“Broken-heart syndrome” can appear so similar to a heart attack that physicians often must perform invasive tests to distinguish the two, but researchers have now designed an index called BioTAK that, by combining a person’s sex and biomarkers present in the blood, identifies the condition before performing invasive coronary angiography (cardiac catheterization). In a validation study on nearly 1,800 patients, this index correctly identified the status of about 90 percent of participants.
Takotsubo syndrome, also known as broken-heart syndrome, is a type of sudden heart condition that primarily affects postmenopausal women and may arise from severe emotional or physical stress. About 2 percent of patients initially thought to have a heart attack actually have this syndrome. That proportion among women with acute coronary syndrome may reach one in ten. However, in the early stages of evaluation, distinguishing this syndrome from a heart attack is very difficult.
People with takotsubo syndrome may suddenly experience chest pain, abnormal electrocardiogram results, and elevated cardiac enzyme levels-signs that closely resemble heart attack symptoms. The main difference is that in takotsubo syndrome, the coronary arteries are not obstructed.
According to ScienceDaily, because the two conditions initially look almost identical, many patients undergo invasive cardiac catheterization before physicians determine the cause of their symptoms.
A new method to identify takotsubo syndrome
An international group of researchers, in close collaboration with scientists from the Universities of Zurich and Greifswald, has designed and validated a diagnostic scoring system aimed at identifying takotsubo syndrome prior to catheterization.
This new tool, called the BioTAK index, combines sex with several blood biomarkers related to different cardiovascular processes. Using artificial intelligence, the researchers determined which combination of biomarkers provided the most useful diagnostic information and then incorporated those markers into a clinical decision-making tool.
The BioTAK index identified takotsubo syndrome with high accuracy in an independent cohort of nearly 1,800 other patients. Using predefined thresholds, the system correctly identified the status of nearly 90 percent of participants prior to cardiac catheterization.
Florian A. Wentzell, one of the two first authors of the study from the Center for Molecular Cardiology at the University of Zurich and the Radcliffe Department of Medicine at the University of Oxford, said: “Our study shows that a simple combination of blood biomarkers and sex can identify these patients with remarkable accuracy even before cardiac catheterization.”
Viktor Schweiger, the other first author of the study from the University Hospital Zurich, added: “These biomarkers also provide information about the biological processes that distinguish takotsubo syndrome from a typical heart attack.”
Clues of a brain–heart connection
Beyond its potential diagnostic value, the BioTAK index also offers new information about the biological mechanisms of takotsubo syndrome. Two newly identified biomarkers included in the index point to an important role for the “brain–heart axis” and indicate that this condition arises through mechanisms different from atherosclerosis.
One of these proteins helps activate a set of neuropeptides involved in stress responses, anxiety, regulation of vascular contraction and dilation, and autonomic nervous system activity. The other protein is associated with the stability of plaques caused by atherosclerosis. Together, these two markers reveal a biological pattern that differs fundamentally from the typical pattern in classic heart attacks.
Thomas Lüscher, one of the two senior authors of the study, explained: “The BioTAK index, by capturing signaling pathways related to stress responses, cardiac dysfunction, and plaque stability, turns complex disease mechanisms into a practical diagnostic tool.”
Potential application in emergency care
The researchers say the BioTAK index could become a useful tool for the initial assessment of patients who present to the emergency department with possible acute coronary syndrome.
Christian Templin, the other senior author of the study, said: “The BioTAK index is not a replacement for cardiac catheterization when catheterization is medically necessary. However, it could help guide the diagnostic process more effectively and prevent unnecessary invasive tests for some patients.”
He added: “Our aim is that in the future we will identify patients with takotsubo syndrome earlier and with greater confidence, while also gaining a better understanding of the underlying mechanisms of this disease.”
Further research will examine whether adding the BioTAK index to routine clinical care can improve the diagnosis and treatment of takotsubo syndrome.