Right ventricular hypertrophy is the most common cardiovascular change seen on the chest x-ray of the patient with pulmonary artery hypertension. This is caused by the need for increased force to pump against the increased pressure in the pulmonary arteries. Other cardiac changes may occur over time, such as hypertrophy of the left atrium, right atrium, and left ventricle, but the most likely change is right ventricular hypertrophy.