Hello Welcome to health care magic Dear patient ,it is a fact that the chronically diseased lung conditions like COPD(chronic obstructive lung disese seen in elderly smokers) can cause strain on heart especially on right side of the heart giving rise to right heart failure which is called cor pulmonale .In such patients findings will include RBBB, Right ventricular enlargement, high pulmonary artery pressures,tricuspid regurgitation, and clinically patient can have prominent neck veins, swelling over feet and abdomen, puffiness of face and pain in the right upper abdomen due to congestive hepatomegaly. How ever it is not know wheather recurrent attacks of CROUP can cause similar condition, theoretically it can be possible, or may be some other chronically lung damaging condition like cystic fibrosis, bronchiectasis or any other cobdition is causing it. It is also possible that the RBBB and right ventricular enlargement are not related to the lung condition but are primarly caused by the heart disease itself like ASD, mitral valve disease and may be even due to chronic pulmonary thromboembolism. so you consult a cardiologist and pulmonologist and get further evaluation of the child done by getting his HRCT chest and repeat ECHO done thanks Dr Arshad