RESUMEN
BACKGROUND: Thrombocytopenia is a possible risk factor for bleeding after band ligation of esophageal varices. However, elevated von Willebrand factor (VWF) in cirrhosis improves platelet function and could decrease this risk. Our objective was to assess platelet function in patients with cirrhosis undergoing esophageal variceal ligation (EVL). METHODS: The assessment consisted of platelet count, antigen and activity of VWF and VWF-cleaving protease ADAMTS-13 activity, and a platelet adhesion and aggregation test simulating vascular flow in vivo (Impact-Râ) prior to EVL. RESULTS: Totally 111 patients were divided into three groups according to platelet count: (1) < 50 × 109/L (n = 38, 34.2%); (2) 50 × 109/L to 100 × 109/L (n = 47, 42.3%); and (3) > 100 × 109/L (n = 26, 23.4%). No statistically significant difference was found in the aggregate size of platelets [group 1: 41.0 (31.8-67.3) µm2; group 2: 47.0 (33.8-71.3) µm2; and group 3: 47.0 (34.0-66.0) µm2; P = 0.60] and no significant correlation was found between aggregate size and platelet count (Spearman r = 0.07; P = 0.47). Surface coverage was 4.1% (2.8%-6.7%), 8.5% (4.0%-10.0%), and 9.0% (7.1%-12.0%) (P < 0.001) in groups 1, 2 and 3, respectively and correlated with platelet count (Spearman r = 0.39; P < 0.0001). There was no significant difference between groups in VWF or ADAMTS-13. Post-EVL bleeding occurred in six (5.4%) patients (n = 2 in group 1, n = 1 in group 2, and n = 3 in group 3; P = 0.32). Patients with bleeding had higher MELD scores [15.0 (11.3-20.3) versus 12.0 (10.0-15.0); P = 0.025], but no difference was demonstrated for platelet function parameters. CONCLUSION: Platelet function is preserved even in the presence of thrombocytopenia, including in the patients with post-EVL bleeding.
