The 'gold standard' of detecting coronary disease is, of course, angiography, where a cardiac catheter is inserted through the patient's groin and subsequently an iodine-based dye is injected into the coronary arteries. This gives a road map of the obstructions. But angiography is an invasive method.

Scientists looking for a reliable and non-invasive diagnostic tool have long been eyeing the machines that are routinely used to detect wounds or warts in static organs, like the Computerised Tomography (CT) Scan and the Magnetic Resonance Imaging (MRI) machine. These MRI machines, however accurate, are nevertheless too slow for the heart, like a pinhole camera trying to capture a cricket ball in flight.

Now, the scene is totally revolutionised with the advancement of technology. GE Medical System has devised a unique combination of a cardiovascular MRI and a fast CT scan, both geared to take high-speed sectional images of the heart. This combination, worth close to $3 million (Rs 13.2 crore), is installed in just about a dozen centres in the world, including the National Institute of Heart, Bethesda, US, Stanford University and Keio University in Japan. Escorts Heart, Institute and Research Centre (EHIRC) in Delhi is one of the centres to acquire the machine that may dramatically alter the detection of early symptoms of coronary vascular disorder.

Generally, patients wake up to the problem of clogged coronary vessels only after 70 percent of one of the arteries is choked. By the time the first stab of chest pain is felt, caused by insufficient blood supply to the heart muscle, or ischaemia, one or two coronary vessels may have narrowed by half or more. However, cardiovascular MRI, with the facility to present three-dimensional data, is capable of picking up a 'stenosis', or the narrowing of a vessel, when it has just hit the 10 percent mark.

From the highly magnetised MRI chamber, the action shifts to the fast CT scan tunnel. There, the machine takes fast counts of calcium in and around the heart; more calcium meaning more chance of a plaque buildup. While a normal CT scan takes stationary calcium profiles, the cardiac variety slices up coaxial frames, at the rate of 10 frames in a single cardiac cycle of 0.8 second. The CT scan would show the presence of calcium even at the 20-30 percent stage.
The benefit of an early diagnosis of the hardening of a coronary artery is that it can be reversed by making some changes in one's lifestyle. Certainly, changing one's lifestyle is a highly affordable insurance against the cost, anxiety and agony of an open-heart surgery, which may occur later in life.