Based on prior knowledge, the feature STENOK_AN ("Exertional angina pectoris in the anamnesis") can provide information about the likelihood of chronic heart failure in the patient. Angina pectoris is a symptom of ischemic heart disease, which is a major cause of myocardial infarction. Therefore, the presence of exertional angina pectoris in the patient's medical history can be associated with a higher risk of myocardial infarction complications, including chronic heart failure.

Based on this information, the analysis of the relationship between the feature and the task can be done as follows:

- If the patient has reported "never" having exertional angina pectoris in the past, it is less likely for them to have chronic heart failure as a complication of myocardial infarction.
- If the patient has reported having exertional angina pectoris "during the last year" or "one year ago," it is more likely for them to have chronic heart failure as a complication of myocardial infarction.
- For other categories of STENOK_AN, such as "more than 5 years ago," "4-5 years ago," "two years ago," or "three years ago," it is difficult to make a precise prediction without further information. 

Based on this analysis, the dictionary can be created:

```json
{
	"no": ["never"],
	"yes": ["during the last year", "one year ago"]
}
```