Current Cardiology Reports

, Volume 5, Issue 2, pp 148–152 | Cite as

The selection of antithrombotic agents in the prevention of recurrent ischemic stroke

  • Cathy M. Helgason
Article
  • 26 Downloads

Abstract

The scientific selection of antithrombotic therapy has been dominated by group-based interpretation of data in the form of probability-based statistics in evidence-based medicine. Because the data in large randomized trials are grouped and averaged, the relationship to initial conditions of the patient is lost. There is a pathologic model and basis by which antithrombotic agents may be chosen for prevention of recurrent thrombus and thromboembolism in patients with stroke. This model applies in all settings, but has not been tested when the elements of the model remain connected to the individual patient and his or her unique context. Alternative math models and perception-based science respect the criticality of initial conditions and capture the rules that apply to the actual causal mechanisms within the patient's body. Individualized patient rather than group-based choices insure thrombus-type specific targeted therapy.

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References and Recommended Reading

  1. 1.
    Helgason CM, Malik DS, Cheng S-C, et al.: Statistical versus fuzzy measures of variable interaction in patients with stroke. Neuroepidemiology 2001, 20:77–84. This study shows that statistics based on probability theory cannot discern between real and fake patients. This is because the elements, called variables when numbers are attached to them, are separated from the patient's body physiology and natural context of interaction.PubMedCrossRefGoogle Scholar
  2. 2.
    Helgason CM, Watkins FA, Jobe TH: Measurable differences between sequential and parallel diagnostic decision processes for determining stroke subtype: a representation of interacting pathologies. Thromb Haemost 2002, 88:210–212. This study shows that the current subtyping of stroke is not defined according to pathophysiology, but rather to fit the mathematical model of probability-based statistics. It therefore does not reflect the complexity of natural interactions in nature.PubMedGoogle Scholar
  3. 3.
    Heemskerk JWM, Bevers EM, Lindhout T: Platelet activation and blood coagulation. Thromb Haemost 2002, 88:186–193. A major review of the interaction of platelets and the coagulation factors that emphasizes the complexity of interaction.PubMedGoogle Scholar
  4. 4.
    Helgason CM, Jobe TH: Necessary and sufficient causal ground and effect is measured by fuzzy cardinality and may represent natural edge strength connections in a clinical fuzzy cognitive map. North American Fuzzy Information Processing Society-Flint 2002 International Conference Proceedings. Piscataway, NJ: Institute of Electrical and Electronic Engineers Publication 02TH8622:117–123. This paper provides a new model for causation in medicine.Google Scholar
  5. 5.
    Kirchhof K, Welzel T, Zoubaa S, et al.: New method of embolus preparation for standardized embolic stroke in rabbits. Stroke 2002, 33:2329–2333. This paper reviews the difference between red and white thrombi.PubMedCrossRefGoogle Scholar
  6. 6.
    Sixth American College of Chest Physicians Consensus Conference on Antithrombotic Therapy. The American College of Chest Physicians. Chest 2001, 119(Suppl).Google Scholar
  7. 7.
    Camerlingo M, Casto L, Censori B, et al.: Immediate anticoagulation with heparin for first ever ischemic stroke in the carotid artery territories observed within 5 hours of onset. Arch Neurol 1994, 51:462–467. This paper is a positive study for heparin in acute stroke. It is little known and never quoted, but it is out there.PubMedGoogle Scholar
  8. 8.
    Simon RP, Powers WJ: Debate: anticoagulation in acute ischemic stroke: not indicated. In Cerebrovascular Disease: Momentum at the End of the Second Millenium. Edited by Choi D, Dacey R, Hsu C, Powers W. Armonk, NY: Futura Publishing; 2001:277–287.Google Scholar
  9. 9.
    Helgason CM, Tortorice KL, Winkler SR, et al.: Aspirin response and failure in cerebral infarction. Stroke 1993, 24:345–350.PubMedGoogle Scholar
  10. 10.
    Helgason CM, Bolin KM, Hoff JA, et al.: Development of aspirin resistance in persons with previous ischemic stroke. Stroke 1994, 25:2331–2336.PubMedGoogle Scholar
  11. 11.
    Helgason CM, Hoff JA, Kondos GT, Brace LD: Platelet aggregation studies in patients with atrial fibrillation on aspirin or coumadin. Stroke 1993, 24:1458–1461.PubMedGoogle Scholar
  12. 12.
    Grotemeyer KH, Scharafinski HW, Husstedt IW: 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.PubMedCrossRefGoogle Scholar
  13. 13.
    Eikelboom JW, Hirsh J, Weitz JI, et al.: Aspirin resistant thromboxane biosynthesis and the risk of myocardial infarction, stroke or cardiovascular death in patients at high risk for cardiovascular events. Circulation 2002, 105:1650–1655.PubMedCrossRefGoogle Scholar
  14. 14.
    Mohr JP, Thompson JL, Lazar RM, et al.: A comparison of warfarin and aspirin for the prevention of recurrent ischemic stroke. N Engl J Med 2001, 345:1444–1451.PubMedCrossRefGoogle Scholar
