can either erosion of slippage like be fatal??? that scares me!!!

Life alone can be fatal! But slippage & erosion aren't usually considered emergency problems. Any surgery can be fatal considering the risks of anesthesia, and I suppose doctor error could be a problem. But so far I don't think anyone would consider band related complications fatal.

Lisa's right, the complications themselves aren't fatal. If they cause big problems like being unable to eat or drink, ignoring them might lead to bigger problems. But neither is something that would kill you without your having some BIG signals that something else is wrong. There'd be plenty of time to get whatever was wrong, fixed.