Based on my prior knowledge, the slope of the peak exercise ST segment (ST_Slope) can provide some insights into the presence of heart disease. Here is the analysis of the relationship between the feature and the target:

- Up: An upward-sloping ST segment during exercise is considered abnormal and might indicate the presence of heart disease.
- Flat: A flat ST segment during exercise is less common in individuals without heart disease, but it does not strongly correlate with the presence of heart disease.
- Down: A downward-sloping ST segment during exercise is associated with a lower risk of heart disease.

Based on this analysis, let's create the dictionary:

```json
{
	"no": ["Flat"],
	"yes": ["Up", "Down"]
}
```
Note that the values "Flat" are included in the "no" list because they are less common in individuals without heart disease. The values "Up" and "Down" are included in the "yes" list as they indicate an abnormal ST segment and are more likely to be associated with heart disease.