Rubs, Gallops, and
You are listening to a
typical example of a murmur caused by a patent ductus arteriosis. This
vascular channel between the aorta and pulmonary artery remains open in a
small percentage of newborns, with a resultant left to right shunt. This
murmur is best heard over the upper left sternal edge, associated with a
thrill, and is characteristically continuous and machinery-like. If
untreated, the high flow through the pulmonary artery will eventually lead
to irreversible pulmonary hypertension with reversal of the shunt flow to
right to left (Eisenmenger syndrome). It should be differentiated from a
venous hum, a common innocent murmur often heard in children.
You may hear short breaks
in the otherwise continuous murmur, which is an artifact of looping the
sound by your computer.