After subject-specific blood pressure normalization, local carotid pulse wave velocity did not differ significantly between patients with mild hypertension and healthy controls (6.03 vs 5.80 m/s, p=0.47).
Cross-Sectional (n=44)
No
Does subject-specific pressure normalization of local pulse wave velocity eliminate the apparent difference in carotid stiffness between mild-to-moderate hypertensive patients and normotensive controls?
Subject-specific pressure normalization reveals that mild hypertension does not significantly alter intrinsic carotid artery stiffness independent of acute blood pressure differences.
Absolute Event Rate: 6.03% vs 5.8%
p-value: p=0.47
Pulse wave velocity (PWV) is a powerful predictor of cardiovascular events. However, its intrinsic blood pressure (BP)-dependency complicates distinguishing between acute and chronic effects of increased BP on arterial stiffness. Based on the assumption that arteries exhibit a nearly exponential pressure-area ( P - A ) relationship, this study proposes a method to assess intersubject differences in local PWV independently from BP. The method was then used to analyze differences in local carotid PWV (cPWV) between hypertensive and healthy normotensive people before and after BP-normalization. Pressure ( P ) and diameter ( D ) waveforms were simultaneously acquired via tonometer at the left and ultrasound scanning at right common carotid artery (CCA), respectively, in 22 patients with Grade 1 or 2 hypertension and 22 age- and sex-matched controls. cPWV was determined using the D 2 P -loop method. Then, the exponential modeling of the P -area ( A = π D 2 /4) relationships allowed defining a mathematical formulation to compute subject-specific changes in cPWV associated with BP changes, thus enabling the normalization of cPWV against intersubject differences in BP at the time of measurement. Carotid systolic BP (SBP) and diastolic BP (DBP) were, on average, 17.7 ( p 0.001) and 8.9 mmHg ( p 0.01) higher in hypertensives than controls, respectively. cPWV was 5.56 ± 0.86 m/s in controls and 6.24 ± 1.22 m/s in hypertensives. BP alone accounted for 68% of the cPWV difference between the two groups: 5.80 ± 0.84 vs. 6.03 ± 1.07 m/s after BP-normalization ( p = 0.47). The mechanistic normalization of cPWV was in agreement with that estimated by analysis of covariance (ANCOVA). In conclusion, the proposed method, which could be easily implemented in the clinical setting, allows to assess the intersubject differences in PWV independently of BP. Our results suggested that mild hypertension in middle-aged subjects without target organ damage does not significantly alter the stiffness of the CCA wall independently of acute differences in BP. The results warrant further clinical investigations to establish the potential clinical utility of the method.
Giudici et al. (Tue,) conducted a cross-sectional in Hypertension (n=44). Mild-to-moderate hypertension vs. Healthy normotensive controls was evaluated on Blood pressure-normalized local carotid pulse wave velocity (cPWV) (p=0.47). After subject-specific blood pressure normalization, local carotid pulse wave velocity did not differ significantly between patients with mild hypertension and healthy controls (6.03 vs 5.80 m/s, p=0.47).