Acute effect of haemodialysis on endothelial function in patients with chronic renal failure.

LEPERA, ROSA M; MARAÑON RODRIGO; JOO TURONI CLAUDIO; SALINAS, JUAN; SANTOS, JUAN C; PERAL DE BRUNO MARIA

Río de Janeiro (Brasil)

Congreso; 07 World Congress of Nephrology; 2007

Sociedad Latinoamericana de Nefrología e Hipertensión

Introduction: There is controversy about acute effect of haemodialysis (HD) on endothelial function (EF). The EF may be assessed by flow-mediated dilatation in response to reactive hyperaemia (RH). On the other hand, elevated plasma levels of Von Willebrand factor (vWF) is a marker of endothelial dysfunction and is associated with cardiovascular mortality. In our laboratory we have adapted a plethysmographic method using photoelectric cell in order to measure the wave of arterial pulse in the finger. The aim of this study was to determine the influence of a HD session (pre- during and post-dialysis) on EF in patients with early-stage of chronic kidney diseases (ESCKD). For this intention we measure the RH by non-invasive assessment of the digital volume pulse and by vWF plasma levels.  Methods: From five hundred patients in HD of Fresenius Medical Care Tucumán, 16 patients (8 males, age 44±2 years) were selected according exclusion criteria: presence of diabetes, dyslipemia, uncontrolled hypertension cardiovascular or peripheral vascular disease. EF and plasma concentration of vWF was determined before, during (1h intradialysis) and after (1h) post-dialysis. The results were compared with age-matched healthy subjects. HR was expressed as the % of increase in the relation valley-peak (v-p) of wave of arterial pulse in mV. vWF plasma level was determined by ELISA and expresed as percentege [(OD-0.44)/0.0125]. Results: In both control subjects as well as patients we found presence of EF by RH (24±7, n=6 vs 14.6±3%, n=16; respectively p: NS). However, the plasma concentration of vWF was different in control vs patients (74±5; n=8 vs 92±2; n=16 respectively; p<0.001). Furthermore RH-response was improved during intradialysis period (postocclusion pre dialysis: 20±0.6; n=15 vs postocclusion intradyalisis: 22±0.8 mVolt; n=15; p<0.05). After dialysis only 3 patients remained with endothelial dysfunction. On the other hand, during HD session vWF values were diminished (∆=4.1±1.5; N=15; p<0.016). Finally after 1 h post dialysis, both v-p HR response and vWF plasma levels were recovered to initials values. Conclusion: Measurements of the response of wave of arterial pulse in the finger to RH demonstrated not only that EF was present in patients with ESCKD but also this response was improved during HD. Similarly, the decrease in vWF plasma levels could be indicating acute beneficial effects of dialysis. These finds are in agreement with previous works in which has been suggested that the damage of endothelium in chronic kidney diseases would not be due to acute effect of HD.