A 5-week-old infant born at 36 weeks' gestation is brought to the physician for a well-child examination. Her mother reports that she previously breastfed her for 15 minutes every 2 hours but now feeds her for 40 minutes every 4 hours. The infant has six wet diapers and two stools daily. At birth, she weighed 2675 g (5.9 Ibs) and was 47 cm (18.5 in) in length. She currently weighs 3085 g (6.8 lbs) and is 50 cm (19.7 in) in length. Vital signs are with normal limits. Cardiopulmonary examination shows a grade 4/6 continuous murmur heard best at the left infraclavicular area. Which of the following is the most likely diagnosis?

Question

A 5-week-old infant born at 36 weeks' gestation is brought to the physician for a well-child examination. Her mother reports that she previously breastfed her for 15 minutes every 2 hours but now feeds her for 40 minutes every 4 hours. The infant has six wet diapers and two stools daily. At birth, she weighed 2675 g (5.9 Ibs) and was 47 cm (18.5 in) in length. She currently weighs 3085 g (6.8 lbs) and is 50 cm (19.7 in) in length. Vital signs are with normal limits. Cardiopulmonary examination shows a grade 4/6 continuous murmur heard best at the left infraclavicular area.   Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

Eductional Objective: A patent ductus arteriosus (PDA) causes a continuous murmur best heard at the left infraclavicular or posterior interscapular region.  A small PDA is often asymptomatic and detected incidentally during routine cardiac auscultation.  It most commonly occurs in patients born prematurely and those with cyanotic congenital heart disease.

A 5-Week-Old Infant Born at 36 Weeks' Gestation Is Brought