  15. 15.
    Mas J-L, Arquizan C, Lamy C, et al., for the Patent Foramen Ovale and Atrial Septal Aneurysm Study Group:Recurrent cerebrovascular events associated with patent foramen ovale, atrial septal aneurysm, or both. N Engl J Med 2001, 345:1740–1746.PubMedCrossRefGoogle Scholar
  16. 16.
    Hurlen M, Abdelnoor M, Smith P, et al.: Warfarin, aspirin, or both after myocardial infarction. N Engl J Med 2002, 347:969–974.PubMedCrossRefGoogle Scholar
  17. 17.
    van Es RF, Jonker JJ, Verheugt FW, et al., and the Antithrombotics in the Secondary Prevention of Events in Coronary Thrombosis-2 (ASPECT-2) Research Group: Aspirin and coumadin after acute coronary syndromes (the ASPECT-2 Study): a randomized controlled trial. Lancet 2002, 360:109–113.PubMedCrossRefGoogle Scholar
  18. 18.
    Caplan LR: Debate: heparin should be used to treat patients presenting with acute stroke or stroke-in evolution. Affirmative position. In Cerebrovascular Disease: Momentum at the End of the Second Millennium. Edited by Choi D, Dacey RG, Hsu CY, Powers WJ. Armonk, NY: Futura Publishing; 2002:269–277.Google Scholar
  19. 19.
    Brace LD, Jobe TH, Helgason CM: Variability of free protein S levels during the chronic phase of ischemic stroke. J Neurovascular Disease 1997, 2:182–188.Google Scholar
  20. 20.
    Muller I, Massberg S, Zierhut W, et al.: Effects of aspirin and clopidogrel versus oral anticoagulation on platelet function and on coagulation in patients with nonvalvular atrial fibrillation (CLAFIB). Pathophysiol Haemost Thromb 2002, 32:16–24.PubMedCrossRefGoogle Scholar
  21. 21.
    Aronow WS: Atrial fibrillation. Heart Dis 2002, 4:91–101.PubMedCrossRefGoogle Scholar
  22. 22.
    Fiske WD, Connell JM, Benedek IH: Lack of pharmacokinetic interaction between aspirin and warfarin. Am J Ther 1995, 2:407–413.PubMedGoogle Scholar
  23. 23.
    Hacke W: From cure to match: ADP receptor antagonists as the treatment of choice for high-risk atherothrombotic patients. Cerebrovasc Dis 2002, 13:22–26.PubMedCrossRefGoogle Scholar
  24. 24.
    Bhatt DL, Kapadia SR, Bajzer CT, et al.: Dual antiplatelet therapy with clopidogrel and aspirin after carotid artery stenting. J Invasive Cardiol 2001, 13:767–771.PubMedGoogle Scholar
  25. 25.
    O'Connor CM, Gattis WA, Hellkamp AS, et al.: Comparison of two aspirin doses on ischemic stroke in post-myocardial infarction patients in the warfarin (Coumadin) Aspirin Reinfarctioin Study (CARS). Am J Cardiol 2001, 88:541–546.PubMedCrossRefGoogle Scholar
  26. 26.
    Machroaoui A, Germing A, Lindstaedt M, et al.: Efficacy and safety of ticlopidine monotherapy versus ticlopidine and aspirin after coronary stenting: follow-up results of a randomized study. J Invasive Cardiol 2001, 13:431–436.Google Scholar
  27. 27.
    Easton JD: Future perspectives for optimizing oral antiplatelet therapy. Cerebrovasc Dis 2001, 11(Suppl 2):23–28.PubMedCrossRefGoogle Scholar
  28. 28.
    Atalar E, Aytemir K, Haznedarouglu I, et al.: Platelet and leukocyte deactivation after intracoronary stent placement in patients receiving combined antiplatelet therapy. Clin Appl Throm Hemost 2001, 7:116–121.Google Scholar
  29. 29.
    The Organization to Assess Strategies for Ischemic Syndromes (OASIS) Investigators: Long-term oral anticoagulation in patients with unstable angina or suspected non Q wave myocardial infarction. Circulation 1998, 98:1064–1070.Google Scholar
  30. 30.
    Rauch U, Osende JI, Fuster V, et al.: Thrombosis formation on atherosclerotic plaques: pathogenesis and clinical consequences. Ann Intern Med 2001, 134:224–238.PubMedGoogle Scholar
  31. 31.
    Stein PD, Alpert JS, Bussey HI, et al.: Antithrombotic therapy in patient s with mechanical and biological prosthetic heart valves. Chest 2001, 119(Suppl):220S-227S.PubMedCrossRefGoogle Scholar
  32. 32.
    Li-Saw-Hee FL, Blann AD, Lip GY: Effects of fixed low dose warfarin, aspirin warfarin combination therapy and dose adjusted warfarin on thrombogenesis in chronic atrial fibrillation. Stroke 2000, 31:828–833.PubMedGoogle Scholar
  33. 33.
    Lenz TL, Hilleman DE: Aggrenox: a fixed dose combination of aspirin and dipyridamole. Ann Pharmacother 2000, 34:1283–1290.PubMedCrossRefGoogle Scholar
  34. 34.
    Bhatt DL, Kapadia SR, Yadav JS, Topol EJ: Update on clinical trials of antiplatelet therapy for cerebrovascular diseases. Cerebrovascular Dis 2000, 10(Suppl 5): 34–40.CrossRefGoogle Scholar
  35. 35.
    Sabatine MS, Tu TM, Jang IK: Combination of a direct thrombin inhibitor and a platelet glycoprotein IIB/IIIa blocking peptide facilitates and maintains reperfusion of platelet-rich thrombus with alteplase. J Thromb Thrombolysis 2000, 10:189–196.PubMedCrossRefGoogle Scholar
  36. 36.
    Moshfegh K, Redondo M, July F, et al.: Antiplatelet effects of clopidogrel compared with aspirin after myocardial infarction: enhanced inhibitory effects of combination therapy. J Am Coll Cardiol 2000, 36:699–705.PubMedCrossRefGoogle Scholar

Copyright information

© Current Science Inc. 2003

Authors and Affiliations

  • Cathy M. Helgason
    • 1
  1. 1.University of Illinois at ChicagoChicagoUSA

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