Based on prior knowledge, it is not immediately apparent how the feature "n_r_ecg_p_03" (ventricular contractions on ECG at the time of admission to the hospital) is directly related to the task of determining whether the patient shows chronic heart failure. It is important to note that more domain-specific knowledge or analysis of the dataset itself would be needed to establish a relationship between this feature and the target variable.

However, regardless of the relationship, we can still create the dictionary as requested, including the possible values of the feature for each target class:

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

In this case, since the feature is categorical, it only has two possible values: "no" and "yes". Even though we don't have information on how these values relate to chronic heart failure, we can include them in the dictionary to fulfill the requirements.