Bengal Cat with heart Murmur

[Lillycat]

Hello So My husband and I "adopted" an unpapered Bengal a couple weeks ago and know nothing about her medical history. She is supposedly 3 years old. We took her to the Vet and the Vet listened to her heart and she has a large heart murmur. Pretty much there is nothing we can do for her unless we see her open mouth panting to rush her to a pet emergency center. will this effect her life span? Will it effect her daily living? She is a very high energy Cat and loves playing and wrestling with our dog and playing in water. We love her to death already in this short time we have had her.