Javma-journal of The American Veterinary Medical Association最新文献

Objective: To estimate the time until reliable echocardiography in healthy dogs by evaluating differences in measured echocardiographic variables in dogs before sedation, during sedation with dexmedetomidine, and after reversal with atipamezole.

Methods: 13 dogs were prospectively enrolled. Two-dimensional echocardiographic measurements on left atrial and ventricular dimensions and ventricular systolic function were obtained at each time point. Dogs underwent IV sedation with 10 µg/kg of dexmedetomidine and 0.2 mg/kg of butorphanol, and dexmedetomidine was reversed with atipamezole IM. Echocardiography was performed before sedation, during sedation, and 30 to 60 minutes, 2 hours, and 6 hours after reversal. Data were analyzed with a Bayesian multivariate hierarchical model.

Results: There were effects of sedation on the mean values of all echocardiographic variables. These effects varied among dogs, with most dogs expected to remain within normal reference ranges during and after sedation for all variables except ejection fraction and fractional shortening. The effects of sedation on ejection fraction and fractional shortening were widespread and persistent, such that 88% and 79% of dogs, respectively, were expected to measure outside the normal ranges during sedation. After reversal with atipamezole, this proportion declined, with approximately 9% of dogs estimated outside the normal reference ranges after 6 hours.

Conclusions: Effects of dexmedetomidine on echocardiographic measurements were detected 6 hours after reversal with atipamezole. Accurate cardiac assessment in dogs sedated with this drug is not likely to be possible on the same day as sedation.

Clinical relevance: Dogs sedated with this protocol and that have echocardiography performed within 6 hours following reversal should have results interpreted with caution.

Objective: To develop a machine learning (ML) model to identify fiducial points on canine ECGs to localize right-sided accessory pathways as posterior or anterior during ventricular preexcitation (VPE).

Methods: ECG recordings with VPE and documented accessory pathway locations were preprocessed for a 1-dimensional U-net algorithm. A web-based platform (https://setpsi.com/AccessoryPathways/) was created. Training used approximately 70% of pooled beats from 16 of 27 dogs. Testing used approximately 30% of pooled beats from 11 of 27 dogs to assess accurate diagnosis of posterior versus anterior accessory pathways. Vectorcardiograms and mean electrical axis (MEA) were calculated to validate the ML model. Fiducial boundary correctness and beat identification accuracy were assessed with receiver operator characteristic curves and reported as area under the curve (AUC; 95% CI). A Mann-Whitney test was used to compare MEA methods (median; IQR).

Results: The ML algorithm was trained on 3,405 beats and tested on 1,984 beats. The model identified fiducial points P wave to delta wave (AUC, 0.957; 95% CI, 0.957 to 0.958) and delta wave/QRS (AUC, 0.965; 95% CI, 0.964 to 0.966), classified individual beats as posterior (AUC, 0.917; 95% CI, 0.915 to 0.920) and anterior (AUC, 0.948; 95% CI, 0.947 to 0.949), and determined pathway location in 82% (9 of 11) of test dogs. Vectorcardiograms of posterior pathways showed oval or elliptical loops with superior leftward vectors, while anterior pathways displayed complex figure-eight loops with inferior leftward vectors. The MEA differed (P < .01) between posterior (-23.7°; IQR, 39.5°) and anterior (61.1°; IQR, 9.8°) pathways. Both methods validated the ML model.

Conclusions: The ML model accurately localized accessory pathways in canine VPE.

Clinical relevance: ML will advance the ability to accurately diagnose VPE.

Objective: Evaluate clinical and fecal parameters in dogs with refractory chronic enteropathy (CE) treated with repeated fecal microbiota transplantation (FMT) as adjunct treatment.

Methods: This was a prospective longitudinal observational study from September 25, 2021, to June 20, 2024. Thirty-nine dogs received 2 to 3 rectal FMTs over 1 month. Canine inflammatory bowel disease activity index (CIBDAI) and fecal samples were assessed for 6 months. Fecal samples were analyzed for dysbiosis index, bile acids, and calprotectin.

Results: 28 of 39 dogs responded to FMT. Eight dogs had a short-lasting response. Before FMT, baseline CIBDAI was equivalent in responders and nonresponders. Responders had a significantly decreased CIBDAI at 1 month, which remained unaltered at 6 months in long-lasting responders (LLRs). Baseline dysbiosis index (mean [95% CI]) was significantly lower in LLRs (-0.02 [-3.3 to 2.7]) versus nonresponders and short-lasting responders combined (N/SRs; 2.9 [-0.2 to 6.0]). Baseline percentage of secondary unconjugated fecal bile acids was higher in LLRs (65 [41 to 89]) versus N/SRs (30 [6 to 54]). Dysbiosis index decreased significantly at the time point for the third FMT in LLRs (-2.4 [-3.9 to 2.2]) but not in N/SRs (3.3 [-0.4 to 5.7]). Corticosteroid tapering was achieved in 13 responders. Mild adverse events were noted in 4 dogs.

Conclusions: This repeated FMT protocol was an effective adjunct treatment in refractory CE dogs, especially in dogs with no or mild dysbiosis. Marked dysbiosis and BA dysmetabolism before and after FMT appeared associated with no clinical response or a short-lasting response to FMT, potentially requiring repeated FMT.

Clinical relevance: Repeated FMT could reduce disease activity and corticosteroid usage in dogs with refractory CE.