Blood pressure, arterial waveform, and arterial stiffness during hemodialysis and their clinical implications in intradialytic hypotension

This study included 152 hemodialysis patients (mean age, 69 years; 34.2% female) and investigated serial changes in blood pressure (BP) and arterial stiffness indices during hemodialysis using an oscillometric device, SphygmoCor XCEL, and examined whether assessment of the arterial waveform has clinical implications for the management of intradialytic hypotension (IDH). Measurement was performed every 30 min during hemodialysis, and the threshold defining IDH was systolic BP (SBP) decrease ≥40 mmHg or a requirement for antihypotensive medication in all patients and ≥ the 75th percentile of maximum SBP decrease during hemodialysis (≥34 mmHg) in the subgroup without antihypotensive medication ( n = 98). In all patients, a 1-standard deviation (SD) increase in the baseline subendocardial viability ratio (SEVR), an index of myocardial perfusion, was an independent predictor of IDH (odds ratio [OR] 0.43, p < 0.001). In the subgroup analysis, a serial change in SBP and all arterial waveform indices, including the augmentation index, augmented pressure (AP), and SEVR, during hemodialysis were greater for IDH than for non-IDH patients (all p < 0.01 by 2-way repeated-measures ANOVA), with the exception of heart rate ( p = 0.40) and diastolic pressure time index ( p = 0.21). Diabetes (OR 4.08), a 1-SD increase in ultrafiltration rate (OR 2.07), fractional shortening (OR 0.45), baseline SEVR (OR 0.36) and the first 1-h percent change in AP (OR 0.52) were independent predictors of IDH (all p < 0.05). In conclusion, impaired myocardial perfusion and increased arterial stiffness, particularly poor arteriolar responsiveness to acute dialysis-related changes, are associated with IDH, and predialysis SEVR evaluation can complement screening for IDH.