Double‐outlet right ventricle in a 10‐month‐old Friesian filly

Abstract

A 10-month-old Friesian filly had a presentation that was consistent with chronic left- and right-sided congestive heart failure. Clinical pathology findings included abnormal haematological and biochemical variables, abnormal blood gas values and increased serum concentration of cardiac troponin I. Echocardiography revealed cardiac chamber dilation and dextropositioning of the aorta. Radiography revealed a generally enlarged heart and pulmonary interstitial infiltration. These findings were supported at necropsy and the diagnosis of double-outlet right ventricle was confirmed. The pathological changes and physiological responses subsequent to double-outlet right ventricle have not previously been described in detail in horses. Clinical progression closely resembles that seen in humans, in whom antemortem diagnosis relies on echocardiography. In horses, complex cardiac disease presents a diagnostic challenge to the clinician. Appropriate therapy must be based on an accurate diagnosis.

Serum cardiac troponin I concentrations in horses with cardiac disease

“…Serum concentrations of cTn can be elevated in horses with ventricular tachyarrhythmias, monensin toxicosis and atypical myopathy . Elevations also occur in horses with atrial fibrillation, structural heart disease and amyloidosis …”

Troponin assays in the assessment of the equine myocardium

“…Although all currently available commercial troponin I assays were designed for human patients, there are numerous reports of their use in horses with cardiac disease. Published studies have found increases in troponin I levels above presumed reference levels in horses with piroplasmosis, atypical myopathy, ruptured aortic jet lesions, structural cardiac disease and neoplasia, as well as after transvenous electrical cardioversion [1,7,[59][60][61][62]. Serum levels of cTnI showed a statistically significant increase after i.v.…”

IN THIS ISSUE – May 2009

“…A case report of a filly describes pathological changes and physiological responses subsequent to double‐outlet right ventricle that have not previously been described in detail in horses 7 …”