Cheney Expert News Today

Former president george w. bush and from vice president biden. to the average person, that sounds pretty remarkable. so i did want to bring in our medical correspondent, dr. sanjay gupta. and along with sanjay, we have a cheney expert. he is truly an expert, barton gellman. san sanjay, let me start with you. when i found out today this was a heart attack, i thought, how does anyone survive five heart attacks? is this relatively rare or more common than we think? >> its more common than you think...