A 6-day-old boy is brought to the office for a routine visit after birth. The patient is exclusively breastfed with adequate voiding and stooling. Prenatal and birth histories are unremarkable. He was born full term via spontaneous vaginal delivery. Temperature is 37.2 C (99 F), blood pressure is 82/52 mm Hg, pulse is 144/min, and respirations are 42/min. Oxygen saturation is 98% on room air. The patient is comfortable and in no distress. Lungs are clear to auscultation. A soft, 2/6 holosystolic murmur is heard at the left lower sternal border. Apical cardiac impulse is normal. Brachial and femoral pulses are 2+ and equal. The skin is pink and well perfused. Which of the following is the most appropriate next step in management of this patient?

Question

A 6-day-old boy is brought to the office for a routine visit after birth.  The patient is exclusively breastfed with adequate voiding and stooling.  Prenatal and birth histories are unremarkable.  He was born full term via spontaneous vaginal delivery.  Temperature is 37.2 C (99 F), blood pressure is 82/52 mm Hg, pulse is 144/min, and respirations are 42/min.  Oxygen saturation is 98% on room air.  The patient is comfortable and in no distress.  Lungs are clear to auscultation.  A soft, 2/6 holosystolic murmur is heard at the left lower sternal border.  Apical cardiac impulse is normal.  Brachial and femoral pulses are 2+ and equal.  The skin is pink and well perfused.  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

Explanation: 11ec25c8_d63d_48c3_bc81_55995939d48e_MD0003_00 This patient with a soft murmur is asymptomatic and has normal vital signs and extracardiac findings. However, the holosystolic timing of the murmur is a pathologic feature that warrants further evaluation. In this case, the patient most likely has a ventricular septal defect (VSD). ventricular septal defect (VSD) After birth, VSD serves as a left-to-right shunt due to declining pulmonary vascular resistance (PVR) and rising systemic vascular resistance. Small VSDs typically shunt a hemodynamically insignificant volume of blood and are often loud in intensity due to turbulent flow. Moderate to large VSDs lead to right ventricular volume overload and pulmonary overcirculation. This patient's soft (ie, quiet), 2/6 murmur at the lower left sternal border suggests relatively low-turbulence blood flow across a large (rather than a small) defect. As PVR declines, shunt volume increases and can lead to signs of high-output heart failure (eg, respiratory distress, poor weight gain) due to the inability of the left ventricle to keep up with increased pulmonary venous return. Echocardiography should be performed to evaluate the size of the VSD (and therefore the risk of progression to heart failure) and assess for other underlying defects (eg, tetralogy of Fallot). In addition to holosystolic timing, features that suggest a pathologic murmur and warrant echocardiography include loud intensity, harsh quality, and diastolic timing. (Choice A) Indomethacin, which inhibits cyclooxygenase and prostaglandin, can be used to promote closure of a symptomatic patent ductus arteriosus (DA). Unlike in this patient, the murmur of a patent DA is continuous and machine-like and located along the left upper sternal border or infraclavicular area. (Choices B and C) Prostaglandin E1 maintains the patency of the DA in infants with ductal-dependent congenital heart defects (eg, transposition of the great arteries). Arterial blood gas shows low PO₂ due to mixing of deoxygenated and oxygenated blood. Patients develop cyanosis on DA closure, usually by day 2 or 3 of life. ₂ (Choice E) Asymptomatic murmurs with only benign features (eg, grade 1-2, soft/vibratory, early-peaking systolic) are common in childhood and often require only reassurance. Although this patient's murmur is soft, the holosystolic timing is a feature of pathologic murmurs and requires further evaluation. Educational objective: Pathologic murmurs are typically loud in intensity, harsh, or holosystolic or diastolic. Ventricular septal defect classically causes a holosystolic murmur at the left lower sternal border and warrants evaluation with echocardiography to determine the size and risk of progression to heart failure. References: Prevalence and clinical significance of cardiac murmurs in schoolchildren. (http://www.ncbi.nlm.nih.gov/pubmed/26070974) Ventricular septal defect. (http://www.ncbi.nlm.nih.gov/pubmed/29261884)

A 6-Day-Old Boy Is Brought to the Office for a Routine