Neonatal Nurse Practitioner Practice Exam

What heart sounds are indicative of aortic stenosis?

1. A harsh grade IV systolic murmur

2. A soft diastolic murmur

3. A ventriculo-atrial gallop

4. A continuous murmur

The correct answer is: A harsh grade IV systolic murmur

A harsh grade IV systolic murmur is indeed indicative of aortic stenosis. This type of murmur is typically associated with the turbulent blood flow that occurs when the left ventricle ejects blood through a narrowed aortic valve during systole. The intensity grading of murmurs ranges from I to VI, with grade IV being loud and readily audible, often accompanied by a palpable thrill. In aortic stenosis, the hearable characteristics of the murmur include its harsh quality, which arises from high-velocity blood flow through the constricted valve. The timing of this murmur is crucial; it occurs during the systolic phase of the cardiac cycle, correlating perfectly with the phase when the left ventricle is contracting and overcoming the increased resistance at the aortic valve. On the other hand, soft diastolic murmurs are more associated with other valvular heart issues, such as aortic regurgitation, while a ventriculo-atrial gallop typically relates to ventricular dysfunction and is not specific to aortic stenosis. Continuous murmurs are often characteristic of conditions like patent ductus arteriosus, not aortic stenosis. Therefore, the prototypical sound associated with aortic stenosis is