Cover Story
A Change of Heart
Story by Jeanne Mettner | Illustration by John Karapelou
As cardiovascular care has evolved, so have the roles of the physicians who treat heart patients.
In 1977, nine years after the first coronary artery bypass was performed, a German radiologist caught the attention of the medical community and the public by inserting a catheter into a patient’s obstructed blood vessel, then blowing up a balloon. Researchers in the United States and Europe later designed a metal mesh tube called a stent that could prop open the walls of vessels. By 2003, stents were being coated with drugs that could help stave off the threat posed by scarring in the arteries. Within 40 years, cardiologists had a full arsenal of treatments that could restore blood flow in the most occluded arteries and the keep the sickest hearts pumping.
For the most part, these innovations have been good for patients. But for better or worse, they have irrevocably altered what heart specialists do. In the early 1980s, a cardiologist who saw a patient with angina caused by coronary artery disease would make a diagnosis and send that person to a cardiac surgeon for a coronary artery bypass graft (CABG). By the late 1980s, cardiologists were doing balloon angioplasties in catheterization labs to open occluded vessels, while cardiac surgeons stood by in case the procedure failed and emergency bypass surgery was needed. Today, the surgeon might not need to stand by at all, as cardiologists often keep patients in their care, recommending lifestyle changes, prescribing lipid-lowering or anti-hypertension medications to keep myocardial infarctions at bay, and even doing percutaneous interventions in the cath lab following angiography. Once diagnostic collaborators, cardiologists have become cardiac surgeons’ chief competitors.
Understandably, cardiology’s foray into minimally invasive heart procedures has changed the relationship between heart surgeons and cardiologists. “It varies from institution to institution, region to region. But, in general, cardiologists feel that they are the gatekeepers, and they control the decision,” says Vibhu Kshettry, M.D., a senior cardiac surgeon and co-chair of the Complex Cardiac Disorders Program at Abbott Northwestern Hospital’s Minneapolis Heart Institute. “That can sometimes put a strain on a professional relationship, sure; but more importantly, it puts a strain on resources and on patient care.” Kshettry explains that some patients who undergo percutaneous coronary interventions may be better candidates for bypass surgery but aren’t told about the benefits or given the option. “Eventually, that patient may come in for surgical intervention, which costs everyone more money and time.”
A Specialty in Flux
If there is any uncertainty about the degree to which interventional cardiology has changed the practice of cardiac surgery, one need only look at the statistics. In 2001, 516,000 CABGs were performed in the United States. By 2006, that number had dipped to 330,669. The U.S. Cardiac Surgery Devices Market division of Frost & Sullivan, a business and research consulting firm, estimates that just five years from now only about 223,000 bypass operations will be done annually. At the same time, data from the Agency for Healthcare Research and Quality show that while the number of coronary artery bypass procedures declined by 28 percent between 1997 and 2004, percutaneous coronary interventions increased by 36 percent.
“This shift has been driven by patients who are clearly asking for the less-invasive procedure, and who can really blame them?” says Tim Henry, M.D., an interventional cardiologist at the Minneapolis Heart Institute. “People aren’t wanting an operation that costs five to 10 times more [than angioplasty] and puts them in the hospital for five to seven days, particularly when they know they can get a procedure where they are home in less than 24 hours and back to work in a week.”
The numbers appear to be registering with future physicians, who are increasingly opting not to go into cardiovascular surgery. In 2006, only 84 of 126 available fellowships in cardiothoracic surgery were filled, a stark contrast from 1995, when 200 applicants competed for those slots.
One reason they are not choosing the specialty is because it is not as lucrative as it once was. “For reasons not entirely clear, Medicare reimbursement for a three-vessel coronary bypass is probably 50 percent of what it was 10 years ago,” says Herbert Ward, M.D., C. Walton and Richard C. Lillehei professor and chief of cardiovascular surgery at the University of Minnesota. “Since all the insurance companies use Medicare as a benchmark for gauging their own reimbursement levels, surgeons are getting fewer dollars across the board for each case of cardiac bypass surgery they do.” And that has taken a toll on cardiac surgeons’ salaries. “A lot of cardiac surgeons have seen their income drop dramatically because of fewer patients or sicker patients who take longer to work through the system and lower reimbursement rates for each patient,” says Michael Thurmes, M.D., an interventional cardiologist and president of the Minnesota Heart Clinic at Fairview Southdale Hospital.
