Background: Concentrations of cardiac troponin I (cTnI) and C-reactive protein (CRP) might be associated with cardiac remodeling in dogs with myxomatous mitral valve disease (MMVD). Age- and sex-dependent variations in cTnI concentration have been described.
Objective: To investigate whether plasma concentrations of cTnI and CRP are associated with severity of MMVD, and investigate potential associations of dog characteristics on cTnI and CRP concentrations.
Animals: Eighty-one client-owned dogs with MMVD of varying severity.
Methods: Dogs were prospectively recruited for the study. Dogs were classified according to severity of MMVD. Plasma cTnI was analyzed by a high sensitivity cTnI assay with a lower limit of detection of 0.001 ng/mL, and plasma CRP was analyzed by a canine-specific CRP ELISA.
Results: Higher cTnI concentrations were detected in dogs with moderate (0.014 [interquartile range 0.008–0.029] ng/mL, P= .0011) and severe (0.043 [0.031–0.087] ng/mL, P < .0001) MMVD, compared with healthy dogs (0.001 [0.001–0.004] ng/mL). Dogs with severe MMVD also had higher cTnI concentrations than dogs with mild (0.003 [0.001–0.024] ng/mL, P < .0001) and moderate (P= .0019) MMVD. There were significant associations of age, CRP, heart rate, and left ventricular end-diastolic diameter, on cTnI concentration C-reactive protein did not differ among severity groups, but was significantly associated with cTnI, breed, and systolic blood pressure on CRP concentration.
Conclusions and Clinical Importance: Analysis of cTnI concentration has potential to increase knowledge of overall cardiac remodeling in dogs with MMVD. However, effect of age on cTnI needs consideration when assessing cTnI.