Right now, about six million Americans are living with heart failure, in which the heart loses its ability to pump strongly enough to meet the body's need for blood and oxygen. And about 450,000 die from it each year.
Sometimes heart failure comes on for no reason — or so it seems. Mario J. Garcia, M.D., right, aims to convince these "normal" hearts to reveal their secrets.
"Many patients have subtle abnormalities of heart function that until recently haven’t been detected," says Dr. Garcia, the new chief of the Einstein/Montefiore division of cardiology and codirector, with Robert E. Michler, M.D., of the Montefiore-Einstein Center for Heart and Vascular Care. Dr. Garcia was recruited last year from Mount Sinai Medical Center, where he oversaw the cardiac imaging program.
He can now be found where the machines are: at Montefiore Medical Center, the University Hospital and Academic Medical Center for Einstein, or at the Gruss Magnetic Resonance Research Center (MRRC).
Together, they offer a complete menu of imaging options, from state-of-the-art patient angiography, echocardiography (ultrasound) and MRI, CT and nuclear imaging to advanced systems for research studies.
"There are very exciting developments in echocardiography, the area where I've worked the longest," says Dr. Garcia, Einstein's Pauline A. Levitt Chair in Medicine and professor of radiology. Working with computer specialists and biomedical engineers, Dr. Garcia measures the velocity of blood flow through the chambers of a patient's heart. Then, using hemodynamic equations, he calculates the resulting pressures within the heart, all without invasive catheterization. With this information, he says, it’s possible to estimate how efficiently the heart beats.
Or consider an older man complaining of fatigue and shortness of breath during physical activity — a sign of heart failure. According to Dr. Garcia’s recent research, cardiac fibrosis (scarring of the heart muscle) could be involved.
Cardiac fibrosis is a well-known legacy of a past heart attack but may also develop for hidden reasons, in both men and women.
"Using cardiac MRI, we've been able to identify and characterize how fibrosis develops," says Dr. Garcia. Fibrosis is present in about 80 percent of all cases of hypertrophic cardiomyopathy, the heart enlargement that leads to heart failure and often sudden death — even without a heart attack. Using the new 3 Tesla Philips magnetic resonance system at the Gruss MRRC, "we can work faster and at higher resolution, identifying scars as small as 1 millimeter long," he says.
The next step: to understand how fibrosis and heart enlargement occur and develop therapies to treat these problems — and help that older man resume his workouts.
Posted on: Thursday, October 27, 2011