"So I can walk on a treadmill, but I can't run. I can exercise, but not vigorously," said heart patient John DeFord.
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His condition is being fixed, but first, cardiologists need a picture of his heart. They're using a new CT scanner, one of the most powerful in the world, it can capture an image in less than a second.
"The most unique part is taking a picture of the heart in one heartbeat or less," said Cardiologist Richard George from Johns Hopkins University.
The new scanner collects enough data to produce a three-dimensional image of almost any organ in the body.
"One of the most exciting things is getting a more accurate image that is easier to analyze and an image that we trust our results that we're reporting," said Dr. George.
The new scanner can produce 320 or an even 640 cross-sectional images or slices. Then a computer stacks up the slices to create 3D pictures.
Doctors can better see subtle changes in blood flow or blockages forming in tiny blood vessels in organs, with amazing detail and accuracy.
"We can actually spin this around to see another artery," said Dr. George.
Compared to previous generations of the same machine, the one second scan exposes patients to less radiation because the less time you spend getting a scan the less expose you get.
The speed of the exam also allows more patients to receive the scan. The faster John gets a heart scan, the sooner he can be treated.
"I'm hoping to get my life back," said DeFord.
The new 320-slice CT is only in use in five places in the world. One at Johns Hopkins in Baltimore, Brigham and Women's Hospital in Boston, in Toronto Canada and in Germany.
Web Extra Information: One second heart scans
WHAT IS ARRHYTHMIA?
An arrhythmia occurs when the heart beats too fast, too slow, or irregularly. This keeps the heart from pumping blood properly. Normally, the heartbeat starts in the right atrium, when a special group of cells (the "pacemaker" of the heart) sends an electrical signal causing the muscles to contract. These signals travel through connecting fibers to all parts of the ventricles and must follow the exact route in order for the heart to pump properly. There are many types of arrhythmias, which are identified by where they occur in the heart (in the atria or ventricles), and by what happens to the heart's rhythm when they occur. One example is atrial fibrillation, an irregular heartbeat that interferes with the heart's ability to pump blood. Abnormal electrical signals cause the atria, or upper chambers of the heart, to contract erratically. Blood then pools in the atria and forms clots. These can travel to the brain and cause a stroke. The most serious arrhythmia is ventricular fibrillation, where the lower chambers quiver and the heart can't pump any blood. This can result in collapse and sudden death if there isn't immediate medical attention.
HOW CT SCANS WORK:
CT scans use X-rays to image the body. X-rays can pass through most materials. It all depends on the size of the atoms that make up the material; larger atoms absorb X-ray photons, while smaller atoms do not and the X-rays pass right through. For instance, the soft tissue in the body is composed of smaller atoms, so it doesn't absorb X-rays very well, but calcium atoms in the bones are much larger and do absorb X-rays. A camera on the other side of the patient records the patterns of X-ray light passing through the patient's body. In a CT scan, a series of X-ray beams is directed through the body from different angles. This creates cross-sections so scientists can get a better view of the body. The images are put together by computer into a stack of pictures that can be viewed rapidly, like flipping through a deck of cards.
The American Association of Physicists in Medicine contributed to the information contained in the TV portion of this report.