Lillycat, A friend's kitten was diagnosed with a grade 5 heart murmur and vet estimated a year to live. The cat lived until it was 15-1/2 yrs., so a heart murmur is not necessarily an early death sentence. Your cat is absolutely stunning and those green eyes are spectacular! I hope he has many many years ahead of him.
"We humans are indeed fortunate if we happen to be chosen to be owned by a cat." -- Anonymous