Based on prior knowledge, it is possible that patients with chronic heart failure may have a higher likelihood of experiencing paroxysms of ventricular tachycardia at the time of admission to the intensive care unit (ICU).

To analyze the relationship between the feature "GT_POST" and the presence of chronic heart failure, we can examine the values of "GT_POST" for patients with and without chronic heart failure. Based on this analysis, we can create a dictionary as requested.

Here is a possible dictionary for the feature "GT_POST" in relation to the presence of chronic heart failure:

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

This dictionary suggests that the feature "GT_POST" has a direct relationship with the presence of chronic heart failure. Patients with chronic heart failure tend to have the value "yes" for "GT_POST," while patients without chronic heart failure usually have the value "no" for "GT_POST."