Husain-Syed F, Birk HW, Ronco C, et al. - Given a crucial cause of adverse outcomes in heart failure is persistent congestion with worsening renal function, researchers intended to characterize novel approaches to assess renal congestion using Doppler ultrasonography. Participants were patients (n = 205) with suspected or prediagnosed pulmonary hypertension (PH) undergoing right heart catheterization. On all participants, renal Doppler ultrasonography was performed. Invasive cardiopulmonary hemodynamics, echocardiography, renal function, intra-abdominal pressure, and neurohormones and hydration status were also evaluated. They defined four spectral Doppler intrarenal venous flow patterns and a new renal venous stasis index (RVSI). RVSI was superior to individual intrarenal venous flow patterns with regard to outcome prediction, as suggested by receiver operating characteristic curves (areas under the curve: 0.789 and 0.761, respectively). RVSI was introduced as a conceptually novel and integrative Doppler index of renal congestion, and it offered further prognostic information to stratify PH for the propensity to develop right heart failure.