Another is the amount of training required. Both cardiology and cardiac surgery require fellowships on top of residencies. For an incoming medical student, that can translate to 10 years or more of training, during which they must start repaying their student loans, before starting practice. Some are less willing to pay that kind of a price—and incur the debt associated with it—when the subspecialty is seeing the number of surgeries and the reimbursement for those procedures declining and when job opportunities aren’t as plentiful as they once were. A study of cardiothoracic surgery residents published in the September 2006 Annals of Thoracic Surgery found 12 percent of those who were seeking jobs in 2004 received no offers. Given those disincentives, it’s not surprising that 23 percent of the 88 residents who responded to the survey said they would not choose a career in cardiothoracic surgery again, and 52 percent said they “would not strongly recommend cardiothoracic surgery to potential trainees.”
Retirements are also affecting the field. In 2002, the Society of Thoracic Surgeons noted that more than half of U.S. heart and lung surgeons indicated that they plan to retire between 2012 and 2015. In addition, an American Medical Association study of active physicians in 35 specialties found that thoracic surgery was the only one to see a decline in numbers between 1995 and 2004. Slowly, an older generation of cardiovascular surgeons is leaving the field and not being replaced.
Treatment Milestones
1967
Cleveland Clinic’s Rene Favaloro, a cardiac surgeon from Argentina, performs the world’s first saphenous vein coronary artery bypass graft surgery.
1977
German radiologist Andreas Gruentzig performs the first percutaneous transluminal coronary angioplasty for the treatment of angina pectoris in Zurich, Switzerland.
1978
Americans Richard Myler (San Francisco) and Simon Stertzer (New York) perform the first angioplasty in the United States.
1986
In Toulouse, France, Jacques Puel and Ulrich Sigwart insert the first bare-metal stent into a human coronary artery.
1987
Lovastatin becomes the first lipid-lowering statin agent to be approved by the FDA.
1994
The FDA approves the first bare-metal stent for use in the United States.
2002
The first drug-loaded stent is implanted in a patient in Europe.
2003
The FDA approves the first drug-loaded stent for use in the United States.
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As a result, the Society of Thoracic Surgeons has actually predicted a manpower shortage in the next five to seven years, according to Kshettry, who notes that the patient load of cardiothoracic surgeons includes those needing valve repairs and replacements, and those with congenital defects, heart failure, aortic aneurysms, and benign and malignant lung and other thoracic diseases, in addition to those needing cardiac bypass surgery. Because of the aging of the population, he says, the number of valve surgeries has increased 25 percent in the last five years.
Kshettry also points out that the demise of coronary bypass surgery predicted years ago when drug-eluting stents came on the scene has not happened because of the increased number of patients with severe multi-vessel coronary artery disease who are not candidates for stents and the need for restenosis among patients who have stents. “Patients will continue to need cardiac surgical procedures for the next many decades,” he insists. “If there are not trained surgeons, how will we provide care to our patients?”
A Field in Blossom
Where enthusiasm for cardiac surgery has waned in the eyes of some trainees, interest in cardiology has blossomed. Even in the early 1980s, as the number of bypass surgeries was skyrocketing, cardiology was growing—in part because every bypass required a cardiologist to do an angiogram to map out a surgical approach. By the mid-1980s, percutaneous coronary interventions such as angioplasty were gaining ground, and medical schools were touting new cardiovascular subspecialties such as preventive cardiology, interventional cardiology, and cardiac electrophysiology. By 1997, stenting was being done in hospitals across the country, and by 2004, U.S. cardiologists were performing close to 1.3 million angioplasties a year.
This shift has prompted some cardiac surgeons to learn new interventional techniques in order to expand their offerings. Kshettry, for example, has learned several percutaneous procedures, including aortic stent grafting. In addition, he says, cardiac surgery residents and fellows are being trained in angioplasty and other procedures done in the cath lab.
Joe Babb, M.D., an interventional cardiologist and past president of the Society for Cardiovascular Angiography and Interventions, attributes the decline in the number of bypass surgeries to the increase in percutaneous techniques. “We are now, because of technology and better devices and pharmaceuticals, able to do things that not all that long ago were totally the province of cardiac surgeons, and we can do them with safety and durability.”
That has led to the growth of interventional cardiology training programs. According to Accreditation Council for Graduate Medical Education data, the number of programs has increased from 115 in the 2003-2004 academic year to 130 in the 2007-2008 year. The number of approved training slots in those programs has risen from 273 to 294. Applicants continue to outnumber funded positions. Babb says in some instances, training directors have had to turn away qualified applicants because they didn’t have the money to pay them.
