title: Poor comparability of coagulation screening test with specific measurement in patients receiving direct oral anticoagulants: results from a multicenter/multiplatform study.
abstract: Essentials Prothrombin and partial thromboplastin time (PT/PTT) measure direct oral anticoagulants (DOACs). PT, PTT and specific tests for DOACs were performed on patients treated for atrial fibrillation. Normal PT/PTT don't exclude DOAC activity and their prolongation doesn't confirm DOAC action. The use of PT or PTT to evaluate DOAC activity could cause dangerous misinterpretations.
  
  
  
  Background Prothrombin time (PT) and activated partial thromboplastin time (APTT) have been proposed to measure the effect of oral anti-activated factor X (FXa) or anti-activated FII drugs, respectively. Aims To evaluate the relationships and responsiveness of PT and APTT versus direct oral anticoagulant (DOAC) concentrations measured with specific coagulation tests performed with different platforms in four Italian anticoagulation clinics. Methods Six hundred and thirty-five patients with atrial fibrillation participated in the study: 240 were receiving dabigatran, 264 were receiving rivaroxaban, and 131 were receiving apixaban. Blood was taken at trough and peak within the first month (15-25 days) of treatment. PT, APTT, diluted thrombin time (dTT) calibrated for dabigatran and anti-FXa calibrated for rivaroxaban or apixaban were determined. Results For dabigatran, the correlation between APTT and dTT ranged from r = 0.80 to r = 0.62. For rivaroxaban, the correlation between the anti-FXa assay and PT ranged from r = 0.91 to r = 0.73. For apixaban, the correlation between the anti-FXa assay and PT was lower than for the two other drugs (r = 0.81 to r = 0.54). Despite the above significant correlations, the responsiveness of PT or APTT was relatively poor. A discrepancy between global testing and DOAC plasma concentrations was shown in a considerable proportion of patients, depending on the platform and drug, with values ranging from 6% to 62%. Conclusions Overall, poor responsiveness of the screening tests to DOAC concentrations was observed. PT and APTT normal values cannot exclude DOAC anticoagulant activity, and PT or APTT prolongation is not always associated with DOAC anticoagulant effect as determined with specific tests.
authors: Department of Laboratory Medicine, Hemostasis and Thrombosis Center, AO Istituti Ospitalieri, Cremona, Italy.
authors: S
authors: S
authors: Testa
authors: Angiology and Blood Coagulation, University Hospital of Bologna, Bologna, Italy.
authors: C
authors: C
authors: Legnani
authors: Department of Clinical Sciences and Community Health, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Università degli Studi di Milano, IRCCS Cà Granda Maggiore Hospital Foundation, Milan, Italy.
authors: A
authors: A
authors: Tripodi
authors: Department of Laboratory Medicine, Hemostasis and Thrombosis Center, AO Istituti Ospitalieri, Cremona, Italy.
authors: O
authors: O
authors: Paoletti
authors: Department of Cardiothoracic and Vascular Sciences, University Hospital of Padua, Padua, Italy.
authors: V
authors: V
authors: Pengo
authors: Thrombosis Center, Department of Heart and Vessels, University Hospital of Florence, Florence, Italy.
authors: R
authors: R
authors: Abbate
authors: Department of Laboratory Medicine, Hemostasis and Thrombosis Center, AO Istituti Ospitalieri, Cremona, Italy.
authors: L
authors: L
authors: Bassi
authors: Department of Laboratory Medicine, ULSS 16 and University-Hospital of Padova, Padova, Italy.
authors: P
authors: P
authors: Carraro
authors: Angiology and Blood Coagulation, University Hospital of Bologna, Bologna, Italy.
authors: M
authors: M
authors: Cini
authors: Thrombosis Center, Department of Heart and Vessels, University Hospital of Florence, Florence, Italy.
authors: R
authors: R
authors: Paniccia
authors: Thrombosis Center, Department of Heart and Vessels, University Hospital of Florence, Florence, Italy.
authors: D
authors: D
authors: Poli
authors: Cardiovascular Diseases, University of Bologna, Bologna, Italy.
authors: G
authors: G
authors: Palareti
mesh_terms: D000284:Administration, Oral; D000925:Anticoagulants / Q000627:therapeutic use*; D000991:Antithrombins / Q000009:adverse effects; D001281:Atrial Fibrillation / Q000188:drug therapy*; D001777:Blood Coagulation / Q000187:drug effects; D001780:Blood Coagulation Tests / Q000379:methods; D002138:Calibration; D000069604:Dabigatran / Q000008:administration & dosage / Q000627:therapeutic use; D015951:Factor Xa / Q000737:chemistry; D065427:Factor Xa Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007558:Italy; D008297:Male; D010314:Partial Thromboplastin Time; D011517:Prothrombin Time; D011720:Pyrazoles / Q000008:administration & dosage / Q000627:therapeutic use; D011728:Pyridones / Q000008:administration & dosage / Q000627:therapeutic use; D012044:Regression Analysis; D000069552:Rivaroxaban / Q000008:administration & dosage / Q000627:therapeutic use; D013918:Thrombin Time; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants; D000991:Antithrombins; D065427:Factor Xa Inhibitors; D011720:Pyrazoles; D011728:Pyridones; C522181:apixaban; D000069552:Rivaroxaban; D015951:Factor Xa; D000069604:Dabigatran
keywords: activated partial thromboplastin time; anticoagulant drugs; atrial fibrillation; blood coagulation test; prothrombin time