Multiple Electrode Aggregometry (Impedance aggregometry)
Biochemistry
| Synonym | Thrombocytes Platelets |
|---|---|
| Half-life | 8 - 12 days |
| Synthesis | In bone marrow, as pluripotent bone marrow stem cells |
| Normal range | 150.000 - 400.000 per µl |
Thrombocytes are important for haemostasis and blood vessel repairs. They are also involved in inflammatory reactions. To perform these important tasks, platelets have the capability to interact with structures on the blood vessel walls. They adhere to the vessel wall and aggregate with each other, requiring certain stimuli to activate. In addition, cell surface receptors are required. Important receptors are the glycoproteins Ib/V/IX- and IIb/IIIa-complex.
Test principle of MEA
The Multiple Electrode Aggregometry (MEA) is a method for measuring the platelet function in whole blood. The electrical resistance, the impedance, is measured between two electrodes. After addition of different inducers the platelets adhere to the electrodes in the blood sample during the measurement. The impedance between the electrodes during the adherence and aggregation of the platelets is measured and graphically shown. The results are expressed in so-called aggregation units (AU).
Indication
Dual anti-platelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor (clopidogrel, prasugrel, ticagrelor) is the cornerstone in the treatment of acute coronary syndrome (ACS) and in percutaneous coronary intervention (PCI).
- Measuring therapeutic effects of certain medications (compliance)
- Support for the patient's individualized anti-platelet therapy
- Bleeding tendencies despite a normal thrombocyte count
- Support for diagnoses of diseases connected with thrombocytic dysfunction
- Control of acquired bleeding diseases after ingestion of certain medications
Literature
- Moenen FCJI, Vries MJA, Nelemans PJ, van Rooy KJM, Vranken JRRA, Verhezen PWM, Wetzels RJH, Ten Cate H, Schouten HC, Beckers EAM, Henskens YMC. Screening for platelet function disorders with Multiplate and platelet function analyzer. Int J Lab Hematol. 2015 Aug;37(4):503-8
- Albanyan A, Al-Musa A, AlNounou R, Al Zahrani H, Nasr R, AlJefri A, Saleh M, Malik A, Masmali H, Owaidah T Diagnosis of Glanzmann thrombasthenia by whole blood impedance analyzer (MEA) vs. light transmission aggregometry. J Thromb Haemost. 2017 Oct;15(10):2045-2052
- Al Ghaithi R, Drake S, Watson SP, Morgan NV,Harrison P. Comparison of multiple electrode aggregometry with lumi-aggregometry for the diagnosis of patients with mild bleeding disorders. Methods Mol Biol. 2017;1646:333-347
- Fritsma GA, McGlasson DL. Whole Blood Platelet Aggregometry. Haemophilia. 2019 May;25(3):e174-e179
- Nakajima Y, Nogami K, Yada K, Ogiwara K, Furukawa S, Shimonishi N, Shima M. Whole blood ristocetin-induced platelet impedance aggregometry does not reflect clinical severity in patients with type 1 von Willebrand disease. J Clin Med. 2020 Jan 24;9(2).
- Bélanger JC, Bandeira Ferreira FL, Welman M, Boulahya R, Tanguay JF, So DYF, Lordkipanidzé M.Head-to-Head Comparison of Consensus-Recommended Platelet Function Tests to Assess P2Y12 Inhibition-Insights for Multi-Center Trials. J Clin Med. 2020 Feb; 9(2): 332