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

Based on the given feature description and task, it appears that the feature `n_p_ecg_p_04` represents the presence or absence of Type 1 Second-degree AV block (Mobitz I/Wenckebach) on ECG at the time of admission to the hospital. 

Since the target variable is whether the myocardial infarction complications data of the patient shows chronic heart failure, it seems that the presence or absence of the AV block could potentially be related to the occurrence of chronic heart failure.

The feature `n_p_ecg_p_04` has two possible categories: "no" and "yes". The dictionary represents the possible values of the feature for each target class. In this case, the values for the "no" class and "yes" class are simply the unique categories of the feature itself.