A new blood test may reveal whether patients are in imminent danger of having a heart attack, according to a new study.

Scientists compared blood samples of 50 heart attack patients with 44 healthy participants, and found significantly higher concentrations of abnormal circulating endothelial cells, or CECs in heart attack patients. 

Researchers said that the heart attack patients in the study had five times more abnormally shaped versions of CECs that have multiple nuclei circulating in their blood compared to healthy participants.

CECs are a type of cell that lines the arteries in blood controls the ability of arteries and veins to widen and prevent clots.  Researchers said that because these cells are most likely released by ruptured arteries in the weeks leading up to a clot formation and then a heart attack, the warning signs could be identified as they accumulate.

"The ability to diagnose an imminent heart attack has long been considered the holy grail of cardiovascular medicine," principal investigator Dr. Eric Topol and director of the Scripps Translational Science Institute said in a statement released on Wednesday. 

According to the U.S. Centers for Disease Control, heart disease is the leading cause of death in the United States, and more than a million Americans experience a heart attack every year.

Researchers say that people often go to the hospital when they have chest pain or pressure, only to be sent home when doctors fail to detect a problem after conducting tests like electrocardiograms, which measure irregular heartbeats and heart damage.

Experts said that the blood test could be developed for commercial use in the next year or two if the latest findings are confirmed. The test would be performed in an emergency room to determine whether patients are “on the cusp of a heart attack or about to experience one in the next couple of weeks,” Dr. Raghava Gollapudi from the company Sharp HealthCare, who took part in the research said in a statement.

“Right now we can only test to detect if a patient is currently experiencing or has recently experienced a heart attack,” Gollapudi added.

"This is an interesting study and represents a new approach to trying to predict who might be at risk of an impending heart attack,” Professor Peter Weissberg, medical director at the British Heart Foundation, said in a statement released on Wednesday.

"However, the current study only shows that patients in the throes of a heart attack have abnormal cells. It does not show that such cells were present before the heart attack started. This will have to be explored in future studies.  It will also be important to show that the abnormal cells only appear during a heart attack and are not also present in other illnesses," Weissberg added.

The findings are published in the journal Science Translational Medicine.

Other British experts are “suspicious” about the strength of the new study, and said that European studies have already identified a much more reliable sign of impending heart attacks.

"I would be very suspicious about any finding that had not been demonstrated to be predicted by taking the blood before the heart attack,” Professor John Martin, a cardiac specialist from University College London said, according to The Telegraph.

He said that there was much better evidence that the buildup of large clotting agents called platelets could cause the development of heart attacks.

"The evidence for large platelets in the circulation being causally related is far stronger than this and is based on more credible rationale," Martin said.