Plasma taurine concentrations and M-mode echocardiographic measures in healthy cats and in cats with dilated cardiomyopathy

M‐mode echocardiography was completed and plasma taurine concentrations were determined in 79 healthy cats and 77 cats with dilated cardiomyopathy (DCM). In healthy cats, a relationship was not observed between plasma taurine concentrations and any M‐mode echocardiographic measurement. End‐systolic and end‐diastolic cardiac chamber dimensions were larger; wall thickness measures were smaller; and calculations of fractional shortening were less in cats with DCM than in healthy cats. Plasma taurine concentrations < 30 nmol/mL were detected in 7/79 healthy cats and in 52/77 cats with DCM. Of the 52 cats with DCM and an initial plasma taurine concentration < 30 nmol/mL, 23 died or were euthanized during the first post‐treatment week, 7 were lost to further study, and 22 improved after taurine supplementation. Of the 25 cats with DCM and an initial plasma taurine concentration > 30 nmol/mL, 9 died or were euthanatized during the first post‐treatment week, and 9 were lost to further study. Two cats did not improve, of which one died and one was euthanatized 4 to 8 weeks after initiation of taurine supplementation. Five cats with a plasma taurine concentration > 30 nmol/mL improved after taurine supplementation. Myocardial function subsequently deteriorated in three of these cats. Two of the three cats had signs of congestive heart failure redevelop.