Swedish researchers studied 2,83,014 heart attacks between 1998 and 2013 that were documented in a registry that included the date and time when symptoms started.
The risk of heart attack was the highest in people over 75, and those with existing diabetes and heart disease, which the researchers said highlights the need for more awareness around the issue, and the possible causes of stress.
The rise may also be linked to the flu season, which also raises the risk of heart attacks, particularly for over-65s with cardiovascular problems.
But they found the greatest risk by far was on Christmas Eve, where the chances of having a heart attack shot up by 37 percent.
On Christmas Day the risk was 29 per... Winston Churchill is said to have suffered a heart attack on December 26 in 1941 while opening a window at the White House following a speech to congress.
The scientists believe Christmas Eve (and other holidays) are times when people experience emotional stress, and that likely affects heart health - although they are only speculating. The study also noted more cases of heart attacks reported on Midsummer holidays, early mornings, and Mondays.
"Interestingly, the pattern of increased risk in the morning which dominates the rest of the year was reversed at Christmas, with an increased risk in the evening, indicating the stress and eating during the day triggered the heart attacks".
Previous studies have also shown a peak in heart attacks across the Western World during Christmas and New Year festivities, and during Islamic holidays in countries where the religion predominates, the study concluded.
"Understanding what factors, activities, and emotions precede these myocardial infarctions and how they differ from myocardial infarctions experienced on other days could help develop a strategy to manage and reduce the number of these events".