From:
DukeMed Magazine
Published: July 10, 2008
Updated: Sept. 28, 2010
The "best" treatment may not be what you think.
By Jeni Baker
Hundreds of thousands of Americans are diagnosed each year with coronary artery disease (CAD), a life-threatening narrowing or blockage in any of the four arteries that feed the heart.
The leading cause of death among both women and men, CAD claims some 500,000 lives in the United States each year -- and comprises more than 70 percent of all heart disease mortality.
While some patients experience no symptoms until they suffer a heart attack, coronary disease often causes symptoms such as chest pain (angina), shortness of breath, fatigue, lightheadedness, and nausea, with patients becoming increasingly weak and debilitated as the heart is starved of oxygen.
Untreated, CAD usually means fewer years of life -- and less quality to those years. In general, the more arteries involved, the sicker the patient. People with multi-vessel disease are often scared, confused, and overwhelmed.
Nearly all say that they just want to get it "fixed."
That's where things can get tricky.
So tricky, in fact, that the first annual Thomas Ryan, MD, Duke Heart Center Lecture, held at Duke in late 2007, was dedicated to debating this important issue.
Entitled "Multi-Vessel Coronary Disease: PCI, Surgery, or Maybe Both Are Wrong?," the event began with the presentation of a case study by moderator Mark F. Newman, MD, chair of anesthesiology.
Newman reported the particulars of patient "Mr. G," as well as his angiogram results, which revealed coronary disease in three arteries.
The case was then discussed by Peter K. Smith, MD, chief of the Division of Cardiovascular and Thoracic Surgery, and Robert M. Califf, MD, and E. Magnus Ohman, MD, both of the Division of Cardiology.
Each spoke primarily in favor of a different intervention for patients who, like Mr. G, suffer from multi-vessel disease, their positions reflecting the larger ongoing debate within the medical community.
Those interventions fall under three main categories:
DukeMed Magazine asked Smith, Califf, and Ohman to recap their remarks on this controversial topic.
PCIs are aggressive, non-surgical procedures used to clear narrowed or blocked coronary arteries.
These minimally invasive procedures include angioplasty -- in which a balloon-tipped catheter is inserted into a blocked coronary artery and then inflated to clear the vessel of debris -- and the placement of stents, minuscule mesh-like tubes that hold arteries open.
The two procedures are commonly performed together.
The immediate risks of complications and infection associated with PCI are significantly lower than those of open surgery.
There's less post-procedure pain, recovery is quicker, and the risk of cognitive decline sometimes associated with CABG surgery is eliminated.
The preferred intervention for people in the midst of heart attacks, PCI gets blood flowing to the heart within 90 minutes, as opposed to the approximately three hours it takes with surgery.
PCI -- in particular, stenting (also known as percutaneous transluminal coronary angioplasty, or PTCA) -- has also been widely criticized.
Plagued by safety and efficacy concerns, stenting has been the topic of an ongoing debate comparing bare-metal stents (BMS) to drug-eluting stents (DES).
BMS have seen a high rate of in-stent restenosis -- plaque buildup inside a stent, which renders it useless.
DES, developed to remedy this issue, were viewed as a great advance. But when studies(1) showed an increased risk of DES-related heart attacks due to in-stent thrombosis (a blood clot that develops inside the stent), many physicians went back to BMS.
Recent findings may cause them to reconsider -- again.
A study(2) of the National Heart, Lung, and Blood Institute Dynamic Registry examined the data of 1,460 DES patients and 1,763 BMS patients one year after their stent placements.
DES patients had a 15.5 percent risk of suffering a major cardiac event compared to BMS patients' 20.9 percent.
In addition, DES patients had a 43 percent less chance of needing post-stent angioplasty or bypass surgery than those with BMS. And the rate of in-stent thrombosis among DES patients was only 1 percent -- down from previous studies. A study(3) of a Massachusetts registry of 21,024 patients had similar findings two years post-stenting.
"PCI has evolved a lot and continues to evolve -- from standard balloon angioplasty to BMS to DES and now to newer forms of DES," says Ohman, who specializes in performing PCI and leads the Duke Heart Center's Program for Advanced Coronary Disease.
"It provides a new way forward for patients -- especially older patients and those with more complex disease -- by lowering the risk of recurrence and offering a tremendous reprieve from their symptoms."
PCI isn't for everyone, but for many patients, it's "a great option that's associated with fewer symptoms and a higher quality of life," Ohman says.
