Retrospective comparison of standard clotting tests and novel clot waveform parameters in dogs using the turbidimetric ACL-TOP CTS 300 coagulation analyzer

Abstract

Clot waveforms are generated by coagulation analyzers, such as the ACL-TOP, that utilize photo-optical turbidimetric methods to measure prothrombin time (PT) and activated partial thromboplastin time (aPTT), which are standard clotting tests (SCTs). Additional quantitative clot waveform analysis (CWA) parameters include maximum velocity of the PT curve (PT1d), maximum acceleration of the aPTT curve (aPTT2d), and their change in optical density (ODdelta). We explored the potential for CWA to contribute unique information compared to SCTs and quantitative fibrinogen assay (QFA) in dogs with clinical indications for laboratory evaluation of coagulation. We retrospectively evaluated the frequency and agreement between normal, high, and low values of CWA and SCTs for 203 dogs relative to reference intervals (RIs). Most dogs had SCTs within RIs, but most CWA values were high regardless of whether SCT values were within, below, or above the RI. Agreement between SCTs and CWA was slight (kappa <30%). Clinically significant bleeding was noted in 28 of 203 (14%) dogs. SCTs were not different between bleeders and non-bleeders. Median QFA, PT1d, aPTTdelta, and aPTT2d values were statistically significantly higher than RIs in non-bleeders compared to bleeders, whose median values were not below RI. Compared with SCTs, CWA identified differences between the 2 groups. However, wide overlap between the 2 groups limits the use of CWA to clinically discriminate between bleeders and non-bleeders in a heterogeneous population of dogs. Further studies on the diagnostic utility of CWA in coagulopathic dogs are needed.

Diagnostic analysis of lupus anticoagulant using clot waveform analysis in activated partial thromboplastin time prolonged cases: A retrospective analysis

“…In this analysis, the optical solidification reaction waveform curve (ie, clotting curve) can be visualized using absorbance measurements. [4][5][6][7][8][9] Complex waveform analyses, which can be performed using ACL TOP software, have been used to evaluate the prognoses of patients with disseminated intravascular coagulation (DIC) and hemophilia. [10][11][12][13][14][15][16][17] In patients with APS, LA induces abnormal extension of the APTT, which suggests that the waveform would probably be distorted.…”

“…In this analysis, the optical solidification reaction waveform curve (ie, clotting curve) can be visualized using absorbance measurements 4‐9 . Complex waveform analyses, which can be performed using ACL TOP software, have been used to evaluate the prognoses of patients with disseminated intravascular coagulation (DIC) and hemophilia 10‐17 …”