Can cancer break your heart? A new study suggests that there's a link between cancer and a condition called broken heart syndrome.
The study, published Wednesday in the Journal of the American Heart Association, found that 1 in 6 people with broken heart syndrome had cancer, and that these patients in particular were more likely to die within five years, compared with broken heart syndrome patients without cancer.
Broken heart syndrome, which is also called stress cardiomyopathy or takotsubo cardiomyopathy, is a temporary condition that can be brought on by stressful situations. During broken heart syndrome, one part of the heart stops pumping normally, which may cause the rest of the heart to pump more forcefully, according to the Mayo Clinic.
A study from 2018 found that patients diagnosed with broken heart syndrome were twice as likely to face clinical complications during their treatment if they also had a history of cancer. That finding prompted the investigators to see if there was a connection between the two conditions.
In the new study, the researchers looked at data from the International Takotsubo Registry on more than 1,600 patients with broken heart syndrome. They found that 1 in 6 had cancer. Of those with cancer, nearly 90 percent were women. The most frequent type of cancer was breast, followed by the gastrointestinal system, respiratory tract, internal sex organs, skin and other areas.
Compared to those without cancer, broken heart syndrome patients with cancer were:
- Almost twice as likely to have experienced a physical trigger versus an emotional trigger of broken heart syndrome.
- Just as likely to survive for 30 days after the syndrome began, although more likely to die or require intensive heart and respiratory support while in the hospital.
- More likely to die within five years after the syndrome began.
The study only found a link between cancer and broken heart syndrome; it does not show that one causes the other. However, that's an area where more research is warranted, the study authors say.
“The mechanism by which [cancer] and cancer treatment may promote the development of broken heart syndrome should be explored, and our findings provide an additional reason to investigate the potential cardiotoxic effects of chemotherapy,” the study's lead author, Dr. Christian Templin, director of Interventional Cardiology of the Andreas Grüntzig Heart Catheterization Laboratories at the University Heart Center Zurich at The University Hospital Zurich in Switzerland, said in a statement
“Our study ... should raise awareness among oncologists and hematologists that broken heart syndrome should be considered in patients undergoing cancer diagnosis or treatment who experience chest pain, shortness of breath or abnormalities on their electrocardiogram,” Templin said. Similarly, “patients with broken heart syndrome might benefit if screened for cancer to improve their overall survival,” he said.
Broken heart syndrome
The condition was first identified in Japan in 1990, where physicians noticed people with heart attack symptoms but, upon further testing, none of the signature blood clots that cause heart attacks.
Instead, the condition is triggered when a severe stressor — such as financial loss, a fierce argument or a natural disaster — causes physical damage to the heart. Cardiomyopathy ensues, because the heart’s main pumping chamber temporarily enlarges and doesn’t pump well. The syndrome feels like a heart attack, with chest pain and shortness of breath, but there is no heart muscle damage and no blockage in the coronary arteries feeding the heart.
Increased levels of stress hormones are thought to be one of the main drivers of broken heart syndrome. And some experts believe that cancer may also play a role.
“The interplay between the two is unclear, but many cancer treatments can also have an effect on the heart,” said Dr. Laxmi Mehta, director of preventative cardiology and women’s cardiovascular health at Ohio State University.
Mehta, who was not involved with the new research, added that it's important to look at the patient as a whole. “Many of the risk factors between cancer and cardiovascular disease overlap, such as smoking, family history, poor diet and lack of exercise,” she said.
Prior research has shown that treatment with certain cancer drugs has been associated with the syndrome, particularly 5-fluorouracil and rituximab, but the exact reason why this occurs in some people has been elusive.
Because of this, “if someone has underlying heart disease and a history of cancer, they need to see their cardiologist and discuss if the drugs they’re taking are OK to continue taking,” Mehta said.
Dr. Francesco Santoro, a cardiologist at the University of Foggia in Italy and a leading expert in broken heart syndrome, said that he also wasn’t quite sure why those with cancer fared worse after suffering broken heart syndrome than those without cancer. But he noted that “more research needs to be done to clarify the reasons for this, and if a combination of standard heart failure drugs may provide a benefit.”
“I don't have any tricks, but if a patient with heart break syndrome doesn't have a clear stressor, then maybe doctors should look for cancer,” he said.