Based on prior knowledge, the presence of ventricular fibrillation at the time of admission to the intensive care unit (FIB_G_POST) can be a potential risk factor for chronic heart failure in patients with myocardial infarction complications. To analyze the relationship between FIB_G_POST and the presence of chronic heart failure, we can examine the FIB_G_POST values for each target class.

Let's create the dictionary:

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

In this case, since the feature FIB_G_POST only has two distinct categories: 'no' and 'yes', we can include all values in the dictionary.