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

Based on the feature description, the feature FIB_G_POST represents whether the patient had ventricular fibrillation at the time of admission to the intensive care unit. To determine if the patient shows chronic heart failure, we need to analyze the relationship between this feature and the target variable.

In this case, the feature FIB_G_POST has two categories: "no" and "yes". To determine if it is related to chronic heart failure, we need to examine the occurrence of chronic heart failure in each category.

Since the target variable is not provided, it is not possible to determine the relationship between the feature FIB_G_POST and chronic heart failure accurately. Therefore, the dictionary includes the possible values for each category, but we do not have information about the relationship with the target class.