Evidence of myocardial injury in horses with colic

Abstract

Development of endotoxemia associated with gastrointestinal injury is often observed in horses with colic. Such patients are likely to develop cardiovascular complications associated with endotoxemia, including myocardial injury. Few studies have investigated the prevalence of myocardial injury in horses with colic. Cardiac biomarkers such as cardiac troponin I (cTnI) have been extensively used in human and veterinary medicine for diagnosis of myocardial injury. The aim of the present study was to investigate the occurrence of myocardial injury in horses with colic by measuring serum cTnI concentrations. Myocardial tissue samples from non-surviving horses were also subjected to histopathological evaluation. Serum cTnI concentration was measured in 10 healthy horses and 39 horses with colic. Associations were determined of cTnI concentration, and variables such as health status (healthy and horses with colic), type of colic (inflammatory, impaction, and unknown), the severity of abdominal pain (mild, moderate and severe), and clinical outcome (survivor to discharge and non-survivor). As compared with healthy horses, cTnI concentrations were significantly elevated in horses with colic (P = 0.004). In horses with colic, an abnormal cTnI concentration was significantly associated with inflammatory colic (P<0.05), severe abdominal pain (P<0.01), and negative clinical outcome (P<0.0001). Further, histopathological evaluation of the myocardial muscles revealed a varying degree of myocardial degeneration and necrosis. The present study suggested that horses with severe colic and increased cTnI levels are more likely to develop myocardial injury. Elevated levels of cTnI may also be indicative of poor prognosis in horses with severe colic.