Based on prior knowledge, there may be a relationship between the occurrence of paroxysms of supraventricular tachycardia (SVT_POST) at the time of admission to the intensive care unit and the presence of chronic heart failure in a patient with myocardial infarction complications. SVT_POST is a categorical variable with two possible categories: "no" and "yes".

To analyze the relationship between SVT_POST and chronic heart failure, we can examine the distribution of SVT_POST values for each target class (Yes or No for chronic heart failure). Based on this analysis, we can create a dictionary that summarizes the relationship.

Here is the generated dictionary:

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

In this case, since the task is to determine if the patient shows chronic heart failure, the "no" category of SVT_POST is associated with a negative outcome (absence of chronic heart failure). The "yes" category, on the other hand, includes both positive (presence of chronic heart failure) and negative outcomes.

Please note that SVT_POST with a value of "yes" may not always indicate chronic heart failure, as it could also occur in the absence of the condition.