Background. As it is uncertain whether excess adiposity promotes primarily concentric or eccentric left ventricular hypertrophy (LVH), we aimed to dete
To determine whether high-quality nurse-recorded auscultatory blood pressure (BP) values obtained at a single visit predict cardiovascular target organ changes as closely as ambulatory BP measurements. In a randomly selected population sample (n = 458, 21% receiving antihypertensive treatment; approximately 40% hypertensive), we compared high-quality single visit nurse-recorded auscultatory BP values to same-day 24-h ambulatory BP in their ability to predict multiple target organ changes [left ventricular mass index (LVMI), left ventricle (LV) mean wall thickness (MWT), early-to-late transmitral velocity ratios (E/A), (echocardiography); log of urinary albumin-to-creatinine ratios (log ACR) (24-h urine samples); large artery dysfunction [carotid-femoral pulse wave velocity (PWV) and central augmentation index (Alc) (applanation tonometry)]. Nurse-recorded systolic BP (SBP) measurements obtained at a single visit were as closely associated with LVMI (r = 0.44), LV MWT (r = 0.44), E/A (r = -0.55), log ACR (r = 0.20), PWV (r = 0.62) and AIc (r = 0.41) (P < 0.0001 for all relations) as was 24-h SBP (LVMI; r = 0.33, LV MWT; r = 0.37, E/A; r = -0.35, log ACR; r = 0.24, PWV; r = 0.41, and AIc; r = 0.18, P < 0.001 for all relations) and either day or night SBP. On multivariate regression analysis with both nurse-recorded SBP and 24-h SBP in the same model, nurse-recorded SBP was independently associated with LVMI (P = 0.006), LV MWT (P = 0.03), E/A (P < 0.02), PWV (P < 0.0001) and AIc (P = 0.0002), and 24-h SBP was independently and positively associated with log ACR (P < 0.005), and PWV (P = 0.01). One or more, high-quality single visit nurse-recorded auscultatory BP measurements may be equally as effective as ambulatory BP in predicting target organ damage in a population sample of African ancestry.
Central aortic blood pressure (BP; BPc) predicts outcomes beyond brachial BP. In this regard, the application of a generalized transfer function (GTF) to radial pulse waves for the derivation of BPc is an easy and reproducible measurement technique. However, the use of the GTF may not be appropriate in all circumstances. Although the peak of the second shoulder of the radial waveform (P2) is closely associated with BPc, and, hence, BPc may be assessed without the need for a GTF, whether P2-derived BPc is associated with adverse cardiovascular changes independent of brachial BP is uncertain. Thus, P2- and GTF-derived aortic BPs were assessed using applanation tonometry and SphygmoCor software. Left ventricular mass was indexed for height 1.7 (n=678) and carotid intima-media thickness (IMT; n=462) was determined using echocardiography and vascular ultrasound. With adjustments for nurse-derived brachial pulse pressure (PP), P2-derived central PP was independently associated with left ventricular mass indexed for height 1.7 (partial r =0.18; P <0.0001) and IMT (partial r =0.40; P <0.0001). These relations were similar to nurse-derived brachial PP-independent relations between GTF-derived central PP and target organ changes (left ventricular mass indexed for height 1.7 : partial r =0.17, P <0.0001; IMT: partial r =0.37, P <0.0001). In contrast, with adjustments for central PP, nurse-derived brachial PP-target organ relations were eliminated (partial r =−0.21 to 0.05). Twenty-four–hour, day, and night PP-target organ relations did not survive adjustments for nurse-derived brachial BP. In conclusion, central PP derived from P2, which does not require a GTF, is associated with cardiovascular target organ changes independent of brachial BP. Thus, when assessing adverse cardiovascular effects of aortic BP independent of brachial BP, P2-derived measures may complement GTF-derived measures of aortic BP.
Although indexes of wave reflection enhance risk prediction, the extent to which measures of aortic systolic pressure augmentation (augmented pressures [Pa] or augmentation index) underestimate the effects of reflected waves on cardiovascular risk is uncertain. In participants from a community sample (age >16), we compared the relative contribution of reflected (backward wave pressures and the reflected wave index [RI]) versus augmented (Pa and augmentation index) pressure wave indexes to variations in central aortic pulse pressure (PPc; n=1185), and left ventricular mass index (LVMI; n=793). Aortic hemodynamics and LVMI were determined using radial applanation tonometry (SphygmoCor) and echocardiography. Independent of confounders, RI and backward wave pressures contributed more than forward wave pressures, whereas Pa and augmentation index contributed less than incident wave pressure to variations in PPc ( P <0.0001 for comparison of partial r values). In those <50 years of age, while backward wave pressures (partial r =0.28, P <0.0001) contributed more than forward wave pressures (partial r =0.15, P <0.001; P <0.05 for comparison of r values), Pa (partial r =0.13, P <0.005) contributed to a similar extent as incident wave pressure (partial r =0.22, P <0.0001) to variations in LVMI. Furthermore, in those ≥50 years of age, backward wave pressures (partial r =0.21, P <0.0001), but not forward wave pressures ( P =0.98), while incident wave pressure (partial r =0.23, P <0.0001), but not Pa ( P =0.80) were associated with LVMI. Pa and augmentation index underestimated the effect of wave reflection on PPc and LVMI in both men and women. Thus, as compared with relations between indexes of aortic pressure augmentation and PPc or LVMI, strikingly better relations are noted between aortic wave reflection and PPc or LVMI.
1 December 2009 in The American Journal of Cardiology