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

In this case, the feature "n_r_ecg_p_02" represents the presence or absence of frequent premature atrial contractions on an electrocardiogram (ECG) at the time of admission to the hospital. 

Based on the description, the feature has two categories: "no" and "yes". 

To determine if there is a relationship between this feature and the presence of chronic heart failure, we need to analyze how different values of the feature correspond to the target variable. 

By looking at the data, we can see that when the value of the feature is "no", it implies the absence of frequent premature atrial contractions on the ECG, and when the value is "yes", it implies the presence of such contractions.

To determine whether this feature indicates chronic heart failure, we need additional data or a model that considers the relationship between this feature and the target variable. However, based on the available information, we can conclude that the presence of frequent premature atrial contractions on the ECG at the time of admission to the hospital (value: "yes") may be an indication of chronic heart failure. Further analysis and modeling are needed to confirm this relationship.