Duffy is 13 now - diagnosed with a murmur when he was 5. He had an ultrasound then, the murmur was an "innocent" murmur. When he went to the Vet, he got in a twit and the murmur was noticeable. No meds needed.

Last year, he had another ultrasound as the Vet thought the murmur was louder, and supposedly innocent murmurs don't change. Same Cardiologist did the test. Results - the same. No meds needed.

If it were my cat, I would opt for the ultrasound - that will be definitive.