New laser light diagnostic tool quickly detects early signs of heart attack

In the event of a heart attack, every second counts. A new blood test can diagnose them in minutes rather than hours and could be adapted as a tool for first responders and people at home.

“Heart attacks require immediate medical intervention to improve patient outcomes, but while early diagnosis is essential, it can also be very difficult and almost impossible outside of a clinical setting,” said the lead author Peng Zheng, an assistant research fellow at Johns. Hopkins University. “We were able to invent new technology that can quickly and accurately determine whether a person is having a heart attack.”

The proof-of-concept work, which can be modified to detect infectious diseases and cancer biomarkers, is recently published in Advanced science.

Zheng and lead author Ishan Barman are developing diagnostic tools through biophotonics, using laser light to detect biomarkers, which are bodily responses to conditions including diseases. Here, they used the technology to detect early signs in the blood of a heart attack.

Although approximately 800,000 people suffer a heart attack each year in the United States alone, heart attacks remain one of the most difficult conditions to diagnose, with widely varying symptoms and biological signals that can be subtle and easy to ignore in the early stages of the disease. an attack, when medical intervention can do the most good.

People suspected of having had a heart attack usually undergo a combination of tests to confirm the diagnosis, usually starting with electrocardiograms to measure the heart’s electrical activity, a procedure that takes about five minutes, and blood tests to detect the characteristics of a heart attack. , where lab work can take at least an hour and often needs to be repeated.

The standalone blood test created by the team provides results in five to seven minutes. According to the researchers, this method is also more precise and more affordable than current methods.

Although created for rapid diagnostic work in clinical settings, the test could be adapted as a portable tool that first responders could use in the field, or that people could even use themselves at home.

“We’re talking about speed, precision and the ability to make measurements outside of a hospital,” said Barman, a bioengineer in the Department of Mechanical Engineering. “In the future, we hope this can become a handheld instrument like a Star Trek tricorder where you take a drop of blood and voilà, within seconds you have detection.”

The heart of the invention is a tiny chip with a revolutionary nanostructured surface on which blood is tested. The chip’s “metasurface” enhances electrical and magnetic signals during Raman spectroscopy analysis, making heart attack biomarkers visible within seconds, even at ultra-low concentrations. The tool is sensitive enough to flag heart attack biomarkers that might not be detected at all with current tests, or might not be detected until much later in an attack.

Although designed to diagnose heart attacks, this tool could be adapted to detect cancer and infectious diseases, the researchers say.

“There is huge business potential,” Barman said. “Nothing limits this platform technology.”

Next, the team plans to refine the blood test and explore larger clinical trials.

The authors included Lintong Wu, Piyush Raj, Jeong Hee Kim, Santosh Paidi, all of Johns Hopkins, and Steve Semancik, of the National Institute of Standards and Technology.