Based on my prior knowledge, I can analyze the relationship between the feature "STENOK_AN" and the task of determining whether the patient shows chronic heart failure.

Since "STENOK_AN" represents the presence or absence of exertional angina pectoris in the patient's medical history, it can provide insights into the possibility of chronic heart failure. Exertional angina pectoris, recurrent chest pain or discomfort during physical activity, is often associated with coronary artery disease, which can lead to heart failure.

To analyze the relationship, I would consider the following:

1. Patients who have never experienced exertional angina pectoris ("never" category) are less likely to have chronic heart failure.
2. Patients who have experienced exertional angina pectoris within the last year ("during the last year" category) are more likely to have chronic heart failure.
3. Patients who have experienced exertional angina pectoris more than 5 years ago ("more than 5 years ago" category) may or may not have chronic heart failure, as their condition could have improved or worsened over time.
4. Patients who have experienced exertional angina pectoris between 4-5 years ago ("4-5 years ago" category) may or may not have chronic heart failure, as their condition could have improved or worsened over time.
5. Patients who have experienced exertional angina pectoris one or two years ago ("one year ago" or "two years ago" category) are more likely to have chronic heart failure.
6. Patients who have experienced exertional angina pectoris three years ago ("three years ago" category) may or may not have chronic heart failure, as their condition could have improved or worsened over time.

Based on this analysis, I will now create the dictionary with the values for the target classes "no" and "yes":

```json
{
	"no": ["never", "more than 5 years ago", "4-5 years ago", "three years ago"],
	"yes": ["during the last year", "one year ago", "two years ago"]
}
```

Please note that the above information is an analysis based on general knowledge and assumptions. It is important to consult medical professionals or refer to specific research studies for accurate and precise conclusions.