This study was conducted at Oklahoma State University Center for Veterinary Health Sciences. Samples were collected from multiple private veterinary practices in Oklahoma and Texas.
Cardiotoxicity, Inflammation, and Immune Response after Rattlesnake Envenomation in the Horse
Article first published online: 1 NOV 2012
Copyright © 2012 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 26, Issue 6, pages 1457–1463, November/December 2012
How to Cite
Gilliam, L.L., Holbrook, T.C., Ownby, C.L., McFarlane, D., Sleeper, M.M., Martin, S., Levis, K. and Payton, M.E. (2012), Cardiotoxicity, Inflammation, and Immune Response after Rattlesnake Envenomation in the Horse. Journal of Veterinary Internal Medicine, 26: 1457–1463. doi: 10.1111/j.1939-1676.2012.01022.x
Portions of this data were presented at the 2011 ACVIM Forum in Denver, Colorado
- Issue published online: 20 NOV 2012
- Article first published online: 1 NOV 2012
- Manuscript Accepted: 6 SEP 2012
- Manuscript Revised: 19 JUN 2012
- Manuscript Received: 14 MAR 2012
- ACVIM Foundation
- Center for Veterinary Health Sciences, Oklahoma State University
- Snake bite;
- Troponin I
Cardiac abnormalities are reported in rattlesnake-bitten horses. The prevalence and cause are unknown.
To detect cardiac damage in rattlesnake-bitten horses by measuring cardiac troponin I (cTnI) and evaluating ECG recordings for presence of arrhythmias, and explore causes of this cardiac damage by measuring venom excretion, anti-venom antibodies, and tumor necrosis factor alpha (TNFα).
A total of 20 adult horses with a clinical diagnosis of rattlesnake bite and 6 healthy adult horses.
In a prospective clinical study, bite site swabs, blood samples, and urine samples were collected at various time points from 20 horses with a clinical diagnosis of snake bite. Continuous ECG recordings were obtained on the 20 affected horses and 6 normal control horses using 24-hour holter monitors. Plasma samples were assayed for cTnI, serum samples were assayed for TNFα and anti-venom antibodies, and bite site swabs and urine were assayed for venom.
Forty percent of rattlesnake-bitten horses (8/20) experienced myocardial damage (increased cTnI). Seventy percent (14/20) experienced a cardiac arrhythmia. There was a positive correlation between cTnI and TNFα (P < .02). Horses with cTnI ≥2 ng/mL were more likely to have antibody titers >5,000 (P < .05). No correlations were found between venom concentration and cTnI, anti-venom antibody titers, TNFα, or presence of arrhythmias.
Conclusions and Clinical Importance
Cardiac abnormalities in this population of horses indicate that cardiac damage after rattlesnake bite is common. Rattlesnake-bitten horses should be monitored for signs of cardiac damage and dysfunction. Long-term follow-up should be encouraged to detect delayed cardiac dysfunction.