Based on the given feature "n_p_ecg_p_12" (Complete RBBB on ECG at the time of admission to hospital) and the task of determining whether the patient has chronic heart failure, we can analyze the relationship between the feature and the target variable.

Since the feature is categorical with two possible categories, "no" and "yes," we will analyze the distribution of these categories for each class of the target variable (chronic heart failure).

Here is the dictionary representing the analysis:

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

Explanation:
- For the target class "no" (not having chronic heart failure), the only possible value for the feature "n_p_ecg_p_12" is "no."
- For the target class "yes" (having chronic heart failure), the only possible value for the feature "n_p_ecg_p_12" is "yes."

Note:
Since the values of "n_p_ecg_p_12" are categorical and the feature is specifically related to the target variable, there is no need to include any other values in the dictionary.