title: Dielectric permittivity change detects the process of blood coagulation: Comparative study of dielectric coagulometry with rotational thromboelastometry.
abstract: BACKGROUND
  Intravascular thrombus formation causes various cardiovascular diseases. To monitor coagulation is important for screening native status, prevention from bleeding and maintaining it within its therapeutic range. The prothrombin time and the activated partial thromboplastin time are widely used for assessment and recognized as the conventional methods. Prothrombin time methods employ enhancement of coagulation with thromboplastin. Since the laboratory data depend on the production lot and/or the manufacturer, the accurate methods are required for evaluation. Rotational thromboelastometry (ROTEM) is a method based on detection of the change in resistance to rotational movement during blood clotting, while dielectric blood coagulometry (DBCM) is a novel method for assessment of clotting by measuring the change of electrical permittivity. These methods are thus based on the technology for observation of different physical phenomena. The aim of this study was to compare parameters such as the clotting time obtained by ROTEM and DBCM to evaluate their clinical usefulness.
  
  
  RESULTS
  ROTEM and DBCM parameters were measured in 128 patients. The ROTEM clotting time showed a significant positive correlation with the DBCM coagulation time (R=0.707, p<0.001). Comparison of the DBCM coagulation time between patients with and without anticoagulant therapy (including novel oral anticoagulants) revealed a significant difference (43.8±11.9min in the anticoagulant group vs 29.4±8.3min in the control group, p<0.001). Evaluation of coagulation was equivalent with DBCM and ROTEM.
  
  
  CONCLUSIONS
  The present study suggested that DBCM, a novel method for measuring blood clotting, could provide the detail assessment for the status of anticoagulant therapy.
authors.affiliation: Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Otaki
authors.affiliation: Life Science and Bioethics Research Center, Tokyo Medical and Dental University, Tokyo, Japan. Electronic address: ebnysk.bip@mri.tmd.ac.jp.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ebana
authors.affiliation: Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Shunji
authors.initials: S
authors.lastname: Yoshikawa
authors.affiliation: Department of Cardiovascular Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
mesh_terms: D001777:Blood Coagulation / Q000502:physiology*; D001780:Blood Coagulation Tests / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D013916:Thrombelastography / Q000379:methods*
keywords: Anticoagulant therapy; Coagulation; Dielectric blood coagulometry