Via practica 3/2023

Platelet hyperaggregability during pregnancy – experiences of one centre

Purpose: Sticky platelet syndrome (SPS) is a less known prothrombotic thrombocytopathy with a common familial occurrence and an increased risk of venous thromboembolism, development of arterial thrombosis and pregnancy complications. It is defined by an increased aggregability of platelets after the addition of low concentrations of inductors of such aggregation – adenosine diphosphate and/or epinephrine. Therefore, in these patients, the antiplatelet treatment for thromboprophylaxis should be generally indicated. Moreover, in the case of the development of acquired changes in haemostasis during pregnancy, the addition of anticoagulant drugs ought to be considered. The main aim of this study was therefore the monitoring of the presence of acquired changes in haemostasis during pregnancy and targeted modification of antithrombotics according to the exact results of a particular patient. Material and methods: Authors processed the results of a model group of 61 patients with a history of thromboembolic and pregnancy complications, in which they evaluated anti-Xa activity for the low molecular weight heparin (LMWH), parameters of a blood count and changes of haemostasis including D-dimers, free protein S (PS) function, activity of a coagulation factor VIII (FVIII) and ProC Global ratio four times during pregnancy and one time after the postpartum period. Results and discussion: During pregnancy and postpartum period, platelet count was kept in the reference range, progressive elevation of the concentration of D-dimers and FVIII activity after the postpartum period were normalized, but PS function and levels of ProC Global as a screening test of haemostasis stayed below the reference range. Anti-Xa activity for LMWH was between 0.25–0.53 IU/ml – the levels that are normal or even slightly higher above the reference range for the prophylactic dose of LMWH. Conclusion: Termination of the administration of LMWH depends on the presence of changes of special haemostasis and in our study, it was realized individually with regards to the actual clinical condition and results of a particular patient. Additionally, in the case of SPS, the use of acetylsalicylic acid (ASA) is indicated continuously.

Keywords: at-risk pregnancy, special haemostasis, antithrombotic prophylaxis