Based on my prior knowledge and analysis, I will analyze the relationship between the feature "ant_im" and the task of determining whether the patient shows chronic heart failure.

From the feature description, "ant_im" represents the presence of an anterior myocardial infarction (left ventricular) based on ECG changes in leads V1-V4. It is a categorical variable with the following categories: 
1. "QRS is like QS-complex"
2. "QRS has no changes"
3. "there is no infarct in this location"
4. "QRS is like QR-complex"
5. "QRS is like Qr-complex"

To determine the relationship between "ant_im" and chronic heart failure, we would need additional information about the patient's medical history, symptoms, and diagnostic test results. Without this information, it is not possible to directly infer the presence of chronic heart failure based on "ant_im" alone.

However, we can still provide a dictionary with the possible feature values for each target class:

```json
{
	"no": [
        "QRS is like QS-complex",
        "QRS has no changes",
        "there is no infarct in this location",
        "QRS is like QR-complex",
        "QRS is like Qr-complex"
    ],
	"yes": [
        "QRS is like QS-complex",
        "QRS has no changes",
        "there is no infarct in this location",
        "QRS is like QR-complex",
        "QRS is like Qr-complex"
    ]
}
```

Please note that without further information, we cannot determine the relationship between these feature values and the presence of chronic heart failure.