PARIS • Joyful events - for example, the birth of a child or a big win by your team - can trigger a dangerous condition called "broken heart syndrome", doctors and researchers have reported.
Takotsubo Syndrome (TTS), as it is also known, involves the sudden weakening of heart muscles, causing the left ventricle - the chamber which pushes oxygen-rich blood through the body - to balloon out abnormally at the bottom.
Besides acute chest pain and shortness of breath, the condition can lead to heart attacks and death.
The condition - discovered by Japanese researchers - gets its name from a traditional Japanese octopus trap, which is said to resemble the distended heart chamber.
It has long been known that an unexpected emotional shock - typically something unpleasant - can provoke an attack. But statistics were lacking, and no one had ever investigated whether an intensely happy event could give the same result.
In 2011, Swiss researchers Christian Templin and Jelena Ghadri, both of University Hospital Zurich, set up a global registry to track cases of TTS, which is fairly rare. Five years later, it had collected data on 1,750 cases of TTS.
For the study, the duo determined that emotional jolts were responsible for 485 of those cases. And within that group, 4 per cent - a total of 20 individuals - suffered from "happy heart syndrome".
"We have shown that the triggers for TTS can be more varied than previously thought," said Dr Ghadri. "The disease can be preceded by positive emotions, too."
The 20 cases set off by joyful events included a birthday party, wedding, surprise farewell celebration, favourite rugby team winning a game, and the birth of a grandchild. None of them proved fatal.
Emergency doctors should be aware of the fact that patients with signs of heart attack could be suffering from TTS sparked by either positive or negative experiences.
For reasons the researchers do not understand, 95 per cent of the patients in both the broken heart and happy heart groups were mostly women in their mid to late 60s. "We can only speculate that the hormonal state - namely, oestrogen - might play a role in the disease mechanism," Dr Ghadri said.