Based on my analysis of the relationship between the feature endocr_03, which represents the presence of Thyrotoxicosis in the patient's medical history, and the task of determining whether the patient has chronic heart failure, I can generate the following dictionary:

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

Explanation:
- In this case, the value of the feature endocr_03 is either "no" or "yes". 
- For patients without chronic heart failure (target class "no"), the only possible value for endocr_03 is "no". 
- For patients with chronic heart failure (target class "yes"), the only possible value for endocr_03 is "yes". 

Since the possible values for endocr_03 are specific and there are no other potential values, both lists in the dictionary contain only one string value.