These are the days of miracle and wonder, particularly for emergency room doctors, who wonder how many more cardio patients will come through their doors. A 2008 study published in Congestive Heart Failure found that visits to hospitals for heart failure increased by 33 percent during the four days after Christmas. Health.com cites that study and another 2004 study published in Circulationthat found that heart-related deaths increase by nearly 5 percent during the holidays. Why? Holiday’s are fun, but they’re also stressful. Let’s face it: Santa is weird, and it’s easy to eat and drink more than is heathful. Health.com points out that cold weather may also play a role, because blood vessels constrict, raising blood pressure, when the temperature drops.