A 13-year-old Thoroughbred gelding was referred to the Texas Veterinary Medical Center, Texas A&M College of Veterinary Medicine and Biomedical Sciences, for echocardiographic evaluation. The horse had been hospitalized at the referring veterinarian's clinic for approximately 1 week for fever, tachycardia, limb edema, and lethargy Results of a CBC revealed marked leukocytosis (20,390 WBCs/μL; reference range, 5,400 to 14,300 WBCs/μL). Treatment included antimicrobials, glucocorticoids, and NSAIDs. The sudden onset of a loud right-sided heart murmur prompted referral for further evaluation. At the time of admission, the horse was quiet and alert and afebrile, with mild sinus tachycardia (heart rate,
Dr. Achen's present address is Michigan Veterinary Specialists, 1425 Michigan St NE, Ste F, Grand Rapids, MI 49503.