Based on prior knowledge, there is no direct relationship between gender (SEX) and the occurrence of chronic heart failure. Chronic heart failure can affect both males and females.

Taking into account that there is no specific relationship, the dictionary will contain all the possible values of SEX for both target classes (yes and no), even though the values of SEX may not be directly correlated with chronic heart failure.

Here is the dictionary:

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