James had been complaining of difficulty breathing. His doctor diagnosed an increase in the size of his heart. What is James suffering from?

Cardiomegaly

Explanation: An enlarged heart, which is usually a sign of another condition.

Cardiomegaly is usually a sign of another condition such as a heart valve problem or heart disease. It may also signal a prior heart attack. It can also occur from bodily stress caused by pregnancy or certain infections.

Symptoms, if any, may include shortness of breath and swelling (edema).

The underlying condition needs treatment. This may include medications, medical procedures, or surgery in rare cases.

Cardiomegaly is usually a sign of another condition such as a heart valve problem or heart disease. It may also signal a prior heart attack. It can also occur from bodily stress caused by pregnancy or certain infections.

the answer to your question is (pancreas).