However, interest in interventional cardiology has and is expected to grow, despite the fact that Medicare reimbursement for percutaneous procedures has fallen (Babb says today he would be paid about one-quarter of what he received in the mid-1980s for doing a balloon angioplasty). At East Carolina University’s Brody School of Medicine in Greenville, North Carolina, where Babb directs the interventional cardiology training program, the two fellows who graduate each year have readily found jobs. Those subspecialists have also seen salaries increase. A survey by the American Medical Group Association (AMGA) found that annual compensation for invasive cardiologists increased by 29 percent from $286,000 in 2000 to $369,000 in 2003. A 2004 study by the Medical Group Management Association found that invasive cardiologists’ median income rose 21 percent from $340,000 in 1999 to $410,000 in 2003.
Babb predicts interventional cardiologists will be in demand well into the future. “They have improved imaging techniques that help identify people at substantial risk, and if you know that the patient has well-defined high-risk features from a stress-imaging study and that the artery is fixable, then you can intervene on those people and strike preemptively, as opposed to waiting until they present with an acute event such as a heart attack. The decision to do this, however, must be very carefully thought out and not just applied to every patient with a stress-test abnormality,” he says. Coupled with that is the fact that the obesity epidemic is likely to increase the prevalence of heart disease. “We have an enormous reservoir of disease out there,” Babb says. “I hate to put it this way, but all physicians caring for cardiovascular patients have a lot of job security.”
Black and White... and Gray All Over
Most cardiovascular surgeons and cardiologists follow these guidelines when recommending coronary artery bypass over percutaneous interventions:
Coronary artery bypass grafting surgery should be used to treat significant blockages (greater than 70 percent) in the left main coronary artery, coronary disease that causes impaired ventricular function and affects three or more vessels, people with diabetes who have disease in three or more vessels, and coronary artery disease characterized by a tight proximal left anterior descending artery. Angioplasty or stenting should be used to treat patients with coronary artery disease in one vessel.
Beyond such black-and-white scenarios lies a massive gray area where decisions are made based on patient preference, the skills of the surgeon or cardiologist, the patient’s age and health status, and myriad other factors. More and more, cardiologists are treating disease involving two or more vessels with stents, even though the Food and Drug Administration considers it to be an “off-label” indication for the therapy. Different surgical programs in the Twin Cities, for example, report a fairly wide variation in the percentage of people sent to surgery. Says Michael Thurmes, M.D., an interventional cardiologist and president of the Minnesota Heart Clinic at Fairview Southdale Hospital: “Patients usually prefer the minimally invasive procedures, and it’s usually easier to do what the patients prefer. There are no standard clinical protocols or algorithms.”—J.M.
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One concern prompted by the rise in percutaneous procedures is whether cardiologists are abusing their role as gatekeepers by inappropriately recommending angioplasty or stenting when a patient might be better off having bypass surgery. “I would argue if the physician doing the decision-making has a vested interest in which treatment option [medication, angioplasty, or bypass surgery] is chosen, he or she will likely choose the one that encompasses his or her specialty,” Ward says. “None of us want to harm the patient, but there are justifications that you can make to yourself that your way is the best way.”
In Minnesota, the structure of group practices bears little incentive for cardiologists to be self-interested or narrow-minded in their referral choices. “If you are at a hospital that has 10 cardiology groups and 10 surgery groups all performing procedures, then things might be different,” Henry says, adding that such scenarios are common on the East Coast. “But in this state, most hospitals are set up to have single-specialty groups at a single hospital, so cardiac surgeons and cardiologists are essentially on the same team. Surgeons are in the cath lab reviewing films with us all the time. They never look at me and say, I am just trying to make money or vice versa. I honestly can’t think of one case where a surgeon has said I should not have done an angioplasty.”
Some cardiologists, however, do allow that the situation might be different today if surgeons had had more say in directing patient care. “One can imagine that if the surgeons were gatekeepers to heart care, there may have been a slightly different twist to how things turned out,” Thurmes says. “The surgeons would favor surgery more often than cardiologists do now. Stents would have arrived, but they probably wouldn’t have advanced as much.”
Interventions on Trial
Although cardiologists and cardiac surgeons may disagree about who should be making decisions about what patients need, a critical question remains: Which treatment—bare-metal stents, drug-coated stents, or CABG—results in better outcomes? The answer, it seems, is still up for grabs.
This is not to say investigators have left the topic untouched. Between 2006 and 2007 alone, hundreds of articles explored the efficacy of bare-metal stents, drug-coated stents, and coronary artery bypass, as compared with each other or with medical therapy. The results are confounding at best.
In May of 2005, for example, the New England Journal of Medicine published a study demonstrating that patients with two or more diseased coronary arteries lived longer if they had bypass surgery than if they received stents. The percentage of patients who required revascularization within three years was significantly (20 percent) higher among those who initially received a stent than those who underwent a bypass.
