X-ray Chest
It is helpful in assessing heart size. One should look for presence of pericarditis, pulmonary oedema or pulmonary congestion.
ECG
One should look for prolonged PR interval which is indicative of carditis. Also look for evidence of myocarditis in form of sinus tachycardia, QRST changes and AV block.
Echocardiography
It is very useful in diagnosis of carditis and rheumatic valvular heart disease. It can identify valvular regurgitation not picked clinically. It is useful to assess progress of rheumatic heart disease by serial echocardiography.