An 8-month-old with patent ductus arteriosus arrives for a follow-up. Which finding should the nurse document in the medical record?

• A. Machinery murmur
• B. Systolic click
• C. Harsh holosystolic murmur
• D. Fixed split S2

Answer: (A)

A patent ductus arteriosus causes a continuous left-to-right shunt from the aorta into the pulmonary artery, which produces a characteristic continuous “machinery-like” murmur heard best at the left upper sternal border. This murmur spans both systole and diastole, reflecting the ongoing flow through the PDA throughout the cardiac cycle. In an 8-month-old, this finding remains a hallmark when the ductus hasn’t closed, and it may be accompanied by signs like bounding pulses and a wide pulse pressure due to runoff into the pulmonary circulation.

A systolic click points to mitral valve prolapse, a harsh holosystolic murmur suggests conditions such as a ventricular septal defect, and a fixed split S2 is typical of an atrial septal defect. These patterns do not match the continuous machinery murmur of a PDA, so the documented finding most consistent with PDA is the continuous, machinery-like murmur.