```json
{
   "no": ["no"],
   "yes": ["yes"]
}
```
Based on the given feature description, the feature "n_p_ecg_p_11" has two categories: "no" and "yes". To determine if the patient shows chronic heart failure, we need to analyze the relationship between this feature and the target variable. Since the feature description does not provide any information about the relationship, we can assume that the presence of an incomplete right bundle branch block (RBBB) on the ECG at the time of admission could be an indication of chronic heart failure. Therefore, if the value of "n_p_ecg_p_11" is "yes", it suggests that the patient may have chronic heart failure. Conversely, if the value is "no", it suggests that the patient does not have chronic heart failure.