Kevin Lee, 17, has always found the heart interesting. "It maintains a steady rhythm for millions of beats," he says. Then, suddenly, "it can fail without any explanation." But three years ago, the heart-obsessed senior at University High School in Irvine, Calif., was no longer content to sit on the sidelines. "I saw all these stories in the news about these athletes suddenly collapsing and dying," he recalls. "I thought, if I could find the reasons why that could happen, I could find ways to treat those conditions and ways to prevent them."
This article was written by Bethany Brookshire for the Society of Science & the Public. Read the article at https://student.societyforscience.org/blog/eureka-lab/teen-finds-‘shape’-our-beating-hearts.
He hasn't succeeded. At least not yet. But Kevin has made some stunning progress, using math to show how the shape of the heart changes as it contracts, or beats. And he can now relate those changes to the electrical signals that tell the heart when it's time to beat.
Kevin presented his findings this week at the Intel Science Talent Search in Washington, D.C. Each year, Society for Science & the Public brings together 40 high school seniors to share their impressive research achievements with the public.The heart is made of strong, elastic and tough muscle. A bundle of cells inside the heart called the sinoatrial node sends out electrical signals directing the organ to contract. With each beat, the heart pumps blood in and out. Blood that is coming from the body circulates to the lungs where it takes up oxygen. Then it moves out and around to deliver that oxygen where it's needed. Throughout each contraction, the heart muscle radically changes its shape.
Current computer simulations of how the heart beats have been based on the pacing of the electrical signals from the sinoatrial node. But they don't include the changing shape of the heart muscle as it contracts. Kevin says those existing models rely on a string of polynomials. These are mathematical expressions (using only addition, subtraction and multiplication), and they must change at every time interval within a heartbeat. To understand heart motion, Kevin says, "you also have to account for the heart's elasticity, how it rebounds back...it just becomes a nightmare."
He decided to take a new approach. Kevin worked with partial differential equations. This alternative way allows him to mathematically express heartbeats and is specifically designed to include numbers that are constantly changing over time — like those numbers describing how a heart changes shape when it contracts. Instead of piling one type of mathematical expression atop another, partial differential equations allow the heart muscle and the electrical signals of the heartbeat to move together, Kevin explains.
The teen hopes that his model will help scientists better understand how the heart beats — and what happens when the muscle loses its regular rhythm. Those pacing problems, known as cardiac arrhythmias, can lead to severe health problems, and to the sudden death of the athletes that Kevin heard about on the news. By better understanding how heart signals relate both to the timing of heartbeats and the shape of a contracting heart, Kevin believes medical companies might be able to make drugs and devices that more safely and reliably stabilize unhealthy hearts.
Kevin Lee went on to win Second Place Honors in the 2014 Intel Science Talent Search, receiving $75,000.