Based on prior knowledge, the relationship between the feature GT_POST (Paroxysms of ventricular tachycardia at the time of admission to the intensive care unit) and the task of determining if the patient has chronic heart failure is uncertain. 

To create the dictionary, we need to analyze the values of GT_POST for each target class:

For the target class "no" (indicating no chronic heart failure), the possible values of GT_POST could be: ['no'].

For the target class "yes" (indicating chronic heart failure), the possible values of GT_POST could be: ['yes'].

Therefore, the dictionary would be as follows:

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

Please note that as the feature GT_POST is a categorical variable, the values can only be 'yes' or 'no'.