Clinical Applicability of an Intrarenal Venous Flow Analysis for the Diagnosis of Impaired 2 Hemodynamics regardless of the Chronic Kidney Disease Stage.

Objective　An intrarenal venous flow (IRVF) analysis is a noninvasive method for assessing renal venous congestion and elevated hemodynamic pressure; however, patients with a reduced renal function have been underrepresented in previous studies. We evaluated the usefulness of an IRVF analysis in diagnosing impaired hemodynamics in patients with chronic kidney disease (CKD).Patients or Materials　We retrospectively analyzed 228 patients hospitalized for heart failure who underwent renal Doppler ultrasonography, echocardiography, and right heart catheterization within 24 h during the stable phase. Patients were classified according to their estimated glomerular filtration rate (eGFR) into Group A (＜30 mL/min/1.73 m2), Group B (30-59 mL/min/1.73 m2), and Group C (≥60 mL/min/1.73 m2). The IRVF patterns were categorized as either continuous or discontinuous.Methods　Hemodynamic parameters assessed using right heart catheterization included the mean right atrial pressure (mRAP), mean pulmonary artery pressure (mPAP), mean pulmonary artery wedge pressure (mPAWP), and mean inferior vena cava pressure (mIVCP). The associations between IRVF patterns and hemodynamic parameters were analyzed, and a multivariate logistic regression analysis was performed to identify the independent predictors of discontinuous IRVF.Results　Discontinuous IRVF was observed in 65 patients (29%) and it was more frequent in those with lower eGFR. Across all CKD stages, patients with discontinuous IRVF had significantly higher mRAP, mPAP, and mPAWP than those with continuous IRVF. A multivariate analysis identified mRAP, mPAP, and moderate or greater tricuspid regurgitation as independent predictors of discontinuous IRVF.Conclusion　An IRVF analysis may be a useful noninvasive method for detecting impaired hemodynamics in patients with CKD, including those undergoing dialysis.