparison of r values). Compared to normotensives (NT), hypertensives <43.8years of age (median age) had higher multivariate adjusted PPc (mmHg, HT=35±1, NT=28±1), SBPc (mmHg, HT=112±1, NT=107±1) and P1 (mmHg, HT=28±1, NT=21±1) (p<0.0001 for all), but not AP values (mmHg, HT=7.2±0.8, NT=6.3±0.2, p=0.33); whilst hypertensives >43.8years of age had increases in both P1 (mmHg, HT=31±1, NT=25±1, p<0.0001) and AP (mmHg, HT=16.6±0.4, NT=14.0±0.7, p<0.005). Neither augmentation index nor stroke volume accounted for the differences in PPc between HT and NT. P1 was independently associated with LVMI (partial r=0.14, p=0.01) and adjustments for P1 abolished PPc-LVMI relations (p=0.47).
Conclusions. Independent of steady-state pressures, P1 accounts for a considerable proportion of the increases in PPc and LVMI in hypertension in the young-to-middle aged. Thus, in the management of hypertension, therapy targeting the aortic structural changes that contribute toward P1 may be required in young-to-middle aged adults.
- © 2011 by American Heart Association, Inc.