WASHINGTON (AP) 鈥� Scientists created virtual replicas of patients鈥� diseased hearts so precise that blocking a dangerous irregular heartbeat in these digital 鈥渢wins鈥� showed doctors how to better treat the real thing.
One of the first clinical trials of these custom models suggests it might improve care for , a notoriously difficult-to-treat arrhythmia that is a major cause of sudden cardiac arrest, blamed for about 300,000 U.S. deaths a year.
The study, by researchers at Johns Hopkins University, was a small first step. The Food and Drug Administration allowed the digital twin technology to guide treatment for just 10 patients, and much larger studies will be needed.
But the results reported Wednesday in the New England Journal of Medicine come as doctors increasingly are exploring how a technology long used in aerospace and other industries might be harnessed for better health, too.
Dr. Jeffrey Goldberger, a heart specialist at the University of Miami who wasn鈥檛 involved with the study, experimented with more rudimentary iterations 15 years ago and praised the new findings. 鈥淭his is what we envisioned,鈥� he said.
Doctors have long used 3D models, both physical and computer-generated ones, to simulate disease and practice techniques. But Hopkins biomedical engineer Natalia Trayanova said true digital twins predict how a real organ can react to different treatments. Her lab is pioneering colorful interactive models developed with an advanced MRI scan and other data from each patient.
鈥淲e treat the twin before we treat the patient,鈥� Trayanova said. 鈥淒id it work? And if it did, are there new things that arise鈥� that will require more or different care?
The heart鈥檚 electrical system powers our heartbeat. Ventricular tachycardia is a super-fast heartbeat triggered when an electrical wave short-circuits in the organ鈥檚 bottom chambers, the ventricles, and prevents them from pumping blood out to the body.
鈥淵ou see this heart that is basically quivering,鈥� Trayanova said.
Medication can help but the main treatment is ablation, when doctors thread catheters to the heart to burn misfiring tissue. But it’s a bit trial-and-error, as patients spend hours under anesthesia while doctors determine where to aim. Repeat ablations are common, and many patients have an implanted defibrillator as backup.
Enter Trayanova鈥檚 digital twins of patients鈥� ventricles. Colors swirl on a computer screen 鈥� blue, green, yellow and orange 鈥� showing how the heart鈥檚 electrical wave moves across the chamber鈥檚 healthy areas before getting stuck on damaged tissue. It鈥檚 trapped in a circular motion that she compares to the swirl of a hurricane.
鈥淚t allows me to recreate the functioning of the patient鈥檚 organ and then predict what is the best way to ablate,鈥� she said.
The technology locates a dysfunctional region where the electrical wave repeatedly hits. Virtually ablating it will show if that solves the problem or if another arrhythmia forms that also will need zapping. 鈥淭hen we poke it again,鈥� she explained.
Trayanova鈥檚 team created customized ablation targets for each of the 10 study participants. Cardiologists transferred them to a mapping system they use as a guide and aimed just at those targets instead of hunting their own.
More than a year later, eight patients had no arrhythmias while two experienced only a single brief episode while they were healing — better than the treatment鈥檚 typical 60% success rate, said Dr. Jonathan Chrispin, a Hopkins cardiologist and the study鈥檚 lead author. All but two also stopped their anti-arrhythmia medicine.
More importantly, cardiologists may burn away less tissue by targeting “specifically the areas that we think are critically important,鈥� Chrispin said. 鈥淲e could potentially make these procedures shorter, safer, more effective.鈥�
The Hopkins team hopes to study the digital twin approach in a larger study with other hospitals, and has begun a trial using it to treat a more common type of irregular heartbeat called atrial fibrillation. Other researchers are studying digital twins for cancer care.
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