Complex sentence: A functional murmur or "physiologic murmur," is a heart murmur that is primarily due to physiologic conditions outside the heart, as opposed to structural defects in the heart itself.
Split into simpler sentences: A functional murmur or "physiologic murmur," is a heart murmur that is primarily due to physiologic conditions outside the heart. Other types of murmurs are due to structural defects in the heart itself.