Last update:

   30-Oct-2001
 

Arch Hellen Med, 2000, 17(Supplement):110-114

ORIGINAL PAPER

Experience of monitoring patients in the anticoagulant therapy

�. MARAGKOS, �. BELLIA, �. DIGENOPOULOU, V. TSEVRENIS,
G. THEODOSIADIS, N. VGONTZA, A. GAFOU, E. NOMIKOU, A. LAGIANDREOU,
I. GEORGOPOULOS, A. KOUSOULAKOU, E. KONTOPOULOU-GRIVA
1st Blood Transfusion Center, Hippokration General Hospital of Athens, Greece


OBJECTIVE It is generally assumed that oral anticoagulant therapy requires frequent laboratory controls to assure therapeutic efficacy and to prevent life threatening adverse events. We performed this study in order to evaluate the therapeutic efficacy and the adverse events of our Anticoagulant Therapy Outpatient Clinic.
METHOD Our outpatient clinic began its activity in 1984 when we were treating 30 patients and we are now monitoring 850 of them. In 1998 we treated 578 outpatients with anticoagulant therapy. From those 371 patients had mechanical heart valves, 93 atrial fibrillation, 24 mitral or aortic valvular disease, 59 thrombosis, 11 congenital thrombophilia, 15 acquired thrombophilia and 5 pregnancy in high risk. Their follow up constituted of the history of their disease, laboratory testing with different thromboplastins (ISI: 1.0�1.03) and monitoring of the anticoagulant therapy. A special card of attendance was given to each one, as well as a book with instructions and precautions with a special report to food and drug interactions as well as to precautions during surgical and dental interventions or pregnancy. The therapeutic target INR for the patients with mechanical heart valves was 2.5�3.5, for those with arteriovenous bypass, atrial fibrillation, myocardial infraction, pulmonary embolism, and deep vein thrombosis (DVT) was 2�3 and for prevention of DVT 2�2.5. The prescribed anticoagulants were acenocoumarol or warfarin with or without aspirin and low molecular weight heparins in specific situations.
RESULTS The mean frequency of laboratory testing and monitoring of patients was three weeks with range 1�5 of weeks. The target INR was achieved in approximately 68�71% of our patients. In 1998 eight thrombotic events occured at INR lower than the therapeutic one, 14 bleeding events at INR higher and two severe bleeding episodes because of oral anticoagulants plus aspirin administration. Our results are in agreement with large clinical trials in the current literature.
CONCLUSIONS The efficacy of anticoagulant therapy necessitates a close control of the actual intensity of anticoagulation that requires both patient�s obedience and close monitoring by a specifically educated doctor in order to prevent life threatening adverse events. All of these are achieved in specialized anticoagulant therapy outpatient clinics, that must be organized at certain hospitals all over the country.

Key words: Adverse events, Anticoagulant therapy, Outpatient clinic.


� 2001, Archives of Hellenic Medicine