While cardiovascular disease remains a major killer around the world (India alone accounts for nearly 40 million people diagnosed with heart disease) doctors are better equipped than ever to battle it thanks to breakthroughs in prevention, diagnosis and treatment. In fact, 70% of the drop in heart disease deaths over the past decade has come from innovations such as clot-busting drugs and bypass surgery. Given below are some of the most promising new medications, diagnostic methods and surgical techniques on the horizon.
A NEW BLOOD TEST IDENTIFIED HIGH-RISK CANDIDATES
Many people start down the road towards heart disease and do not even know it. Some suddenly gain weight around their midsection in their late 40s. In others blood pressure goes up for the first time. Some people may also silently develop insulin resistance, a precursor to diabetes and a contributor to the growth of artery-clogging plaque. A new blood test may help identify these candidates before they suffer permanent heart damage.
The test looks at the level of binding protein which is lower in people who do not process insulin properly.
In studies, When insulin-resistant women were given a drug that lowered blood sugar and put on a special diet, their blood pressure and insulin levels came down, the BP-1 marker their risk factors. Researchers believe that the BP-1 test could be available within five years.
BETTER CHOLESTEROL CONTROL
About a third of those who are had one heart attack will suffer another, so staving off will the second crisis is critical. A 1996 study found that people who had high cholesterol levels could prevent artery damage and cut their chances of a second attack or a stroke almost in half by taking cholesterol-lowering drug called statins.
Experts believe that such preventive drug therapy works best in those who have other risk factors such as hypertension or diabetes. In those who only have mildly elevated cholesterol, but no other risk factors, just a low fat diet and an exercise regimen coupled with regular monitoring can greatly reduce their risk of a further attack.
CAN ANTIBIOTICS STOP HEART DISEASE?
Many researchers believe that coronary artery disease develops when inflammation in blood vessel walls promotes the growth of plaque. Now some scientists think that herpes viruses such as cytomegalovirus, a cousin of the virus responsible for cold sores, or the bacterium Chlamydia pneumoniae, which causes respiratory infections, may trigger the initial inflammation.
There plenty of circumstantial evidence. Both organisms have been found in arterial plaque, say epidemiologists at the University of Washington School of Public Health in Seattle. A 1996 study conducted at the National Heart, Lung, and Blood Institute found that people who had CMV infections were 10 times as likely to have plaque grow back after it was cut away. And heart patients are likelier than others to have antibodies to C. pneumoniae in their blood.
If bacteria promote clogged arteries, then antibiotics might slow the process. Scientists are planning a study to test that idea, giving antibiotics to people who have had one heart attack to try to prevent a second one. As for the viral threat, vaccines could prevent infection in the first place, but shots are still several years away.
A HEART Mammogram
Almost two-third of those who die suddenly of coronary disease have had no previous symptoms. Fortunately doctors now have a way to detect early signs of clogged arteries while there still time to intervene. Electron-beam computed tomography, better known as Ultrafast CT, has been dubbed a mammogram of the heart, because it picks up tiny calcium deposits in arteries, just as X-ray detect calcifications in breast tissue.
Among the potential uses for Ultrafast CT are determining whether heart attack candidates, for eg.,postmenopausal women, with average cholesterol levels might benefit from cholesterol-lowering drugs or estrogen therapy.
A MENTAL STRESS TEST
Exercise stress tests are notoriously bad at diagnosing heart disease in most people. Nor can they measure the effects of mental stress, which strains the entire cardiovascular system. Now researchers at Duke University Medical Center in Durham, N.C. have come up with a test to do just that.
Patients with heart disease were asked to give a speech, trace the outline of a star from its reflection in a mirror, and do complex math problems quickly all while researchers measured heart function. Two-thirds of the 126 patients studied showed cardiac abnoralities during both types of test. But those who turned up positive on the mental test were three times as likely to suffer a heart attack or need surgery in the next five years.
Mental stress tests not replace exercise tests, but they could become a valuable added diagnostic tool.
A MORE ACCURATE EXAM FOR WOMEN
When a treadmill test turns up symptoms of heart disease, the next step is often a thallium test. The radioactive element is injected into the body, allowing special cameras to trace blood flow to the heart muscle. There one catch: In women, breast tissue often casts a shadow that can prompt a false diagnosis of ischemia (inadequate supply of blood to the heart). Cardiologists are increasingly turning to a technology that does not pose this problem; positron emission tomography scans.
PET uses elements such as rubidium, which are less prone to image distortion. It has therefore become the definitive test in women because it is more accurate and gives more detailed information. PET scan not only eliminates interference from breast tissue, but it can also better detect mild blockages, which my not produce symptoms in women. PET also takes only about an hour, compared with four or five hours for a thallium test.
A BLOOD TEST DETECTS HEART ATTACK
Even the most advances diagnostic technology is of little help when a man enters the emergency room with chest pain: Roughly one-third of the time, a heart attack does not show up on the ECG. But a new blood test can swiftly reveal if even a mild heart attack has occurred.
