Department of Small Animal Clinical Sciences, Virginia-Maryland College of Veterinary Medicine, Blacksburg, Virginia, USA.
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, Tennessee, USA.
J Vet Intern Med. 2021 Nov;35(6):2636-2645. doi: 10.1111/jvim.16274. Epub 2021 Sep 30.
Hyperthyroid cats might have a predisposition to arterial thrombus formation. The mechanism for thrombogenesis currently is unknown but could be associated with systemic hypercoagulability as seen in hyperthyroid humans.
Our purpose was to evaluate markers of hemostasis in hyperthyroid cats compared to healthy cats, and in hyperthyroid cats before and after radioactive iodine treatment (RIT).
Twenty-five cats with hyperthyroidism and 13 healthy euthyroid cats >8 years of age.
Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration, antithrombin (AT), D-dimers, thrombin-antithrombin complexes (TAT), von Willebrand Factor antigen (vWF : Ag), and activity of factors VIII and IX were measured. An echocardiogram was performed in all cats. Hemostatic markers and echocardiogram were evaluated again 6 to 9 months after successful RIT in 7 cats.
Hyperthyroid cats had higher fibrinogen concentration (P < .0001), AT activity (P < .0001), and vWF : Ag concentration (P = .01) than healthy control cats with all results decreasing significantly post-RIT. Hyperthyroid cats were not more likely to be in a hypercoaguable state than euthyroid cats (P = .08). Serum T4 concentration was not a predictor of a hypercoagulable state (P = .53).
Hyperthyroid cats have evidence of altered hemostasis that does not appear to be solely attributable to cardiac abnormalities, but no evidence of a hypercoagulable state. Findings suggest altered hemostasis resolves after RIT. Hyperthyroid cats could have endothelial dysfunction as indicated by increased vWF : Ag which could potentiate thrombogenesis.
甲状腺功能亢进的猫可能容易发生动脉血栓形成。目前血栓形成的机制尚不清楚，但可能与甲状腺功能亢进患者中所见的全身性高凝状态有关。
我们的目的是评估甲状腺功能亢进的猫与健康猫之间、以及放射性碘治疗（RIT）前后甲状腺功能亢进的猫之间的止血标志物。
25 只患有甲状腺功能亢进的猫和 13 只年龄大于 8 岁的健康甲状腺功能正常的猫。
测定凝血酶原时间（PT）、活化部分凝血活酶时间（aPTT）、纤维蛋白原浓度、抗凝血酶（AT）、D-二聚体、凝血酶-抗凝血酶复合物（TAT）、血管性血友病因子抗原（vWF：Ag）和因子 VIII 和 IX 的活性。所有猫均进行超声心动图检查。在 7 只猫成功接受 RIT 后 6 至 9 个月，再次评估止血标志物和超声心动图。
甲状腺功能亢进的猫的纤维蛋白原浓度（P < 0.0001）、AT 活性（P < 0.0001）和 vWF：Ag 浓度（P = 0.01）高于健康对照组猫，所有结果在 RIT 后均显著降低。甲状腺功能亢进的猫与甲状腺功能正常的猫相比，发生高凝状态的可能性没有差异（P = 0.08）。血清 T4 浓度不是高凝状态的预测因素（P = 0.53）。
甲状腺功能亢进的猫有止血改变的证据，但似乎不仅仅归因于心脏异常，没有证据表明存在高凝状态。结果表明，RIT 后止血改变得到解决。甲状腺功能亢进的猫可能存在内皮功能障碍，表现为 vWF：Ag 增加，这可能增强血栓形成。
