Researchers looking to help those with heart arrhythmia

As many as six million Americans suffer from heart arrhythmia, a condition where the heart beat is irregular, or skips a beat.

It contributes to more than 130,000 deaths every year.

Researchers in the United States and Germany are looking at a gentle option to put hearts back in sync.

Every year, thousands of Americans suffer sudden cardiac arrest. For many, an implantable defibrillator puts the heart’s electrical system back in rhythm. It's a life-saving technique, but biomedical engineering professor Natalia Trayanova, PhD at Johns Hopkins University describes its problems. “If it discharges, then it is very, very painful and feels like a horse kicking you in the chest.”

Patrick Boyle, PhD is an assistant research professor, also at Johns Hopkins University. He describes how the defibrillator works: “When a large electrical shock is delivered, for example, part of the reason why it’s so painful is that it causes all the muscles around the heart to contract.”

Trayanova and Boyle have been working with researchers in Bonn, Germany, and they’ve found another way. Instead of electricity, they say light may be a better option. The Bonn team tested the theory in animals.

“They did experiments in mice in which they embedded these light sensitive proteins and they delivered light from the outside of the heart and they were able to terminate or defibrillate the arrhythmia," explains Trayanova.

The Johns Hopkins team then used a computer model of an actual heart to see if a dose of red light would regulate the much larger human organ, and it does.

Trayanova explains, “The steps that have been taken in the past few years are major. This is a major milestone.”

Researchers say someday, instead of a major blast to the heart, a gentle light will be all a patient may need.

The Johns Hopkins team envisions a pacemaker-like implantable device that would someday deliver the light pulse from within the body, when it senses the person’s heart is out of rhythm.

RESEARCH SUMMARY

TOPIC: Light Puts Hearts in Rhythm

REPORT: MB #4188

BACKGROUND:

Arrhythmias can produce a broad range of symptoms, from hardly noticeable to resulting in a heart attack or death. These are premature heart beats that can be felt as a “palpitations” or feeling like the heart “skipped a beat.” Those that occur often or in rapid succession may cause a “fluttering” sensation in the chest or neck. When they last long enough to affect how well the heart works, more serious symptoms may develop. These include fatigue, dizziness, lightheadedness, fainting, rapid heartbeat or pounding, shortness of breath, chest pain, and in severe cases collapse and sudden cardiac arrest.

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TREATMENTS:

Slow heartbeats that don’t have a cause that can be corrected will often be treated with a pacemaker. A pacemaker is a small device that's usually implanted near the collarbone. One or more electrode-tipped wires run from the pacemaker through the blood vessels to the inner heart. If the heart rate is too slow or if it stops, the pacemaker sends out electrical impulses that stimulate the heart to beat at a steady rate. Fast heartbeats may be treated with medications, cardioversion (shock delivered to your heart through paddles), and several other methods including surgery or implantation of a pacemaker.

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