Based on prior knowledge, there may be a relationship between obesity in the patient's medical history (endocr_02 feature) and the presence of chronic heart failure as a complication of myocardial infarction (target variable). 

To analyze the relationship, we'll examine the distribution of endocr_02 values for each target class (yes: chronic heart failure, no: no chronic heart failure). Based on this analysis, we'll create a dictionary with the possible values of endocr_02 for each target class.

Here's the analysis and the resulting dictionary:

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

Explanation:

- The "no" class represents cases where the patient does not have chronic heart failure as a complication. From the available feature values, there is only one possible value: "no". Therefore, the list of values for the "no" class will be ["no"].

- The "yes" class represents cases where the patient does have chronic heart failure as a complication. The available feature values are "no" and "yes". Hence, the list of values for the "yes" class will be ["no", "yes"].

Note: As requested, we only included the possible values in the dictionary.