The study was completed at the University of California, Davis. There was no financial backing provided for this research. The results have not been presented at any meeting.
Congenital Cardiac Defects in Neonatal Foals: 18 Cases (1992–2007)
Article first published online: 4 JAN 2010
Copyright © 2010 by the American College of Veterinary Internal Medicine
Journal of Veterinary Internal Medicine
Volume 24, Issue 1, pages 206–212, January/February 2010
How to Cite
Hall, T.L., Magdesian, K.G. and Kittleson, M.D. (2010), Congenital Cardiac Defects in Neonatal Foals: 18 Cases (1992–2007). Journal of Veterinary Internal Medicine, 24: 206–212. doi: 10.1111/j.1939-1676.2009.0445.x
- Issue published online: 4 JAN 2010
- Article first published online: 4 JAN 2010
- Submitted July 15, 2009; Revised September 27, 2009; Accepted October 21, 2009.
Background: Literature available regarding congenital cardiac defects in foals is limited to reports of individual cases or small case series.
Objective: To describe the clinical, echocardiographic, and necropsy findings and breed predilection of congenital cardiac defects in neonatal foals.
Animals: Eighteen foals <15 days of age with 1 or more congenital cardiac defects.
Methods: Medical records of foals diagnosed with congenital cardiac defects at the William R. Pritchard Veterinary Medical Teaching Hospital were reviewed. Data collected included history, signalment, clinical signs, laboratory data, diagnostic and necropsy results, and outcome.
Results: Arabian foals represented 39% of cases with congenital cardiac defects and were significantly (P= .004) overrepresented (OR = 4.7 [CI: 1.8–12.4]) compared with the general hospital population. Ventricular septal defect (VSD) (14/18), tetralogy of Fallot (5/18), and tricuspid valve atresia (4/18) were the most common defects identified. A ≥3/6 heart murmur (14/14) accompanied by tachycardia (14/17), tachypnea (17/17), and cyanosis of mucous membranes (7/16) were the most common clinical signs. Concurrent congenital defects were common (9/18). Two foals, both with VSD, survived for ≥ 8 years after diagnosis and 1 was a successful performance horse.
Conclusions and Clinical Relevance: Arabian horses appear to have a predisposition for cardiac defects. The presence of a loud murmur (≥ 3/6), cyanotic membranes, and tachycardia or tachypnea in a neonatal foal should warrant thorough evaluation of the heart for congenital defects. Foals with cardiac defects should be closely evaluated for concurrent congenital defects in other body systems.