Which heart characteristic may be present in a normal newborn heart assessment?

In a normal newborn heart assessment, a soft systolic murmur often indicates the presence of a left-to-right shunt, which can occur as a temporary phenomenon due to normal fetal circulation transitioning after birth. This type of murmur is typically benign and can be attributed to the still-developing cardiovascular system of the newborn. The ductus arteriosus, for instance, may still be patent and can create a small shunt, leading to the generation of a soft murmur during the systolic phase of the cardiac cycle.

In contrast, persistent loud diastolic sounds are not typical findings and could suggest pathological conditions requiring further investigation. An irregular heart rhythm in a newborn is often a cause for concern and may indicate underlying issues that need to be addressed. Additionally, absent blood flow would signify a critical problem, such as severe heart defect or cessation of circulation, which is not characteristic of a healthy newborn. Thus, the presence of a soft systolic murmur resulting from a left-to-right shunt aligns with normal variations typically observed in newborns.