Use of the Platelet Reactivity Index by Grotemeyer, Platelet Function Analyzer, and Retention Test Homburg To Monitor Therapy with Antiplatelet Drugs

ABSTRACT

In 1974, Wu and Hoak described a method for determining circulating platelet aggregates. This method was modified by Grotemeyer in 1983.

The platelet reactivity index (PR) is based on the ratio of platelet aggregates in blood samples obtained in different buffer solutions. Platelet aggregates are resolved when blood is sampled in EDTA-buffer, but remain fixed when EDTA-formalin-buffer is used. Generally, the PR is preferred, because in vitro manipulations of platelets are not necessary, and the results are calculated. PR values above 1.05 are suspicious for elevated platelet aggregation. PR values above 1.2 indicate pathological changes in platelet aggregation. The PR is inexpensive (4.0 €) and rapid to perform.

PR values were used successfully to identify nonresponders to secondary prophylaxis with acetylsalicylic acid (ASA), that is, patients suffering from stroke (33%) and patients after cardiac ischemia (18%).

Furthermore, elevated PR values correlated significantly with the incidence of arterial thromboembolic complications. The PR correlated well in our prospective study with values received from the retention test Homburg (RT-H) and the platelet function analyzer (PFA-100).

The data indicate that the values of the PR seem to be highly predictive for the evaluation of the ASA therapy. However, the PR is not feasible for the determination of the ASA overdosage.

KEYWORDS

Platelet aggregation testing - platelet reactivity index (PR) - drug monitoring - ASA nonresponder

REFERENCES

• 1 Wu K K, Hoak J C. A new method for the quantitative detection of platelet aggregates in patients with arterial insufficiency.  Lancet. 1974;  2 924-926
• 2 Grotemeyer K H, Viand R, Beykirch K. Thrombozytenfunktion bei vasomotorischen Kopfschmerzen und Migränekopfschmerzen.  Dtsch Med Wochenschr. 1983;  108 775-778
• 3 Grotemeyer K H. The platelet reactivity test-a useful “by-product” of the blood sampling procedure?.  Thromb Res. 1991;  61 423-443
• 4 Koscielny J, Kiesewetter H, Jung F, Haass A. Hemodilution-New Aspects in the Management of Circulatory Blood Flow. Improvement of Macro- and Microcirculation. Berlin, Germany; Springer Verlag 1992: 198-200
• 5 Jung F, Bläsi U, Radtke H et al.. Plateletpheresis-induced increase in platelet reactivity using different cell separators.  Infusionsther Transfusionsmed. 1995;  22 237-243
• 6 Latza R, Koscielny J, Radtke H et al.. Platelet function in platelet concentrate during storage: comparison of two blood cell separators.  Transfusionsmedizin. 2000;  27 94-100
• 7 Alström T, Gräsbeck R, Hjelm M, Skandsen S. Recommendations concerning the collection of reference values in clinical chemistry and activity report.  Scand J Clin Lab Invest. 1975;  35 1-8
• 8 Wu K K, Hoak J C. Increased platelet aggregates in patients with transient ischemic attacks.  Stroke. 1975;  6 521-524
• 9 Trip M D, Cats V M, van Capelle F J, Vreeken J. Platelet hyperreactivity and prognosis in survivors of myocardial infarction.  N Engl J Med. 1990;  322 1549-1554
• 10 Grotemeyer K, Scharafinski H, Husstedt I W. Two-year follow-up of aspirin responder and aspirin non-responder. A pilot study including 180 post-stroke patients.  Thromb Res. 1993;  71 397-403
• 11 Bach R, Jung F, Kohsiek I et al.. Factors affecting the restenosis rate after percutaneous transluminal coronary angioplasty.  Thromb Res. 1994;  74 S55-67
• 12 Kundu S K, Heilmann E J, Sio R et al.. Description of an in vitro platelet function analyzer-PFA-100.  Semin Thromb Hemost. 1995;  21(suppl 2) 106-112
• 13 Andersen K, Hurlen M, Arnesen H, Seljeflot I. Aspirin non-responsiveness as measured by PFA-100 in patients with coronary artery disease.  Thromb Res. 2002;  108 37-42
• 14 Mueller T, Haltmayer M, Poelz W, Haidinger D. Monitoring aspirin 100 mg and clopidogrel 75 mg therapy with the PFA-100 device in patients with peripheral arterial disease.  Vasc Endovascular Surg. 2003;  37 117-123
• 15 Jilma B. Synergistic antiplatelet effects of clopidogrel and aspirin detected with the PFA-100 in stroke patients.  Stroke. 2003;  34 849-854
• 16 Wieding J U, Kostering H, Peine S et al.. Platelet retention test Homburg (RTH) and drug monitoring of platelet adhesive properties of von Willebrand factor.  Hämostaseologie. 2004;  24 217-220
• 17 Koscielny J, Meyer O, Kiesewetter H, Jung F, Latza R. Platelet reactivity index by Grotemeyer.  Hämostaseologie. 2004;  24 207-210
• 18 Zeiger F, Stephan S, Hoheisel G, Pfeiffer D, Ruehlmann C, Koksch M. P-selectin expression, platelet aggregates, and platelet-derived microparticle formation are increased in peripheral arterial disease.  Blood Coagul Fibrinolysis. 2000;  11 723-728
• 19 D'Souza D, Wu K K, Hellums J D, Phillips M D. Platelet activation and arterial thrombosis (grand round).  Lancet. 1994;  344 991-995