Cardiac troponin T as an indicator of reduced left ventricular contractility in experimental anthracycline-induced cardiomyopathy.

PURPOSE: Cardiac troponin T (cTnT) plasma concentration is considered a useful marker of anthracycline-induced cardiomyopathy. In this study we used daunorubicin-treated Chinchilla rabbits as a model to investigate the relationship between left ventricular contractility and cTnT plasma concentrations. METHODS: Two groups of animals were used: a control group (n=8) received i.v. saline, and an experimental group (n=11) received daunorubicin (3 mg/kg, i.v.). The substances were administered once weekly for 10 weeks, and 5-7 days after the last administration, left ventricular cardiac contractility (dP/dtmax) was invasively measured as a contractility index and blood was sampled for cTnT concentration determination (Elecsys Troponin T STAT immunoassay). RESULTS: Cardiac contractility was significantly lower in seven surviving daunorubicin-treated animals than in control animals (745.7+/-69.3 vs 1393.4+/-25.5 kPa/s; P<0.001), while cTnT plasma concentrations were significantly increased (medians 0.278 vs 0.000 ng/ml; P<0.001). When the dP/dtmax values of individual daunorubicin-treated animals were plotted against the corresponding cTnT plasma concentrations, a close negative linear correlation was found (R=-0.910; P<0.005; regression equation: dP/dtmax=-1861*cTnT+1234). CONCLUSIONS: This study suggests that determination of cTnT plasma levels, which is simple and inexpensive, could be used in anthracycline-treated patients for left ventricular systolic function assessment and contractility estimation.