Clinical Research in Cardiology

, Volume 101, Issue 6, pp 445–452

Frequency of heparin/platelet factor 4-dependent platelet antibodies in patients undergoing angioplasty and stenting for cardiovascular disease and their role for on-clopidogrel platelet reactivity

  • Thomas Gremmel
  • Karin Frühwirth
  • Christoph W. Kopp
  • Alexandra Kaider
  • Sabine Steiner
  • Tamam Bakchoul
  • Ulrich J. H. Sachs
  • Renate Koppensteiner
  • Simon Panzer
Original Paper

DOI: 10.1007/s00392-011-0411-3

Cite this article as:
Gremmel, T., Frühwirth, K., Kopp, C.W. et al. Clin Res Cardiol (2012) 101: 445. doi:10.1007/s00392-011-0411-3

Abstract

Background

The frequency of heparin-induced platelet antibodies (H/PF4 antibodies) following heparin exposure during percutaneous intervention with stent implantation is unknown. These antibodies may activate platelets and therefore contribute to high on-clopidogrel residual platelet reactivity (HRPR).

Methods

We screened 288 patients after angioplasty and stenting for H/PF4 antibodies by an IgG/A/M ELISA. The 44 (15.3%) positive samples were further evaluated for IgG only antibodies, by the particle gel immunoassay (PaGIA), the heparin induced platelet activation assay (HIPA) and MEA. Further, we determined on-treatment platelet reactivity by multiple electrode aggregometry (MEA) in these patients. In vivo platelet activation was assessed by P-selectin expression.

Results

The prevalence of H/PF4 antibodies in the total patients’ cohort was 15.3% (95% CI 11.3–20%) by the IgG/A/M ELISA, 9.4% (95% CI 6.3–13.4%) by the IgG ELISA, 11.5% (95% CI 8–15.7%) by PaGIA, 14.2% (95% CI 10.4–18.8%) by MEA, and 2.4% (95% CI 1–4.9%) by HIPA. On-treatment platelet reactivity was similar between patients without and with H/PF4 antibodies [39 AU (6–110 AU) vs. 41 AU (7–91 AU); P = 0.85]. HRPR was seen in 105 patients (37.5%), and occurred to a similar extent in patients without and with H/PF4 antibodies in all test systems (all P > 0.2). Further, there was no difference of the ELISA optical densities using the IgG/A/M or the IgG only ELISA between patients without or with HRPR (all P > 0.3). There was no significant difference of P-selectin expression between patients without or with H/PF4 antibodies (P = 0.97). Noteworthy, none of the patients who developed H/PF4 antibodies had heparin-induced thrombocytopenia or a thromboembolic event.

Conclusion

H/PF4 antibodies are not rare in patients undergoing angioplasty and stenting. However, these antibodies are not associated with the occurrence of HRPR.

Keywords

Heparin Platelet reactivity Clopidogrel 

Copyright information

© Springer-Verlag 2012

Authors and Affiliations

  • Thomas Gremmel
    • 1
  • Karin Frühwirth
    • 2
  • Christoph W. Kopp
    • 1
  • Alexandra Kaider
    • 3
  • Sabine Steiner
    • 1
  • Tamam Bakchoul
    • 4
  • Ulrich J. H. Sachs
    • 4
  • Renate Koppensteiner
    • 1
  • Simon Panzer
    • 2
  1. 1.Department of Internal Medicine IIMedical University of ViennaViennaAustria
  2. 2.Clinical Department for Blood Group Serology and Transfusion MedicineMedical University of ViennaViennaAustria
  3. 3.Core Unit for Medical Statistics and Informatics, Section of Clinical BiometricsMedical University of ViennaViennaAustria
  4. 4.Institute for Clinical Immunology and Transfusion MedicineJustus Liebig UniversityGiessenGermany