Cardiac troponin I levels in canine pyometra

Abstract

Background: Myocardial injury may contribute to unexpected deaths due to pyometra. To detect myocardial damage, measurement of cardiac troponin 1 (cTnl) is currently the most sensitive and specific method. The aims of the present study were to evaluate presence of myocardial damage in canine pyometra by analysis of cTnl, to explore whether myocardial injury was associated with systemic inflammatory response syndrome (SIRS) and to evaluate whether other clinical or laboratory parameters were associated with cTnl increase. Methods: Preoperative plasma levels of cTnl were investigated in 58 female dogs with pyometra and 9 controls. The value of physical examination findings, haematological, serum biochemical and pro-inflammatory (CRP and TNF-α) parameters as possible predictors of increased cTnl levels was also evaluated. Results: Seven dogs with pyometra (12%) and one control dog (11%) had increased levels of cTnl. In the pyometra group, the levels ranged between 0.3-0.9 μg l-1 and in the control dog the level was 0.3 μg l-1. The cTnl levels did not differ significantly between the two groups. No cardiac abnormalities were evident on preoperative physical examinations. Four of the pyometra patients died within two weeks of surgery, of which two were examined post mortem. In one of these cases (later diagnosed with myocarditis and disseminated bacterial infection) the cTnl levels increased from 0.9 μg l-1 preoperatively to 180 μg l-1 the following day when also heart arrhythmia was also detected. The other patient had cTnl levels of 0.7 μg l-1 with no detectable heart pathology post mortem. CTnl increase was not associated with presence of SIRS. There was a trend for the association of cTnl increase with increased mortality. No preoperative physical examination findings and few but unspecific laboratory parameters were associated with increased cTnl levels. Conclusion: Increased cTnl levels were observed in 12% of the dogs with pyometra. The proportions of dogs with cTnl increase did not differ significantly in the pyometra group compared with the control group. CTnl increase was not associated with presence of SIRS. A trend for association of cTnl increase and mortality was observed. Preoperative physical examination findings and included laboratory parameters were poor predictors of increased cTnl levels.