Myocardial contusion and rib fracture repair in an adult horse.

OBJECTIVE: To describe the clinical findings and management of myocardial injury secondary to blunt thoracic trauma and rib fracture in an adult horse.

CASE SUMMARY: A 6-year-old Warmblood gelding presented for treatment of blunt thoracic trauma. Sonographic examination of the thorax revealed a complete, mildly comminuted fracture of the left 5th rib with a fragment overlying the left atrium and coronary artery, hemothorax, and subjective left ventricular dyskinesis. Evidence of myocardial injury included atrial fibrillation, ventricular ectopy, and increased plasma cardiac troponin I concentration. The rib fracture was repaired under general anesthesia using a wire and plate technique. The atrial fibrillation converted to normal sinus rhythm coincidentally with intraoperative local infusion of mepivicaine in administration of intercostal perineural analgesia. Continuous, resting, and exercising electrocardiograms, serial cardiac troponin I concentrations and echocardiograms were used to monitor the myocardial injury. The horse was discharged after 5 days of hospitalization. Reexaminations 3 and 15 months after the initial trauma showed healing of the fracture and no evidence of myocardial sequelae.

NEW OR UNIQUE INFORMATION PROVIDED: To our knowledge, this is the first documentation of the diagnosis and monitoring of myocardial injury secondary to blunt thoracic trauma, as well as surgical repair of a rib fracture in an adult horse. Rib fractures and myocardial trauma can be successfully managed in adult horses and myocardial injury should be considered in cases of thoracic trauma.