Little-used scan can find hidden heart disease
The former president has chest pains. A catheter threaded through his heart finds all three major arteries and a tributary up to 90% blocked. Surgeons buzz through his chest with an electric saw, stop his heart for 73 minutes and use veins from his leg and elsewhere to bypass the blockages.
Bill Clinton is saved. But some cardiologists say the event was far from a medical triumph. As soon as word got out about the extent of previously undetected clogs in Clinton’s arteries, some of the nation’s top cardiologists began trading barbed e-mails and phone calls, decrying the event as the ultimate failure in preventive medicine, even as “unconscionable.”
“The bottom line is, Bill Clinton’s walking into the hospital with chest pains is a shocking event in a country where we have plenty of tools to prevent that,” says Dr. Morteza Naghavi, a Houston researcher who founded the Assn. for the Eradication of Heart Attack, an influential group of cardiologists that advocates an overhaul of how patients are assessed for heart disease.
As it is now, about 88% of those who have heart attacks would have been labeled low to moderate risk by their doctors on the previous day, according to a recent study published in the Journal of the American College of Cardiology.
Clinton’s experience demonstrates that even a former president with access to the best medical care available can have undiagnosed heart disease. Doctors like Naghavi advocate aggressive use of preventive screening, such as blood marker tests and noninvasive scans. In particular, some cardiologists are promoting wider use of a noninvasive diagnostic test known as the coronary calcium scan.
But other physicians say some of these tests have not proved their value, and they cite the expense of widespread screening programs in a time of rising medical costs.
About 1.5 million Americans this year will not be as lucky as Clinton was. They won’t get a warning sign -- allowing time to get to a hospital -- before they suffer a heart attack. About half of those will die.
Clinton appears to have never had the simple $250-to-$400 diagnostic scan that the eradication association and others advocate, although Walter Reed Army Medical Center, near the White House, has been using such tests in middle-aged Army personnel for years, after finding that traditional treadmill stress tests failed to identify many future heart attack victims.
The scan, known as an electron beam computed tomograph, or EBCT, probably would have detected the extensive plaque that lined Clinton’s coronary arteries, some cardiologists said. Aggressive interventions, such as stents that open the blockages, could have been taken long before emergency bypass surgery was necessary. Even if the measures couldn’t have averted open heart surgery, doctors would have been prepared, rather than surprised, to find such threatening problems.
Some physicians are skeptical of the scans, however. “There’s cost and there’s radiation, and we don’t know how much information it adds beyond traditional indications,” says Dr. Lori Mosca, director of preventive cardiology at New York-Presbyterian Hospital.
She notes that the National Institutes of Health are sponsoring national trials ending in 2008 that may show whether the test actually changed the fates of those who were determined to be at high risk.
Many cardiologists have complained that the scan isn’t recommended to more Americans now. That is changing slowly as the evidence supporting the benefits of the test becomes more convincing and more medical organizations endorse its use. Earlier this year, three studies published in leading medical journals, including the Journal of the American Medical Assn., found the scans to be of benefit in detecting heart attack risk.
Dr. Scott Grundy, a University of Texas Southwestern researcher who drafted guidelines for the use of statin drugs for the National Cholesterol Education Program, says he believes the scans are as important as cholesterol tests in determing heart attack risk.
Groups such as Naghavi’s recommend that men older than 45 and women older than 55 should have the scan, regardless of whether they have risk factors such as diabetes, sedentary lifestyle, obesity, smoking or kidney disease.
The American Heart Assn. is considering a less radical proposal, suggesting that cardiologists scan only people in those age groups who have traditional risk factors. About 40% of Americans in that age group have some or all of those risk factors, putting them in what is known as the “intermediate risk” category.
Most insurers do not presently reimburse for the scan because they consider the technology to be “investigational.” A spokesman for WellPoint Health Networks, the nation’s second-largest health insurer, said the company was considering covering the test. Some cardiologists say insurers should pay for the test because its wider use would save lives. “It’s a tragedy because the insurers cover colonoscopy and mammograms, and yet most won’t pay for a test for a disease that kills a million men and women a year,” says Dr. P.K. Shah, director of cardiology at Cedars-Sinai Medical Center in Los Angeles. More than 45,000 women die of breast cancer each year, for example; heart disease kills 10 times as many women.
