This study investigated whether myocardial damage, as reflected by increased serum concentrations of cardiac-specific troponin I (cTnI), develops in dogs as a result of a bite from a common European viper (Vipera berus), and whether this damage occurs in the absence of clinically relevant ECG abnormalities. Twenty-four dogs presented following a snake bite were tested. On admission, and after 12, 24 and 36 hours, an ECG was recorded and serum was collected for analysis of cTnI from all the dogs. Thirteen dogs (54 per cent) had an undetectable serum cTnI concentration (<0.2 microg/l) and no abnormalities on ECG, five dogs (21 per cent) had increased serum concentrations of cTnI and no ECG abnormalities, six dogs (12.5 per cent) had increased cTnI concentrations and ECG abnormalities, and six dogs (12.5 per cent) had ECG abnormalities and undetectable cTnI concentrations. Only three dogs (12.5 per cent) had serum cTnI concentrations exceeding 1.0 microg/l at any time during the study. Evidence of myocardial cell damage was found in eight (32 per cent) of the 24 dogs. Cardiac arrhythmia was detected in three of these eight dogs.