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[Hereditary resistance to vitamin K antagonists. Apropos of a case]

F Paganelli1, J Conard, R Gelisse

  • 1Service de cardiologie, centre hospitalier universitaire Marseille-Nord.

Archives Des Maladies Du Coeur Et Des Vaisseaux
|July 20, 1999
PubMed

Insights

Hereditary resistance to vitamin K antagonists is a rare condition. This case highlights the importance of considering genetic factors when patients do not respond to these anticoagulant drugs.

Area of Science:

  • Pharmacology
  • Genetics
  • Internal Medicine

Background:

  • Vitamin K antagonists are crucial anticoagulants.
  • Resistance is typically acquired due to non-adherence, malabsorption, diet, or enzyme induction.
  • Rarely, resistance can be hereditary.

Observation:

  • A 43-year-old male patient with atrial fibrillation presented with resistance to vitamin K antagonists.
  • Plasma levels of the drug were high despite administration, suggesting poor drug efficacy.

Findings:

  • The patient exhibited hereditary resistance to vitamin K antagonists.
  • This genetic anomaly impacts drug response and management.

Implications:

  • Clinicians must be aware of hereditary vitamin K antagonist resistance.
  • Consideration of genetic factors is vital for effective anticoagulation therapy.

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