Applicability of Global Hemostatic Tools for Evaluation of Hemostatic State and Detection of Thrombosis in Cats With Cardiomyopathies

Background

Arterial thromboembolism (ATE) is a known complication of cardiomyopathies (CM) in cats. Hypercoagulability is believed to be one predisposing factor.

Objective

Assess applicability of global hemostatic tests for evaluating the systemic hemostatic state in cats with CM with concurrent ATE (CM + ATE).

Animals

Six cats with CM + ATE, 11 cats with CM, and 13 healthy cats.

Methods

Prospective case–control study (2016–2020). Echocardiography, whole blood thromboelastography (TEG), and thrombin generation testing (TGT) were performed. Hypercoagulability was defined for TEG as shortened reaction time (R), shortened kinetics (K), increased angle, or increased maximal amplitude and for TGT as decreased lag time, decreased time to peak, increased peak, or increased endogenous thrombin potential (ETP). If ≥ 1 parameter showed significant hypercoagulability compared with healthy cats, and no parameter showed significant hypocoagulability, the patient was considered hypercoagulable. The opposite criteria defined hypocoagulability.

Results

Hypocoagulability was detected for cats with CM + ATE compared with both cats with CM and healthy cats, characterized by significantly prolonged R and K on TEG as well as significantly increased time-to-peak and decreased peak and ETP on TGT. Additionally, some thrombocytopenia was considered likely in cats with CM + ATE, but could not be fully evaluated because of a high prevalence of concurrent platelet aggregation.

Conclusions and Clinical Importance

A systemic hypocoagulable state was detected in cats with CM with concurrent ATE. Similar hemostatic paradoxes in human patients with thrombosis have been suggested to be related to platelet exhaustion, local endocardial hypercoagulability, or alterations in regulatory proteins.