Enlarged heart. Gross specimen of a heart that is enlarged (cardiomegaly). This is hypertrophy, when the enlargement is due to an increase in the size of the cells of the organ, rather than an increase in the number of cells. It can be a normal result of extensive exercise, or exertion of the heart as a result of obesity or extra strain on the heart for many different reasons. If heart function is normal, then general health should be maintained to prevent further problems. Cardiomegaly, if due to underlying problems, can develop into gradual failure of the heart (cardiomyopathy).