Based on prior knowledge, the presence or history of arrhythmia in the anamnesis can be associated with a higher risk of chronic heart failure. Therefore, it is possible that patients with a positive history of arrhythmia (nr_11 = 'yes') may show chronic heart failure, while patients without a history of arrhythmia (nr_11 = 'no') may not necessarily have chronic heart failure.

Based on this analysis, here is the requested dictionary:

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

Please note that the dictionary includes all possible values of feature nr_11 for each target class, including cases where there are no other values.