TITLE: High-flow arteriovenous fistula is not associated with increased extracellular volume or right ventricular dysfunction in haemodialysis patients.

BACKGROUND: High-output congestive heart failure secondary to high-flow arteriovenous fistula (AVF) has been reported in haemodialysis (HD) patients. As high-flow AVF (HFA) would be expected to result in fluid retention, we conducted an observational study to characterize the relationship between AVF flow (Qa) and extracellular water (ECW) in HD patients.

METHODS: We measured Qa by ultrasound dilution in prevalent HD outpatients with an AVF in two dialysis centres. The ECW:total body water (TBW) ratio was measured both pre- and post-dialysis by multifrequency bioimpedance analysis. Transthoracic echocardiograms (TTEs) were performed as part of routine clinical management.

RESULTS: We included 140 patients, mean age 62.7 ± 15.7 years, 60.7% male, 47.9% diabetic and 22.9% with coronary revascularization. Mean Qa was 1339 ± 761 mL/min and 22 (15.7%) patients had HFA defined as Qa >2.0 L/min. Qa was positively associated with an upper arm AVF (P = 0.005), body mass index (P = 0.012) and N-terminal pro-brain natriuretic peptide (NT-proBNP) (P = 0.047) and negatively associated with diabetes (P < 0.001) and coronary revascularization (P = 0.005). The ECW:TBW ratio was positively associated with age (P < 0.001), Davies comorbidity index (P = 0.034), peripheral vascular disease (P = 0.030) and NT-proBNP (P = 0.002) and negatively associated with serum albumin (P < 0.001). Qa was not associated with the ECW:TBW ratio (P = 0.744). TTE parameters were not associated with Qa.

CONCLUSIONS: In our outpatient HD cohort, high AVF flow was not associated with ECW expansion, either pre- or post-dialysis when accounting for potential confounders. By controlling ECW, high access flow should not necessarily be perceived as a threat to cardiovascular physiology.

SOURCE: Jaques DA, Davenport A. High-flow arteriovenous fistula is not associated with increased extracellular volume or right ventricular dysfunction in haemodialysis patients[J]. Nephrol Dial Transplant, 2021, 36(3):536-543. DOI: 10.1093/ndt/gfaa188.

背景: 高流量动静脉瘘(AVF)继发的高输出量充血性心力衰竭在血液透析(HD)患者中已有报道。由于高流量AVF(HFA)可能导致液体潴留，我们进行了一项观察性研究，以确定HD患者AVF流量(Qa)和细胞外水(ECW)之间的关系。

方法：我们在两个透析中心用超声稀释法测定有动静脉内瘘的门诊HD患者的QA。用多频生物阻抗分析仪测定透析前后ECW/TBW的比值。作为常规临床治疗的一部分，进行了经胸超声心动图(TTES)检查。

结果：我们纳入140例患者，平均年龄62.76±15.7岁，其中男性60.7%，糖尿病患者47.9%，冠状动脉血运重建患者22.9%。平均Qa为1339±761mL/min，其中22例(15.7%)患者存在HFA（QA>2.0L/min）。QA与上臂AVF(P=0.005)、体重指数(P=0.012)、N-末端脑利钠肽原(NT-ProBNP)(P=0.047)呈正相关，与糖尿病(P<0.001)、冠状动脉血运重建(P=0.005)呈负相关。ECW/TBW比值与年龄(P<0.001)、Davies共病指数(P=0.034)、周围血管病变(P=0.030)、NT-ProBNP(P=0.002)呈正相关，与血清白蛋白呈负相关(P<0.001)。QA与ECW/TBW比值无相关性(P=0.744)。TTE参数与QA无关。

结论：在我们的HD门诊队列中，高AVF血流与ECW扩张无关，无论是透析前还是透析后，考虑到潜在的混杂因素。通过控制体外循环，高流量不应该被认为是对心血管生理的威胁。

启发：高流量AVF不一定导致液体潴留，但高流量可能让心脏的代偿功能下降，更易诱发心衰。