Based on prior knowledge, LBBB (Left Bundle Branch Block) on an ECG (Electrocardiogram) can be an indicator of heart disease. LBBB is a conduction abnormality in which the electrical signal that controls the contraction of the left ventricle of the heart is delayed or blocked.

To analyze the relationship between the feature "n_p_ecg_p_07" (LBBB on ECG at the time of admission to the hospital) and the task of determining chronic heart failure, we can examine the distribution of the feature values for each target class.

Here is a possible dictionary based on this analysis:

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

Since the feature "n_p_ecg_p_07" only has two categories, namely "no" and "yes," we include all possible values for each target class. In this case, the value "no" represents the absence of LBBB on ECG, and the value "yes" represents the presence of LBBB on ECG.

Note that for the kind of values that are hard to predict, we can exclude them from the dictionary. However, as there are only two possible values for this feature, it is sufficient to include both "no" and "yes" in the dictionary.