Renal systolic time intervals derived from intra-renal artery Doppler as a novel predictor of adverse cardiac outcomes

Association of renal systolic time intervals with brachial-ankle pulse wave velocity

Aims: The renal systolic time intervals (STIs), including renal pre-ejection period (PEP), renal ejection time (ET), and renal PEP/renal ET measured by renal Doppler ultrasound, were associated with poor cardiac function and adverse cardiac outcomes. However, the relationship between renal hemodynamic parameters and arterial stiffness in terms of brachial-ankle pulse wave velocity (baPWV) has never been evaluated. The aim of this study was to assess the relationship between renal STIs and baPWV. Methods: This cross-sectional study enrolled 230 patients. The renal hemodynamics was measured from Doppler ultrasonography and baPWV was measured from ABI-form device by an oscillometric method. Results: Patients with baPWV ≧ 1672 cm/s had a higher value of renal resistive index (RI) and lower values of renal PEP and renal PEP/ET (all P< 0.001). In univariable analysis, baPWV was significantly associated with renal RI, renal PEP, and renal PEP/renal ET (all P< 0.001). In multivariable analysis, renal PEP (unstandardized coefficient β = -3.185; 95% confidence interval = -5.169 to -1.201; P = 0.002) and renal PEP/renal ET (unstandardized coefficient β = -5.605; 95% CI = -10.217 to -0.992; P = 0.018), but not renal RI, were still the independent determinants of baPWV. Conclusion: Our results found that renal PEP and renal PEP/renal ET were independently associated with baPWV. Hence, renal STIs measured from renal echo may have a significant correlation with arterial stiffness.