I Have Congestive Heart Disease Which Seemed To Come Out

I have congestive heart disease which seemed to come out of nowhere very suddenly and I almost didn't make it to the hospital (in an ambulance) the Cardiologist I saw in the ER said he had to really work to keep me alive! I have no memory of most of the incident though I was the one who told my husband to call an ambulance. The doctor I saw in the ER is now my Cardiologist that I see twice a year. All has been well with my heart since then (I was 61 at the time of the incident). However, my recent visit to him showed that I have a leaky valve. I have had both him and my Primary explain what that means but I still don't really understand what it is, what caused it, and what can I expect in the future. I also need to mention that I am a woman about to turn 65 in February and also have "Non-Alcohol Cirrhosis of the Liver." What can you tell me about the "leaky" heart valve?
Linda C.