Key to performing both CTA and CTP is use of the 320 computed tomography scanner, the most advanced technology available to image the heart and its surrounding blood vessels. The device was first installed in North America at Johns Hopkins in 2007 and can produce three-D images of blood vessels no bigger than the average width of a toothpick (1.5 millimeters). Results from both 320-CT tests will be compared to those from SPECT and what is found by cardiac catheterization.
"Perfusion imaging is a simple and easy test for patients to undergo," says Lima, who adds that the whole procedure usually takes less than 20 minutes to set up and perform. Cardiac catheterization, which also checks for heart vessel blockages, takes longer, between 30 minutes and 45 minutes to perform, and requires several hours for recovery. Potential complications from the invasive procedure, although rare, include heart attack, stroke and death.
"If we can more easily examine patients, then we can reduce the amount of time needed in hospital and, we hope, reduce the number of invasive procedures, which are more inconvenient and open to greater risk to patients from complications," says Lima, a professor of medicine and radiology at the Johns Hopkins University School of Medicine and its Heart and Vascular Institute.
More than a quarter-million Americans undergo coronary bypass surgery each year, and another 1.2 million people undergo angioplasty, a procedure much like catheterization that forcibly opens narrowed arteries.
Lead study investigator and cardiologist Richard George, M.D., part of the Johns Hopkins team that developed special computer software to accurately measure the speed of blood flowing through the heart's arteries and m
|Contact: David March|
Johns Hopkins Medical Institutions