Supplementary Material for: Changes in renal venous flow and liberation from renal replacement therapy in patients with acute heart failure

Introduction
In acute heart failure (AHF), the factors associated with successful renal replacement therapy (RRT) discontinuation are largely undefined. We hypothesized that improvements in Doppler-derived renal venous flow (RVF) waveforms may serve as indicators of recovering cardiorenal function associated with successful liberation from RRT.
Methods
We performed a post hoc analysis of a prospective cohort study involving inpatients with AHF undergoing serial renal Doppler evaluations. Patients who received acute RRT were retained for analysis, with Doppler assessments conducted both before RRT initiation and after discontinuation. Successful RRT discontinuation was defined as RRT cessation without relapse for at least 14 days. Logistic regression was used to evaluate the association between changes in RVF markers—including intra-renal venous flow (IRVF) and the renal venous stasis index (RVSI)—and RRT discontinuation, along with echocardiographic and clinical data from pre- to post-RRT Doppler measurements.
Results
10/53 (19%) patients successfully discontinued RRT. Increases in the severity of IRVF patterns and RVSI were negatively associated with RRT discontinuation (IRVF per 1-pattern increase in severity: OR 0.01, 95% CI: <0.001–0.11; P<0.001; RVSI per 0.1-unit increase: OR 0.11, 95% CI: 0.03–0.48; P<0.001). Additionally, improvements in right ventricular function markers, such as the TAPSE/sPAP ratio (per 0.1 mm/mm Hg increase: OR 1.83, 95% CI: 1.03–3.32; P=0.049), were associated with higher odds of RRT discontinuation.
Conclusions
In AHF patients requiring acute RRT, improvements in RVF were associated with successful RRT discontinuation. Serial RVF assessment may offer a noninvasive means of capturing dynamic changes in cardiorenal syndrome physiology and renal recovery. Larger studies with more frequent and appropriately timed Doppler assessments are needed to determine whether RVF monitoring may guide RRT management in AHF.

引言
在急性心力衰竭（acute heart failure, AHF）患者中，与肾脏替代治疗（renal replacement therapy, RRT）成功停用相关的危险因素尚未明确。本研究提出假说：多普勒衍生肾静脉血流（Doppler-derived renal venous flow, RVF）波形改善可作为与成功脱离肾脏替代治疗相关的心肾功能恢复的标志物。

方法
本研究对一项纳入接受系列肾脏多普勒评估的急性心力衰竭住院患者的前瞻性队列研究进行事后分析。纳入接受急性肾脏替代治疗的患者进行分析，分别在肾脏替代治疗启动前及停用后进行多普勒评估。肾脏替代治疗成功停用的定义为：停止治疗且至少14天内未出现病情复发。采用logistic回归分析评估肾静脉血流标志物（包括肾内静脉血流（intra-renal venous flow, IRVF）及肾静脉淤滞指数（renal venous stasis index, RVSI））的变化与肾脏替代治疗停用之间的关联，同时纳入肾脏替代治疗前后多普勒测量所得的超声心动图及临床数据。

结果
53例患者中10例（19%）成功停用肾脏替代治疗。肾内静脉血流分型严重程度及肾静脉淤滞指数的升高与肾脏替代治疗停用呈负相关（肾内静脉血流分型严重程度每升高1级：比值比（odds ratio, OR）0.01，95%置信区间（confidence interval, CI）：<0.001–0.11；P<0.001；肾静脉淤滞指数每升高0.1单位：OR 0.11，95%CI：0.03–0.48；P<0.001）。此外，右心室功能标志物（如三尖瓣环收缩期位移（Tricuspid Annular Plane Systolic Excursion, TAPSE）与收缩期肺动脉压（Systolic Pulmonary Artery Pressure, sPAP）的比值（TAPSE/sPAP ratio）每升高0.1 mm Hg：OR 1.83，95%CI：1.03–3.32；P=0.049）的改善与肾脏替代治疗停用的更高发生概率相关。

结论
在需要接受急性肾脏替代治疗的急性心力衰竭患者中，肾静脉血流改善与肾脏替代治疗成功停用相关。系列肾静脉血流评估可为捕捉心肾综合征生理变化及肾脏恢复的动态过程提供无创手段。未来仍需开展更大样本量、且多普勒评估频率与时机更合理的研究，以明确肾静脉血流监测是否可指导急性心力衰竭患者的肾脏替代治疗管理。