Lege Artis Medicinae

[Actual questions of the longterm anticoagulant therapy]

SAS Géza

DECEMBER 15, 2015

Lege Artis Medicinae - 2015;25(11-12)

[In the last few years we have witnessed some changes in the area of the chronic oral anticoagulant therapy. The nomenclature of the anticoagulant drugs has been modified and concern has arisen about the possible vascular calcification in patients on long-term warfarin therapy. Because of the novelty of the “new” anticoagulants (dabigatran etc.) has been lost, instead of their previous acronym (NOAC) the DOAC (direct oral anticoagulants) term has been accepted for their marking. Experimental and clinical data suggested that vitamin K-antagonists (VKA) in addition to the coagulation factors disturb the production of other proteins, too. By inhibiting the matrix Gla protein (MGP), the chronic warfarin therapy promotes the calcification in media of the arteries as it was shown in women participating in routine mammography. However, the clinical importance of this observation is dubious, because the incidence of acute coronary events is not increased in cases of warfarin therapy in patients with atrial fibrillation. Notwith­standing, in addition to the bleeding complications we have to take into account of the possible harmful vascular calcification, too, at the indication of chronic coumarin therapy. Therefore, this therapy should be applied only in proper cases, such as non-valvular atrial fibrillation with a high risk of ischaemic stroke or unprovoked venous thromboembolic disease with a high risk of recurrence. The results of the Swedish anticoagulant register show that the efficacy and safety of the well-managed coumarin therapy may be superior to the treatments with DOACs. However, DOACs are indispensable in certain cases in which a previous “probe” coumarin treatment is unfounded.]

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