Based on prior knowledge, we can analyze the relationship between the feature "GEPAR_S_n" and the presence of chronic heart failure in myocardial infarction complications data.

In this case, we can expect that patients who use anticoagulants in the ICU (GEPAR_S_n = 'yes') are less likely to have chronic heart failure compared to patients who do not use anticoagulants (GEPAR_S_n = 'no'). Anticoagulants are often prescribed to reduce the risk of blood clot formation, which is one of the causes of chronic heart failure.

Based on the analysis, the possible values of feature GEPAR_S_n for the target class "no" (patients without chronic heart failure) would be ['yes', 'no'], as both group of patients can have an indication to use or not to use anticoagulants. Similarly, the possible values of feature GEPAR_S_n for the target class "yes" (patients with chronic heart failure) would also be ['yes', 'no'].

Therefore, the dictionary representing the relationship between the feature and the target is as follows:

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