Introduction

Feline aortic thromboembolism (FATE) is the sudden migration of thrombus into the aorta. While tissue plasminogen activator (TPA) improves outcomes in many thromboembolic diseases in people, outcome improvement has not been demonstrated in FATE, possibly due to sample size. Our study leverages a large retrospective caseload to compare outcomes in FATE treated with or without thrombolysis.

Methods

Multicenter, retrospective study from 2 French multispecialty hospitals (Fregis Veterinary Hospital and Lyon—VetAgroSup) between 2005 and 2020. Inclusion criteria were a diagnosis of FATE with ≥2 limbs affected, based on 5 criteria: pale, cold, pulselessness, painful and paralysis, and/or ultrasonographic visualization of thrombi. Exclusion criteria were missing data or enrollment in another FATE trial. TPA-treated cats were compared to no-TPA cats. Primary study outcomes were arterial recanalization and functional recovery. Secondary outcomes were survival to discharge and complication rates. After excluding cats euthanized at admission, statistical analysis of recanalization, functional recovery, survival proportions, post-treatment creatinine and potassium were performed. Continuous variables and categorical variables were analyzed using t-test combined with Levene test for variance, or Fisher’s exact test respectively.

Results

One hundred fifty-eight cats were included (52 TPA-treated cats and 106 no-TPA cats), with a mean age of 7.7±4.2 years. There was no significant difference in demographic and clinical data at admission between groups. Euthanasia proportion at admission was 24%, higher for Lyon-VetAgroSup compared to Fregis (53% vs. 15%, p=0.001). A total of 121 cats was left for further analysis: 56 TPA-treated and 65 in the no-TPA group. Median time-from-event-to-TPA was 3.8±1.5 hours. TPA protocol was 1 mg/kg intravenous over 1 hour. Arterial recanalization proportion was higher in TPA-treated than in no-TPA cats (54.5% vs. 20.9%, p<0.001). Functional recovery was higher in TPA-treated than in no-TPA cats (26.1% vs. 13.8%, p=0.007). Survival proportion was not different in TPA-treated and no-TPA (35.5% vs. 34.7%, p>0,05). Post-treatment creatinine and potassium were similar for TPA-treated and no-TPA (130 vs. 118 mmol/L, p=0.5 and 6.9 vs. 5.4 mmol/L, p=0.49, respectively).

Conclusion

Our study is the first to show an improvement in arterial recanalization and functional recovery with TPA in FATE without increasing mortality.

E-mail: cambournac@gmail.com