I had my pre-op appointment yesterday, and my blood oxygen saturation level was low, so they sent me for an echocardiogram. It showed that I have a congenital heart defect called patent ductus arteriosus. I'm going to see a cardiologist on Monday afternoon. This may or may not delay my hip surgery. I'll just have to wait and see what the cardiologist says and what the internist recommends. I'm still processing this new information.