Before filling one of these tubes with blood for a cholesterol test, you're supposed to keep your stomach empty. But that may not be necessary. Nancy Louie/iStockphoto.com hide caption

itoggle caption Nancy Louie/iStockphoto.com

This gentleman may want to have a chat with his cardiologist. Bill Losh/Getty Creative Images hide caption

itoggle caption Bill Losh/Getty Creative Images

Members of the online community Track Your Plaque get advice from a doctor and each other on how to cook low carb meals. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Pedometer, an app, keeps track of your steps, distance traveled and calories burned. Benjamin Morris/NPR hide caption

itoggle caption Benjamin Morris/NPR

Hugo Campos' implantable cardioverter-defibrillator was a mystery to him. So he decided to ask his doctor for access to the data. He made this image with one of his own X-rays. Hugo Campos hide caption

itoggle caption Hugo Campos

Katherine Leon says she spends up to 12 hours a day online interacting with others who share her rare heart condition. Emily Bogle/NPR hide caption

itoggle caption Emily Bogle/NPR

Becky Cole was eight months pregnant with her son Ryan when she passed out. Her husband performed CPR for six minutes with the help of a dispatcher before medics arrived. Courtesy of Medic One Foundation hide caption

itoggle caption Courtesy of Medic One Foundation

Karlton Hill, 15, was diagnosed with diabetes when he was 12. He works hard to manage the disease: He jogs and does pushups every day; he takes metformin is very careful about what he eats. Leslie Capo/LSU Health Sciences Center hide caption

itoggle caption Leslie Capo/LSU Health Sciences Center