A meta-analysis by researchers at Stanford University published in the Annals of Internal Medicine in 2007 showed that 10-year survival rates were the same for patients who underwent percutaneous interventions as for those who had CABG, but five years out, the absolute rates for repeat procedures were a full 30 percentage points higher in the stent group than in the bypass group (40.1 percent versus 9.8 percent). Of the 23 randomized controlled trials that the authors analyzed, only one included drug-loading stents. They also found the incidence of stroke to be higher in patients who had bypass surgery than in those who had undergone angioplasty.
In the COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial, researchers found that that among patients who had predictable, nonprogressive chest pain (or stable angina), those who underwent angioplasty and received stents reported fewer episodes of angina during the first two years following treatment compared with those who received medications alone. Within five years, the frequency of angina was nearly identical between the two groups.
The pace of conducting clinical trials may, in part, explain the varying conclusions. “The problem with the data [on efficacy and outcomes] is that it takes five years to accumulate it, and by the time the data comes out, it’s always outdated because cardiology is evolving at such an accelerated rate,” Thurmes says. “There are a bunch of studies out there that are complicated and don’t give a straight answer.” For example, some include drug-coated stents in their analysis, others don’t; yet drug-coated stents are widely used today, despite recent controversy over whether they are linked to increases in the rate of death and heart attacks among patients 18 months to three years after receiving them. Others compare percutaneous interventions to medical therapy but not to CABG; often the choice for patients is between angioplasty and CABG, not between angioplasty and drugs. Some studies provide data only on people age 65 and older, making the implications of the findings unclear for younger patients. “There are way too many variables to study and way too many patients to study within those variables, so by the time you have the data to produce the clinical guideline, medicine has changed beneath you like shifting sand,” Thurmes says.
Bob Wilson, M.D., an interventional cardiologist and professor of cardiology at the University of Minnesota, uses a different metaphor to describe the quandary around clinical trials. “Conducting randomized trials is a lot like using a bucket of screws to find out which screwdriver works best,” he says. “If half the bucket is filled with slotted screws and half with Phillips screws, the so-called ‘best-working’ screwdriver will all depend on which screws you select for your sample—not on the actual performance of the tool.” Researchers don’t know, for example, if the majority of a sample population may be genetically predisposed to react favorably to a particular therapy, making it even more difficult to draw conclusions about efficacy and outcomes.
A Collegial Relationship
One would think that with stiff economic competition and contradicting viewpoints on scientific findings, tensions between cardiologists and cardiovascular surgeons would run high. But that does not appear to be the case—at least not anymore, and not in Minnesota, according to Wilson. “I can remember that every night before I would perform an angioplasty in the 1980s, I would get yelled at by a cardiac surgeon,” he says. “I don’t think it was so much that they thought I was taking business away from cardiac surgery because there were not that many angioplasties done back then. I just think they thought it was a crazy idea. But those days have gone, and I think the two specialties are growing together, slowly combining to become one group.”
Ward thinks cardiac surgery and the other cardiac specialties need to work together much more closely. “Many people now believe—and I am one of them—that cardiovascular surgeons, interventional cardiologists, electrophysiologists, general cardiologists, internists, all lie on the spectrum of services that could be labeled ‘cardiovascular disease care,’” he says.
In a few hospitals, cardiologists and cardiac surgeons are working side by side, literally. Abbott Northwestern and the University of Minnesota Medical Center, Fairview have rooms where cardiovascular surgeons and cardiologists perform procedures at the same time, on the same patient. “We know that blockages in the left anterior descending artery are best treated with a bypass using the left internal mammary artery,” Kshettry explains. “During a hybrid procedure for multi-vessel disease, the cardiac surgeon may do a bypass in this region of the heart with minimally invasive techniques and then turn it over to a cardiologist to stent the remaining diseased vessels.”
As for what’s ahead for heart care, cardiologists see dissolvable stents, which free the vessel walls from mesh wire to make subsequent surgeries safer, and percutaneous valves, which would allow them to repair heart valves without opening the chest. Cardiac surgeons are looking toward more robotic-assisted surgeries and more permanent solutions for heart failure including implantable mechanical machines called ventricle assist devices that can help pump blood when a weakened heart cannot.
The two specialties also envision innovations that will cross disciplines. Gene and stem cell therapies will likely advance, healing the cardiovascular system by clearing the vessels of plaque, triggering new blood vessel growth, or regenerating weakened heart muscles.
Such developments could result in the two disciplines coalescing to provide a more streamlined approach to care. “In the next 10 years, we are going to see an integration of cardiovascular surgery and cardiology in up to half of the institutions in the country,” predicts Wilson. “We will all have different roles, but we are all part of that service line, so to speak. If we all think of ourselves that way, there is really not that much to fight about.” MM
Jeanne Mettner is a frequent contributor to Minnesota Medicine.