Yes but. First, let me say that if you have heart failure and are short of breath you should see your physician today. There are many causes of worsening symptoms in heart failure, from taking too much fluid or salt in to worsening of your underlaying disease (for you this sounds like atherosclerosis). A recent history, physical plus labs would help determine where to focus diagnostic or treatment effort.
Maybe. Could be that your coronary artery disease has worsened and you are having ischemia (lack of oxygen) to the heart. Or it could be that your symptoms are progressing due to the gradual weakening of the contractility (strength of the heart muscle) of the heart. This occurs in heart failure even without having more blockages. You could also have too much fluid due to diet or medication imbalances.