```json
{
	"no": ["no"],
	"yes": ["yes"]
}
```

In this case, the "n_p_ecg_p_10" feature has two possible values: "no" and "yes". Based on the given task, if the patient shows chronic heart failure, the target class is "yes", otherwise it is "no". The feature value "no" indicates the absence of complete LBBB on ECG at the time of admission to the hospital, while the value "yes" indicates its presence. Therefore, the possible values of the feature for the target class "no" is ["no"], and for the target class "yes" is ["yes"].