Gentle beams of light could replace harsh electric shocks in patients reeling from a deadly heart rhythm disorder, new research has found. Current devices deliver pulses of electricity that are extremely painful and can damage heart tissue.
Light-based treatment should provide a safer and gentler remedy for patients at high risk of arrhythmia, an irregular heartbeat that can cause sudden cardiac death within minutes, the researchers said.
To move the new heart treatment closer to reality, the scientists at Johns Hopkins and Germany's University of Bonn focused on two different types of research. The Bonn team conducted tests on beating mouse hearts whose cells had been genetically engineered to express proteins that react to light and alter electrical activity within the organ. When the researchers triggered ventricular fibrillation in a mouse heart, a light pulse of one second applied to the heart was enough to restore normal rhythm.
To find out if this technique could help human patients, the Johns Hopkins team performed an analogous experiment within a detailed computer model of a human heart, one derived from MRI scans taken of a patient who had experienced a heart attack and was now at risk of arrhythmia. "Our simulations show that a light pulse to the heart could stop the cardiac arrhythmia in this patient," Patrick Boyle from Johns Hopkins University said.
