How are innocent and pathologic systolic murmurs differentiated?

How are innocent and pathologic systolic murmurs differentiated?

Innocent murmurs are soft flow murmurs without physiologic consequences. Pathologic murmurs are loud, pansystolic, or late systolic and associated with a cardiac anomaly. The most common lesion associated with a sys-tolic murmur in the young infant is a ventricular septal defect or patent ductus arteriosus. This infant has signs of mild congestive heart failure (tachypnea and tachycardia) and should undergo a cardiology evaluation prior to sur-gery. Transthoracic echocardiography is presently the fastest, most accurate, and least invasive diagnostic tool to establish an exact anatomic diagnosis in the majority of patients with congenital heart disease.