heart murmur vs cardiac murmur

heart murmur and cardiac murmur both are nouns.

Word	Noun	Adjective	Verb	Adverb
heart murmur	Yes	No	No	No
cardiac murmur	Yes	No	No	No

As nouns, heart murmur and cardiac murmur are synonyms defined as:

heart murmur and cardiac murmur: an abnormal sound of the heart; sometimes a sign of abnormal function of the heart valves

Other synonyms of heart murmur include murmur.

heart murmur (noun)	cardiac murmur (noun)
an abnormal sound of the heart; sometimes a sign of abnormal function of the heart valves	an abnormal sound of the heart; sometimes a sign of abnormal function of the heart valves