For many males, though, it is much more. ED, as it is formally known, is often an early warning sign of heart disease or other circulatory problems. The vessels in the penis are similar in size to the coronary arteries. For this reason, if someone develops erectile dysfunction we start to suspect that they have atherosclerotic plaques in their hearts. So yes, it is a good sign that you are not experiencing ED, but it doesn't mean for 100% certain that your heart is in good shape.