Renal ultrasonography predicts worsening renal function in patients with heart failure under tolvaptan administration

AimsRenal dysfunction in patients with chronic heart failure predicts a poor prognosis. Tolvaptan has a diuretic effect in patients with chronic kidney disease and heart failure without adverse effects on renal function. We aimed to determine the effects of tolvaptan and predictors of worsening renal function in patients with heart failure.Methods and resultsThis post hoc analysis was a sub-analysis of a single-centre prospectively randomized trial on the early and short-term tolvaptan administration. We enrolled 201 participants with decompensated heart failure between January 2014 and March 2019 (early group, n = 104; age: 79.0 +/- 12.8 years; late group, n = 97; age: 80.3 +/- 10.8 years). Renal ultrasonography was performed before and after the administration of tolvaptan. Urine output and oral water intake significantly increased during tolvaptan administration. The difference between water intake and urine volume increased during tolvaptan administration. Changes in body weight, blood pressure, heart rate, and estimated glomerular filtration rate (eGFR) in both groups were comparable. The changes in peak-systolic velocity (PSV), acceleration time (AT) of the renal arteries, and resistance index were comparable. The changes in PSV and end-diastolic velocity (EDV) of the interlobar arteries increased following tolvaptan administration (Delta max PSV: 0.0 +/- 14.8 cm/s before tolvaptan vs. 5.6 +/- 15.7 cm/s after tolvaptan, P = 0.002; Delta mean PSV: 0.4 +/- 12.3 vs. 4.9 +/- 12.7 cm/s, P = 0.002; Delta max EDV: -0.2 +/- 3.5 vs. 1.4 +/- 4.0 cm/s, P = 0.001; Delta mean EDV: -0.0 +/- 3.1 vs. 1.1 +/- 3.4 cm/s, P = 0.003). The renal artery AT was negatively correlated with the eGFR (Delta max AT: beta = -0.2354, P = 0.044; Delta mean AT: beta = -0.2477, P = 0.035).ConclusionsTolvaptan increased the PSV and EDV of the interlobar artery, which may mean tolvaptan increased renal blood flow. The renal artery AT may be a surrogate for worsening renal function.