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

Analysis:
Based on my prior knowledge, atrial fibrillation (A-fib) is a common complication of chronic heart failure. A-fib is an irregular and often fast heart rate that occurs when the upper chambers of the heart (atria) experience chaotic electrical signals. Therefore, if the ECG rhythm at the time of admission to the hospital is atrial fibrillation (ritm_ecg_p_02 = 'yes'), it suggests that the patient may have chronic heart failure.

In the given feature description, the feature ritm_ecg_p_02 represents the ECG rhythm at the time of admission to the hospital, specifically categorizing it as atrial fibrillation ('yes') or not ('no'). Therefore, if the value of ritm_ecg_p_02 is 'yes', it indicates the presence of atrial fibrillation.

Since the target task is to determine if the patient shows chronic heart failure, the presence of atrial fibrillation (ritm_ecg_p_02 = 'yes') can be considered as an indication of chronic heart failure. Hence, if the target class is 'yes', the feature value can only be 'yes'. Similarly, if the target class is 'no', the feature value can only be 'no'.

Based on this analysis, the dictionary is generated with the possible values for each target class as follows:
- For the target class 'no', the only possible value for the feature ritm_ecg_p_02 is 'no'.
- For the target class 'yes', the only possible value for the feature ritm_ecg_p_02 is 'yes'.

Please note that the dictionary includes only the possible values of the feature for each target class, and the values are provided as strings in lists.