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

Based on the given feature description, the feature MP_TP_POST represents paroxysms of atrial fibrillation at the time of admission to the intensive care unit or at a prehospital stage. 

Since the feature is categorical with two possible categories - "no" and "yes", we can include both categories in the dictionary for each target class.

For the target class "no" (indicating no chronic heart failure), the possible values of feature MP_TP_POST are "no" and "yes".

For the target class "yes" (indicating chronic heart failure), the possible values of feature MP_TP_POST are also "no" and "yes".

Note: It is not necessary to include all possible values of feature MP_TP_POST for each target class if there is uncertainty in predicting them.