Abstract: Objective To investigate the correlation between pulmonary arterial hypertension (PAH) and vascular endothelial dysfunction in maintenance hemodialysis (MHD) patients. Methods We enrolled 60 MHD patients and assigned them into 2 groups, PAH group with pulmonary artery systolic pressure (PASP) > 35 mmHg, and non-PAH group with PASP <35 mmHg. Laboratory and clinical data were collected. Flow-mediated dilatation (FMD) was measured in brachial artery, and asymmetric dimethylarginine (ADMA) was measured at the mid-interdialysis day. Results Seventeen patients (28.3%) were diagnosed as PAH. Ratio of interval dialysis weight gain and dry weight (IDWG/DW) and high sensitivity C-reactive protein (hs-CRP) were significantly higher in PAH group than in non-PAH group (P＜0.05). After excluding other factors possibly related to endothelial dysfunction by analysis of covariance, FMD was 12.2±1.3% in PAH group, significantly higher than 6.9±1.2% in non-PAH group (F=63.8, P＜0.001), and ADMA was 2.97±0.31 μmol/L in PAH group, significantly higher than 2.10±0.29 μmol/L in non-PAH group (F=16.832, P＜0.01). Logistic regression revealed that left ventricular mass index (LVMI) (B=0.037, P=0.043) and ADMA (B=9.519, P=0.006) were the major factors for PAH. Conclusions PAH was significantly correlated with vascular endothelial dysfunction in MHD patients. LVMI and ADMA were the major factors for PAH.

Key words: Hemodialysis, Pulmonary hypertension,, Endothelial dysfunction, Flow-mediated dilation, Asymmetric dimethylarginine