A. Chest X-ray
The chest x-ray shows a dilated heart that increases to severe proportions as the disease progresses. The lungs may show evidence of fluid accumulation with pleural effusions, but the lung fields may be relatively clear if mainly right heart failure occurs.
B. Blood Tests
In Chagas disease the serum aldolase is usually elevated. A complement fixation test (Machado-Guerreiro test) that has high specificity and sensitivity is used to identify chronic Chagas disease. Xenodiagnosis is the preferred test in endemic areas. With this test reduviid bugs bred in the laboratory are allowed to bite the patient. The parasites are then found in the intestine of the insect proving infection in the patient.
C. Echocardiography
Echocardiography shows enlargement of all four heart chambers in Chagas patients. There is also a reduction in the ejection fraction. On echo, the appearance of Chagas is distinctive: there is hypokinesis, poor contractility of the left ventricular posterior wall, relatively preserved intra-ventricular septal wall motion, and poor movement of the apical segment of the heart with dilatation and aneurysmal formation.