Based on prior knowledge, it is difficult to determine the relationship between the feature "ASP_S_n" and the task of identifying chronic heart failure. Acetylsalicylic acid (ASA) is commonly prescribed to prevent blood clots in patients at risk for heart attack or stroke, but it may not be directly linked to chronic heart failure.

To create the dictionary, we can assume that there is no specific relationship between "ASP_S_n" and chronic heart failure and include all possible values of "ASP_S_n" for both target classes. Hence, the dictionary will contain all the categories of "ASP_S_n" for both "yes" and "no" classes.

Here is the dictionary in Markdown format:

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

Please note that the values in the dictionary are presented as strings in lists, as specified in the format.