Every day, cardiologists make decisions about what is the most appropriate test, therapy or procedure for their patients. And when they make those decisions, they are guided by years or sometimes decades' worth of research into what's the best course of action--or at least we hope they do. But then COVID-19 came along. And the more we learned about how the virus wreaks havoc on the cardiovascular system, many of us started to wonder: Have the rules of the game changed?