I am an open heart recovery nurse and definitely if you had the craving for the heart and cath lab it is one of the greatest experiences to learn and knowledge you will use constantly. The heart is fascinating and each one is unique with its own specific problems....and a adrenalin rush is a sure thing - not with each case but it happens.....It sounds like something to add for you never stop learning in this field. Just don't let them keep adding more extra time - you will get it more often than not being called in on call time. Go in with a positive exciting time awaiting you. Hope your cath lab is as great as ours. We all work so well as a team player in each persons condition. Good Luck!