It is well known that certain cardiovascular abnormalities, frequently compress the airways in infants [1]. Two additional cardiac mechanisms of airway obstruction are described in this paper: progressive compression of the bronchial tree by left sided cardiac enlargement and infantile cardiac asthma due to compression of the small airways by pulmonary venous congestion. Functional and reversible collapse of the trachea is a frequent finding in cardiac asthma. Infants with these entities often appear to have primary pulmonary disease when in fact the underlying cause of their distress is cardiac in origin.