The test measures blood levels of cardiac troponin I, a protein released only by a damaged heart. In a 1966 study of more than 1,400 people by the Brigham and Women Hospital in Boston, researchers reported that 25% of patients with chest pain who might normally have been diagnosed with unstable angina (chest pain that is not immediately fatal) had elevated levels of protein, indicating they actually had mild heart attacks. The blood test allows researchers to quickly rule out or confirm a heart attack when other tests are in doubt, or to classify a patient as high risk.
TINY TOOLS, GENTLER SURGERY
Its called minimally invasive heart surgery, and some say it is the biggest advance in cardiac surgery in the last quarter century. Traditional bypass surgery involves sawing through the breastbone and prying open the rib cage, leaving a foot-long scar. Doctors practicing the new technique insert miniature surgical tools through small incisions in the chest, leaving only small scars.
The most widely used method, the Heart port Port-Access system, cuts the hospital stay in half, and recovery time to two to three weeks, compared with 12 weeks for open-chest surgery. A patients bill slightly lower than the one for a conventional bypass.
Because the technique is relatively new, long-term follow up results have not yet been published. Ultimately, though, half of those who undergo bypass surgery each year might be candidates for minimally invasive surgery.
LASERS SAVE HOPELESS CASES
When clogged arteries starve the heart of blood and oxygen over a long period, angina becomes chronic and the heart muscle can be seriously damaged. For people who are not helped by angioplasty or bypass, a technique called TMR can buy time.
The idea was inspired by snakes and alligators, whose heart soak up oxygen-rich blood like a sponge because they have dozens of little channels running into the heart muscle. TMR uses a laser to create 15 to 50 such channels in the human heart. When the heart contracts, blood is squeezed through the new channels into the heart muscle. In a few weeks, the channels branch out and new blood vessels grow. Although the procedure is not curative, most patients have significant angina relief.
KEEPING TIRED HEARTS TICKING
If a weakened heart can not pump fast enough to keep the body going, congestive heart failure develops. When medication does not help, the next step is a transplant. Each year less than one percent of those who need a donor heart actually get one; many die waiting. In the past few years, doctors have begun to use battery-powered implants called left ventricular assist devices to keep worn-out hearts pumping.
After the L-Vad, a bit larger than a mans fist, is implanted beneath the diaphragm, patients go home and can resume normal activities. In some patients the heart may even regain strength, and not need a transplant at all.
Researchers are now conducting a clinical trial in 130 patients to see if L-VADs could be used permanently. They are also developing smaller models that fit women more comfortably. Although the device is not any cheaper or better than a transplant, given the scarcity of donor hearts, L-VADs can meet the shortfall.
THE WONDER DRUG
If it were half as effective, 10 times as expensive, and on prescription, maybe more people would take it seriously, lamented Dr. Charles Hennekens, Professor at Harvard Medical School. He was talking about aspirin, the world largest-selling drug, that has precious little hype built around it because it is so freely and cheaply available.
Yet doctors are now looking at aspirin as the 20th century wonder drug, one which does not just get rid of headaches and fevers, but also helps reduce chances of heart attacks and strokes, alleviates the pain of arthritis and is even being considered as a new line of defence against HIV.
HOW IT WORKS
The key compound in aspirin is salicin, found in the bark of the willow tree. Folk medicine has used it to treat all kinds of aches, pains, fevers and swellings. Clay tablets from the sumerian period describe the use of willow leaves to treat rheumatism and the Egyptians, used them too. Around 400 BC, Hippocrates used a brew of willow leaves to ease the pain of childbirth.
Aspirin was first marketed mainly as an anti-inflammatory drug, particularly for people suffering from rheumatism, but its popularity as a general purpose painkiller followed quickly.
The discovery, in 1971, of how aspirin actually works has led to its use in a number of new applications. The British pharmacologist and Nobel Prize awardee, Sir John Vane, showed that aspirin worked by suppressing the production of local hormones known as prostoglandins. Among other things, prostoglandins increase the sensitivity of pain receptors on nerve endings and dilate blood vessels.
Prostoglandins are found in most tissues of the body and they have a number of different functions, including regulating the contraction of the so-called smooth muscle that is found in the blood vessels, the stomach, the intestines and the bladder. But they also regulate the aggregation of platelets. Suppress the prostoglandins in platelets, therefore, and you suppress the formation of the sort of clots that trigger heart attacks and strokes.
Prostoglandins are released when cells are injured and trigger the typical symptoms of inflammation, including swelling and pain. This discovery confirmed why aspirin had been so effective in treating arthritis it eases the pain, controls the inflammation; and reduces fever which frequently plagues people with rheumatoid arthritis.
THE WORLD FIRST SYNTHETIC DRUG
When aspirin was invented on August 10, 1897, it become the world first truly synthetic drug and paved the way for the modern pharmaceuticals industry.
The newly-discovered drug become the first drug ever to be tested in clinical trials before registration. It was entered in the Patent Office at Berlin on February 1, 1899, under the trade name aspirin. The letter a stood for acetyl and spir was derived from spirea acid, which is chemically identical to salicylic acid. This was obtained from the sap of the plant, Spirea ulmaria, a shrub belonging to the rose family which usually grows abundantly in wet areas.
Over 40,000 tonnes of aspirin are consumed globally every year. In India, around 3,000 tonnes of aspirin is sold annually.