EBCT scans, which have been conducted for 20 years, take fast pictures of the heart for 20 seconds inside an open machine. Some critics cite radiation exposure risks, but proponents say it’s relatively small -- about equivalent to a set of dental X-rays. (Good-quality scanning can also be done with newer CT scanning equipment that many hospitals have, although it produces two to five times the amount of radiation depending on the machine model.)
The medical center run by Dr. Kenneth Cooper, a Texas physician who prescribed an EBCT scan for President Bush, has scanned 10,000 patients who had never had chest pains or other symptoms of heart disease, and it followed them for five years as part of the national trials. Though 60% of those patients were considered to be at intermediate risk, just 278 had heart attacks, and most of them had calcium scores of more than 331 (300 is considered very high). “The correlation was striking,” Cooper said.
A high calcium score, Cooper says, does not mean you are certain to suffer a heart attack -- as long as you do something about it. When his late mother-in-law, who had already suffered a heart attack, had the test, her score was an extremely high 6,000. But she lived to age 92. “I can assure you if her daughter hadn’t been married to me, she would have died 20 years ago,” Cooper jokes.
Alan Gehm, 53, was having some chest discomfort and couldn’t get an appointment with any cardiologists in the San Diego area, where he lives. So he went to Harbor-UCLA in Torrance, where the scan found a score of 1,000. The next step: another test on the same machine, this time using dye injected into the arm to give a better picture of blood flow. This EBCT angiogram (which insurers do cover) turned up a substantial blockage. The next day doctors put a stent in his artery. “It’s a good system,” Gehm says. “It saved my life.”
The scan has been shown to accurately rule out the 99.5% of those who will not have a heart attack or stroke in the next four to five years, even if they have other risk factors. If the test shows few or no calcium deposits in someone with chest pains -- and if no blocks are found on the EBCT angiogram -- physicians can generally avoid doing the far more common type of invasive and risky diagnostic angiogram, covered by insurance, that Clinton needed before his bypass.
“I can’t tell you the tens of thousands of unnecessary angiograms that are done every year,” says Dr. Harvey Hecht, director of preventive cardiology at Beth Israel Hospital in New York. At least 20% of the angiograms performed each year reveal no evidence of obstructions; one study of 9,238 angiograms from five community hospitals reported that 40% showed no obstructions.
In addition to a cholesterol test, the Heart Attack Eradication group advises people to have a C-reactive protein test, which determines inflammation in the blood, and which some scientists believe is also a factor in determining heart attack risk.
Naghavi’s group and some other preventive cardiologists also recommend moving away from use of the electrocardiograph -- a still widely used test that monitors the electrical pulses in the heart. Naghavi and others say the test only indicates whether damage has already been done to the heart, rather than predicting its onset.
“We grew up with the EKG; that’s the textbook cardiology,” says Naghavi. “We think that is old cardiology. It refers to the attitude that you wait and see the disease and treat the disease. That’s outdated, and unfortunately it’s practiced everywhere.”
Treadmill stress tests, which involve attaching an electrocardiograph to the body, typically miss more potential heart attack victims than they identify, giving many people a false sense that they’re healthy, some doctors say. This is why major cardiology groups do not suggest doing them on patients without symptoms, though they are widely performed. Clinton had treadmill stress tests done annually.
As for Clinton’s case, the former president’s spokespeople declined to comment, referring a reporter to transcripts of news conferences and a “Larry King Live” interview given by cardiologists at New York Presbyterian Hospital, where the bypass was performed. Dr. Allan Schwartz, the hospital’s chief cardiologist, was asked whether Clinton should have had a coronary scan.
“Whether it would have been useful in detecting things earlier in the president, I can’t answer,” Schwartz said. “But again, this was detected at the right time.... The key thing here is that his heart had suffered no damage and has suffered no damage.”
Some advocates say doctors have been reluctant to embrace the technology because of its association with entrepreneurs who have bought the million-dollar-plus machines and offered the scans at shopping malls. Says Dr. Matthew Budoff, a Harbor-UCLA Medical Center cardiologist and an advocate of the scans, “If they didn’t learn it in training or medical school, it’s less likely to become part of their practice.”