Based on my prior knowledge and analysis of the relationship between the feature "np_04" (Third-degree AV block in the anamnesis) and the task of determining if the patient has chronic heart failure, we can create the following dictionary:

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

Since the feature "np_04" is a categorical variable with two categories, "no" and "yes," the dictionary indicates that if the value of "np_04" is "no," the patient does not show chronic heart failure, while if the value is "yes," the patient does show chronic heart failure.

Note: If there are additional values for "np_04" that are hard to predict, they can be excluded from the dictionary. However, in this case, since there are only two possible values, both categories are included in the dictionary.