During winter outbreaks of respiratory syncytial virus bronchiolitis from 2002 to 2004, three infants presented with a presumptive diagnosis of lower respiratory tract infection and wheezing. The clinical condition in two cases was rapidly progressive and precipitated into intractable shock; clinical and instrumental examinations revealed a cardiac origin of their illness. A subacute presentation permitted a cardiological assessment and a proper treatment in the third infant. An abnormal origin of the left coronary artery from the pulmonary trunk was demonstrated in all cases. The concurrent acute airway infection had a catastrophic effect on the underlying cardiovascular anomaly leading to refractory cardiogenic shock and death.
Conclusion: Admission chest X-ray film and arterial gas analysis can raise the suspicion of cardiac involvement when treating a severe wheezing episode in young infants. Paediatric cardiological evaluation with two-dimensional echocardiography may eventually reveal this rare condition, whereas cardiac catheterisation with aortography remains the standard means of diagnosis.