A left-to-right shunt is suggested by the history of a murmur since early childhood, an abnormal X ray revealing cardiomegaly and an abnormal electrocardiogram, particularly in the absence of recent illness or significant cardiac symptoms or signs such as syncope and cyanosis.
Her relatively unremarkable presentation reflects the natural history of the lesion. Left-to-right shunts may be well tolerated for long periods of time before the onset of symptoms. Often, they are first detected in otherwise healthy adults with abnormal physical findings. Our patient's only symptom is palpitations, that may suggest an associated arrhythmia.