A decrease attention span is not likely a result of regular activity. In fact, it would be the opposite way around.
Cardiac output is the term represent the rate measuring the amount of the blood that heart pumps out each time it beats.
Patients forget basic things on a day to day basis, making it hard for doctor's to keep track of what is working and what is not. Patients are often incredibly difficult to deal with, making their jobs harder than they already are.