Intense Movies May Be Dangerous for People With Weak Hearts

It’s no surprise to anyone who’s felt their heart jump into their throat while watching a scary movie that these scenes can be stressful. But can that stress be measured by scientists — and is it dangerous?

In a small study published yesterday in the American Heart Association journal Circulation: Arrhythmia and Electrophysiology, researchers tracked how emotional stress — in this case, watching a harrowing five-minute clip of the rock-climbing movie Vertical Limit — affects the heart. They measured the blood pressure, heart rhythm and breathing speed of 19 heart patients while they watched the scene and found that the clip affected the stability of their heart beat while also increasing blood pressure and how quickly the patients were breathing.

“If someone already has a weakened heart, or if they experience a much more extreme stress,” said study author Dr. Ben Hanson of University College London, “the effect could be much more destabilizing and dangerous.”

(Researchers recreated those breathing patterns without subjecting the patients to the clip and found no such change in heart rate, suggesting that the emotional stress — and not just the increased respiration — was to blame.)

In a statement about the study, Dr. Ben Hanson, one of its authors, said that the results did vary but the observation of cardiac changes was consistent. So, though there’s no reason for healthy movie fans to worry, those with preexisting heart problems might want to take it under consideration.

Watch the clip at your own risk here: