Pitt-CMU Team Gets to Heart of It

Article excerpt

University of Pittsburgh biophysicist Guy Salama watched the electrical activity deep inside a living heart on a computer screen in his Oakland lab.

It's something that until recently couldn't be observed.

High-speed cameras recorded the impulses from a glistening pink mouse heart, which sat beating inside a plastic dish. The voltage changes appeared as wave-like squiggles on the computer screen.

New dyes invented in Pittsburgh are helping scientists see these voltage changes as they travel through the heart. Information about what occurs in the inner recesses of the heart could help researchers better understand the underlying causes -- and perhaps find better treatments -- for medical problems such as irregular heartbeats, or arrhythmias, that can lead to sudden death.

"This is going to be a major innovation for the future," said Salama, a professor in Pitt's department of cell biology and physiology. "At a certain point, you exhaust how much you can do by just looking at the surface of the heart. There is a big need for 3- D information."

More than 40,000 people in the United States die each year of arrhythmic episodes, which last month killed 28-year-old Maggie Dixon, sister of Pitt men's basketball coach Jamie Dixon.

"There are electrical disturbances of the heart that can cause fainting and sudden death," said Dr. Barry London, director of the University of Pittsburgh Medical Center Cardiovascular Institute. "For years we've been able to guess how that irregular activity happens, but we haven't been able to see it."

Since the late 1970s, scientists have tracked electrical activity in the heart using dyes that are sensitive to changes in voltage. The dyes emit fluorescent light that illuminates changes as they occur in fractions of seconds in the muscle cells at the organ's surface. …