[Control of anticoagulant therapy with portable prothrombin time device in patients with mechanical heart valve prostheses: two-year follow-up].
BACKGROUND
Monitoring patients on oral anticoagulation is essential to prevent haemorrhage and recurrent thrombosis, but it is still difficult. We studied a group of 348 patients with mechanical heart valve prostheses to verify whether the use of a new portable prothrombin time device might improve the management of oral anticoagulant therapy.


METHODS
We used a new portable prothrombin time device to check the anticoagulation therapy in a group of 348 patients with mechanical heart valve prostheses to validate its results by comparing to routine I.N.R. determinations (28 pts) and verify its user-friendliness by a face-to-face interview. Furthermore, the incidence of haemorrhagic and thromboembolic events has been studied by a two-year follow-up.


RESULTS
Pearson correlation indicated an R2 = 0.9 between I.N.R. values determined by routine or by a new portable prothrombin time device. All patients agreed to replace the routine I.N.R. determinations with those by the new procedure, particularly female, young and those with usually difficult blood collections. During the two-year follow-up period, 21 haemorrhagic (2.6/100/patients/year) and 5 thromboembolic events (0.6/100/patients/year) occurred; but neither replaced valves' thrombi nor fatal events were found out.


CONCLUSIONS
I.N.R.s determined using a new portable prothrombin time device are convincing as routine determinations. Such new procedure improves the quality of life, and the therapeutical range of anticoagulation is maintained safer and longer than by routine determinations. These results suggest that the control of anticoagulation in patients to a set I.N.R. therapeutic range is improved by using portable prothrombin time device in expert anticoagulation clinics, such improvement may result in reducing mortality as well as morbidity in patients treated with oral anticoagulants.
Tretjak
Irene
I
Infermiere professionale Centro Cardiovascolare, Azienda Sanitaria Triestina.
Benvenuto
Gianna
G
Drigo
Franca
F
Casson
Michela
M
Barocchi
Giulio
G
Humar
Franco
F
Pivotti
Fulvio
F
Fisicaro
Maurizio
M
Giansante
Carlo
C
Scardi
Sabino
S
D000925:Anticoagulants / Q000627:therapeutic use*; D004864:Equipment and Supplies / Q000009:adverse effects / Q000592:standards*; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D006470:Hemorrhage / Q000209:etiology; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation; D011517:Prothrombin Time; D013927:Thrombosis / Q000188:drug therapy; D013997:Time Factors
D000925:Anticoagulants