Based on my prior knowledge, the feature "n_r_ecg_p_08" represents the presence or absence of paroxysms of supraventricular tachycardia on the electrocardiogram (ECG) at the time of admission to the hospital. To determine the relationship between this feature and the target variable of chronic heart failure, we need to analyze the values of "n_r_ecg_p_08" for each target class.

To create the dictionary, we will go through the given dataset and identify the values of "n_r_ecg_p_08" for patients who do and do not have chronic heart failure. 

Let's assume we have a dataset that contains the following information:

|  n_r_ecg_p_08 | Chronic Heart Failure |
|--------------|----------------------|
|    no        |         no           |
|    no        |         yes          |
|    yes       |         no           |
|    yes       |         yes          |

Based on this dataset, we can analyze the relationship and create the dictionary:

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

In the dataset, for patients without chronic heart failure, the possible values for "n_r_ecg_p_08" are "no". For patients with chronic heart failure, the possible values for "n_r_ecg_p_08" are "no" and "yes".