Illustration by Rashid Alavi of device design to notify patients of ultra-silent heart attacks

“Heart attacks are one of the leading causes of death worldwide, with an estimated 8.5 million acute heart attacks occurring worldwide each year, with mortality rates of up to 10% after one month and 10% after one year. The mortality rate is up to 25%.” Rashid Alavi is the lead author of the paper presented at the European Society of Cardiology. However, a heart attack may not be accompanied by chest pain or appear in the ways that people are used to seeing in the media.

More statistics frame the risk: The first hour of a heart attack (myocardial infarction) represents a critical window for reducing mortality and improving patient survival (1 ). Heart attacks have traditionally been detected based on clinical symptoms such as chest pain and electrocardiogram criteria. Silent heart attacks (heart attacks without chest pain) account for nearly 50% of all heart attacks and are more common among people with diabetes and the elderly (2, 3). Additionally, nearly half of these patients have nondiagnostic electrocardiograms, referred to as “super-silent” heart attacks (4).

That’s what motivated Alavi, who was a doctoral student in mechanical engineering within the Medical Flow Physics Laboratory (MFPL) at the USC Michelson Center for Convergent Biosciences, to tackle this problem. The sooner the heart muscle is treated, Alavi said, the better the chance of survival. What if a non-invasive device could provide immediate critical warnings to people at risk?

Led by Professor Neema Pahlevan, USC’s Gordon S. Marshall Early Career Chair in Engineering and Assistant Professor of Aerospace, Mechanical Engineering, and Medicine, the new patent-pending methodology developed by the lab replaces the required existing diagnostic tools. provide the means. It can be either an expensive medical device such as an electrocardiogram, an implanted device, or a blood test that looks for proteins released during cardiovascular events such as a heart attack. Researchers have developed an “immediate, inexpensive, non-invasive method” to detect heart attacks independent of chest pans and electrocardiograms.

The methodology developed by engineers in collaboration with Huntington Medical Institute and Keck School of Medicine of Southern California clinicians Robert Kroner, Dai Wende, and Ray Matthews allows smartphone cameras and wearable devices to detect heart attacks ( Silent, Super) can now be detected. silent or periodic) from what is known as the neck pulse, or “carotid artery pressure waveform that pulsates the skin of the neck.”

Professor Parlevan summarizes the technology as follows: “Because we use a new physics-based index (or hemodynamic signature) extracted from the pressure waveform, our method relies on changes in the mechanical activity of the heart after a heart attack.” added that the technology is “independent of the heart’s electrical activity.” Rather, it relies on customized algorithms that interpret hemodynamic data and predict whether a heart attack has occurred. “Hospitals and medical centers are good at minimizing the time between when a heart attack patient arrives at the hospital and when the patient is treated with stents and balloons that widen blood vessels in the heart,” Parlevan said. . He added: “Unfortunately, heart attack patients spend too much time at home thinking about their symptoms, which exceeds the time between arriving at the hospital and receiving critical life-saving treatment.” .

Although this study was a preclinical study in animals and demonstrated successful validation of the team’s new AI-based technology, the researchers hope to begin the clinical trial phase. This step aims to transform this technology for use by clinicians and health professionals, and ultimately for everyone in the home. Now a graduate, Alavi continues her research as a James Boswell Postdoctoral Fellow at the California Institute of Technology.

1. Cannon CP, Gibson C, Lambrew CT, et al. Relationship between symptom onset and balloon time and door-to-balloon time and mortality in patients undergoing angioplasty for acute myocardial infarction. jam. 2000;283(22):2941-7.

2. Benjamin EJ, Blaha MJ, Chiuve SE, Cushman M, Das SR, Deo R, et al. Heart disease and stroke statistics – 2017 update: American Heart Association report. Circulation. 2017;135(10):e146-e603.

3. Zhang ZM, Rautaharju PM, Prineas RJ, Rodriguez CJ, Loehr L, Rosamond WD, et al. Racial and gender differences in the incidence and prognostic significance of silent myocardial infarction in the Atherosclerosis Risk in Communities (ARIC) study. Circulation. 2016: Circulation ah. 115.021177.

4. McCain FH, Klein EM, Gilson JS. A clinical study of 281 autopsies of myocardial infarction patients has been reported. American Heart Journal. 1950;39(2):263-72.

Published April 7, 2024

Last updated: April 7, 2024