Based on my prior knowledge, I will analyze the relationship between the feature SVT_POST and the task of determining if the patient has chronic heart failure.

To analyze this, we can consider the following possibilities:

1. SVT_POST = 'no': If the patient does not have paroxysms of supraventricular tachycardia at the time of admission, it is less likely that they have chronic heart failure.
2. SVT_POST = 'yes': If the patient has paroxysms of supraventricular tachycardia at the time of admission, it may indicate chronic heart failure.

Now, let's create a dictionary with the possible values of feature SVT_POST for each target class:

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

Please note that the possible values for feature SVT_POST are only 'no' and 'yes'. Even though there might be other values for this feature, if they are hard to predict or not relevant to determining chronic heart failure, we do not need to include them in the dictionary.