Based on my prior knowledge, frequent premature ventricular contractions on an electrocardiogram (ECG) can be associated with various cardiac conditions, including chronic heart failure. Therefore, it is likely that the presence of frequent premature ventricular contractions on an ECG (n_r_ecg_p_04) may be indicative of chronic heart failure.

To analyze the relationship between the feature n_r_ecg_p_04 and the presence of chronic heart failure, we need to examine the distribution of its values for both the "yes" and "no" classes of the target variable.

Since the target variable is whether the myocardial infarction complications data of this patient show chronic heart failure, let's assume the target variable is named "chronic_heart_failure" with binary values of "yes" or "no".

Here is the analysis:

- For the "no" class (No chronic heart failure):
  - Possible values of n_r_ecg_p_04 may include: ['yes', 'no'].

- For the "yes" class (Chronic heart failure):
  - Possible values of n_r_ecg_p_04 may include: ['yes', 'no'].

Based on this analysis, here is the dictionary with the possible values of feature n_r_ecg_p_04 for each target class:

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

Please note that the values of n_r_ecg_p_04 for both target classes are the same, which suggests that the feature alone may not be sufficient to accurately predict the presence of chronic heart failure. However, the presence of frequent premature ventricular contractions on an ECG can still provide some insight into the likelihood of chronic heart failure.