Malik Jan, Valerianova Anna, Tuka Vladimir, Trachta Pavel, Bednarova Vladimira, Hruskova Zdenka, Slavikova Marcela, Rosner Mitchell H, Tesar Vladimir
Third Department of Internal Medicine, General University Hospital, First Faculty of Medicine, Charles University, U Nemocnice 1, Prague, 128 08, Czech Republic.
Department of Nephrology, General University Hospital, First Faculty of Medicine, Charles University, Prague, Czech Republic.
ESC Heart Fail. 2021 Jun;8(3):2165-2171. doi: 10.1002/ehf2.13305. Epub 2021 Mar 23.
High-flow arteriovenous fistula (AVF) for haemodialysis leads to profound haemodynamic changes and sometimes to heart failure (HF). Cardiac output (CO) is divided between the AVF and body tissues. The term effective CO (COef) represents the difference between CO and AVF flow volume (Qa) and better characterizes the altered haemodynamics that may result in organ hypoxia. We investigated the effects of Qa reduction on systemic haemodynamics and on brain oxygenation.
This is a single-centre interventional study. Twenty-six patients on chronic haemodialysis with high Qa (>1500 mL/min) were indicated for surgical Qa reduction for HF symptoms and/or signs of structural heart disease on echocardiography. The included patients underwent three sets of examinations: at 4 months and then 2 days prior and 6 weeks post-surgical procedure. Clinical status, echocardiographical haemodynamic assessment, Qa, and brain oximetry were recorded. All parameters remained stable from selection to inclusion. After the procedure, Qa decreased from 3.0 ± 1.4 to 1.3 ± 0.5 L/min, P < 0.00001, CO from 7.8 ± 1.9 to 6.6 ± 1.5 L/min, P = 0.0002, but COef increased from 4.6 ± 1.4 to 5.3 ± 1.4 L/min, P = 0.036. Brain tissue oxygen saturation increased from 56 ± 11% to 60 ± 9%, P = 0.001.
Qa reduction led to increased COef. This was explained by a decreased proportion of CO running through the AVF in patients with Qa > 2.0 L/min. These observations were mirrored by higher brain oxygenation and might explain HF symptoms and improved haemodynamics even in asymptomatic high Qa patients.
用于血液透析的高流量动静脉内瘘（AVF）会导致显著的血流动力学变化，有时还会引发心力衰竭（HF）。心输出量（CO）在AVF和身体组织之间分配。有效心输出量（COef）这一术语表示CO与AVF血流量（Qa）之间的差值，能更好地描述可能导致器官缺氧的血流动力学改变。我们研究了降低Qa对全身血流动力学和脑氧合的影响。
这是一项单中心干预性研究。26例慢性血液透析患者，其Qa较高（>1500 mL/min），因出现HF症状和/或超声心动图显示的结构性心脏病体征而接受手术降低Qa。纳入的患者接受了三组检查：分别在4个月时，以及手术前2天和手术后6周。记录临床状态、超声心动图血流动力学评估、Qa和脑血氧饱和度。从入选到纳入，所有参数均保持稳定。手术后，Qa从3.0±1.4降至1.3±0.5 L/min，P<0.00001，CO从7.8±1.9降至6.6±1.5 L/min，P = 0.0002，但COef从4.6±1.4升至5.3±1.4 L/min，P = 0.036。脑组织氧饱和度从56±11%升至60±9%，P = 0.001。
降低Qa导致COef增加。这可以解释为在Qa>2.0 L/min的患者中，流经AVF的CO比例降低。这些观察结果反映在较高的脑氧合上，这可能解释了即使在无症状的高Qa患者中出现的HF症状和血流动力学改善。
