Estimated aortic blood pressure based on radial artery tonometry underestimates directly measured aortic blood pressure in patients with advancing chronic kidney disease staging and increasing arterial stiffness

Abstract

Central blood pressure (BP) can be assessed noninvasively based on radial tonometry and may potentially be a better predictor of clinical outcome than brachial BP. However, the validity of noninvasively obtained estimates has never been examined in patients with chronic kidney disease (CKD). Here we compared invasive aortic systolic BP (SBP) with estimated central SBP obtained by radial artery tonometry and examined the influence of renal function and arterial stiffness on this relationship. We evaluated 83 patients with stage 3 to 5 CKD (mean estimated glomerular filtration rate [eGFR] 30 ml/min/1.73 m(2)) and 41 controls without renal disease undergoing scheduled coronary angiography. BP in the ascending aorta was measured through the angiography catheter and simultaneously estimated using radial tonometry. The mean difference between estimated central and aortic SBP was -13.2 (95% confidence interval -14.9 to -11.4) mm Hg. Arterial stiffness was evaluated by carotid-femoral pulse wave velocity (cf-PWV) and was significantly increased in CKD patients compared with (versus) control patients (mean 10.7 vs. 9.3 m/s). The difference in BP significantly increased 1.0 mm Hg for every 10 ml/min decrease in eGFR and by 1.6 mm Hg per 1 m/s increase in cfPWV. Using multivariate regression analysis including both eGFR and cfPWV, the difference between estimated central and invasive aortic SBP was significantly increased by 0.7 mm Hg. For the entire cohort brachial SBP significantly better reflected invasive SBP than estimated SBP. Thus, tonometry-based estimates of central BP progressively underestimate invasive central SBP with decreasing renal function and increasing arterial stiffness in CKD patients.

Different Relevance of Peripheral, Central or Nighttime Blood Pressure Measurements in the Prediction of Chronic Kidney Disease Progression in Patients with Mild or No-Proteinuria

“…However, it has been recently shown, that in advancing CKD the tonometry-based method of measurement of CBP may underestimate the CBP values, mostly because the increased arterial stiffness [25, 26]. In our patients there was a significant increase of serum creatinine concentration found during the observation period, so it is possible that the advancing renal insufficiency might confound the accuracy of the measurement.…”

Subject-specific pulse wave propagation modeling: Towards enhancement of cardiovascular assessment methods

“…We found that the systolic pressure of the model simulated aortic wave was on average higher by 5 mmHg than the one reconstructed by SphygmoCor software from radial profiles. The problem of central systolic pressure underestimation when using PWA with generalized transfer function approach has been previously reported in the literature [ 44 , 45 ] (underestimation by 10–13 mmHg on average). This underestimation is typically attributed to the inaccuracies of the oscillometric brachial cuff measurements used in PWA for radial pulse waveform calibration, but our study suggests that at least some of this underestimation can be attributed to the inaccuracy of generalized transfer function itself.…”

Association of brachial and central hemodynamic parameters to eGFR and proteinuria in Gujarati diabetics with mild-to-moderate nephropathy

“…We found the same scenario in diabetics with than without antihypertensives in our previous studies on various cardiovascular parameters. [32021] 4) We did matching of subgroups by age and gender, and other confounders were also comparable, which was not the case in many other studies, 5) glycemic control was poor in most diabetics alike our previous studies[352021] and that overshadows other risk factors, 6) both BH and CH were measured simultaneously by same device, which is not so in tonometry-based devices,[22] which are used in most studies. 7) It was a cross-sectional design with moderate sample as opposed to vertical studies with large sample.…”