Watching stressful or emotionally charged movies can lead to small and harmless changes in heartbeat along with significantly high blood pressure.
Researchers from the University College London found that watching a stressful movie may lead to minute abnormalities in regular heartbeat, resulting in a significant increase in blood pressure. The researchers clarified that the changes in heartbeat were small and not likely to be risky.
"Our findings help us to better understand the impact mental and emotional stress can have on the human heart," Dr Ben Hanson (UCL Mechanical Engineering) explained in a news release. "This is the first time that the effects have been directly measured and although the results varied from person to person we consistently saw changes in the cardiac muscle. If someone already has a weakened heart, or if they experience a much more extreme stress, the effect could be much more destabilizing and dangerous."
For the study, 19 patients undergoing routine cardiac catheterization treatment using local anesthetic were shown clippings from the Hollywood film "Vertical Limits."
"Film clips are considered to be among the most powerful stimuli to elicit affective responses in the laboratory setting and have several advantages including their dynamic nature, a sustained effect and the combination of visual and auditory inputs," said study author Professor Peter Taggart (UCLH Neurocardiology Unit).
Electrodes were placed in the ventricles of the heart to measure the changes in cardiac muscle, whilst the team simultaneously recorded changes to blood pressure and breathing speed. Researchers noted slight changes in heartbeat and a significant increase in blood pressure while the participants watched the clips.
For the second part of the study, the same participants were asked to repeat the breathing pattern they had while watching the film. This time, researchers didn't observe any irregularity in heartbeat nor did they find any change in blood pressure.
"This is the first study where the direct effect of mental and emotional stress on the heart has been observed. It helps us understand the mechanisms involved. Our results are really very exciting," the researchers noted.
The study was published online in the journal Circulation: Arrhythmia and Electrophysiology.
