 After successful treatment, the patient is monitored for the rest of their life by a specialist to ensure that problems do not occur.Failure to treat the condition yields a mortality rate of 90% at a median age of 4 days.Death occurs due to increased blood flow from the left side of the heart (oxygenated blood) to the right side (deoxygenated blood), inducing heart failure; pulmonary edema; and eventual closing of the ductus arteriosus.