Bacterial Endocarditis in Two Spanish Foals After Neonatal Septicemia

Equine neonatal septicemia could lead to the release of thrombus and heart valvular endocarditis. A relationship between activation of the renin-angiotensin-aldosterone-vasopressin (RAAV) axis and heart failure has been described in several species. This article describes the echocardiographic, electrocardiographic, and laboratory findings, including RAAV axis, in two Spanish foals with endocarditis after septicemia in comparison with two control groups matched by age and gender. Two Spanish foals (F1, 60-day-old colt; F2, 76-day-old filly) were presented with poor growth rate a month after being hospitalized because of septicemia. Colt F1 had hypercortisolemia and increased left ventricular internal dimensions in systole and diastole, increased left ventricular free wall thickness in diastole, interventricular septum thickness in diastole, and mitral valve thickness. Colt F1 also presented lower fractional shortening, ejection fraction, fractional wall thickness, and fractional septum thickness. Filly F2 showed hyperfibrinogenemia and increased values for aspartate aminotransferase, lactate dehydrogenase, creatin kinase, alkaline phosphatase, interventricular septum at systole, aorta diameter at the level of valve leaflets and sinotubular junction, and mitral and tricuspid valve thickness. The foals did not present systemic signs compatible with heart failure, heart arrhythmias were not found, and RAAV values were within the expected confidence limits. In conclusion, endocarditis without clinical signs of heart failure can appear shortly after septicemia in equine neonates. The measurement of the thickness of the valves by two-dimensional echocardiography is diagnostic. The lack of activation of RAAV in both foals might indicate that the severity of the heart problem was mild.