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

Based on the given feature description and task, the feature "n_r_ecg_p_01" represents premature atrial contractions on the electrocardiogram (ECG) at the time of admission to the hospital. The feature is a categorical variable with two possible categories: "no" and "yes".

In order to determine if the patient shows chronic heart failure, we need to analyze the relationship between the feature and the target variable. However, without further information about the target variable or any data, it is not possible to infer the relationship or make predictions regarding chronic heart failure based solely on this feature.

Considering the given information, we can conclude that when the value of "n_r_ecg_p_01" is "no", it is possible that chronic heart failure is not present. When the value is "yes", it is possible that chronic heart failure is present. However, we cannot make any definitive statements without additional information or data.