"When a patient is a candidate for both PCI and bypass surgery, I think it makes sense to offer the less invasive PCI as the first line of defense."
Smith, the surgeon, agrees that because PCI isn't as physically traumatic for patients as bypass surgery, it's sometimes the better option for patients who may not be well enough to survive surgery -- such as those with advanced age or prior cardiac surgery, and even some with three-vessel disease.
But, Smith believes, "It's not fair to recommend PCI for a patient and say, 'You can always have surgery later if this doesn't work.' The public gets the idea that surgery and PCI are equivalent -- which isn't true for patients with three-vessel disease, for whom surgery is life-prolonging compared to PCI," he says.
"Proponents of PCI are basically saying, 'We never said it would save anybody's life; we just wanted to improve their symptoms.' And they should acknowledge that this is the case when they discuss options with patients who have life-threatening coronary disease."
So how long must a patient feel better before "improving symptoms" can be called "saving a life"?
The randomized ARTS II trial(4), the largest follow-up study of its kind to compare surgical and PCI patients, looked at 607 patients one year out.
ARTS II showed that "the drug-eluting stent is every bit as good as bypass surgery for treating multi-vessel disease," Ohman says.
Despite the ongoing controversy, PCI continues to be the most commonly used intervention for coronary artery disease.
The American Heart Association (AHA) reports that 1,265,000 PCIs were performed in the United States in 2005 -- approximately two-thirds in men and one-third in women. (Duke cardiologists perform more than 1,300 PCIs every year.)
But while data show that stents have gotten safer, the overall use of angioplasty appears to be waning, according to a recent analysis conducted by the National Cardiovascular Data Registry.
"The rise of angioplasty procedures has leveled off and appears to be on the decline," Duke cardiologist Eric Peterson, MD, told USA Today after reviewing the data.
This could be because some believe that PCI in general is an overused strategy for treating multi-vessel disease that would be more effectively treated with CABG surgery and/or medical management.
A second approach to treating CAD is the coronary artery bypass graft, an open revascularization procedure in which arteries are surgically rerouted to allow unrestricted blood flow around narrow or blocked spots.
Because it entails opening the breastbone, spreading the rib cage, and hooking patients up to a heart-lung machine, CABG is major surgery.
Patients face months of recovery time, a large external scar, and increased risk of stroke.
"The risk of stroke associated with CABG is about 10 times that associated with PCI, and strokes occur very rarely as a result of PCI," Ohman says, adding that most patients fear that CABG will result in neurological complications, as well.
Although many patients opt for PCI to avoid these risks, the AHA reports that approximately 470,000 CABG surgeries were performed in the United States in 2005 -- some 325,000 in men and 145,000 in women.
Duke Heart Center surgeons alone performed over 600 bypass surgeries annually between 2003 and 2007.
Smith says that's because the procedure is tried and true, with proven benefits and very low mortality and complication rates.
"The advantage of surgery is that it's definitive, it's durable, and evidence shows that in almost all cases, it is effective," says Smith, who specializes in performing the procedure.
"CABG completely bypasses the disease, and in many cases, it simply doesn't come back" -- particularly with artery grafting, he adds, although the disease can return with vein grafts.
A 2006 Duke analysis(5) of outcomes from more than 18,000 heart patients found that patients who received bypass surgery lived an average of 5.3 months longer than those treated by angioplasty -- and that both bypass surgery and angioplasty provided more benefit for patients than medicine alone.
Because bypass surgery has shown the greatest longevity benefit in treating three-vessel disease -- "potentially the most lethal form of heart disease," says Smith -- "it's the clear winner for many of those patients."
Ohman concurs. "CABG certainly offers the best long-term solution for some people. The more severe the disease and the more vessels are involved, the more appropriate surgery becomes."
"Select patients do require intervention beyond medical management," Califf says. "In those cases, it's the doctor's responsibility to make sure those patients understand the potential benefits and risks of the procedure they're being offered."
Because it is recommended as both a singular strategy and for use in conjunction with PCI and surgery, medical management actually transcends and supplements all other multi-vessel disease interventions.
Medically managing CAD means treating the condition with non-surgical methods that include drug therapies and/or modification of lifestyle factors such as diet, exercise, smoking, and stress management.
These strategies also help prevent further deterioration of the heart muscle in patients with existing damage.
"Medical management is the bedrock of treating coronary disease," says Califf. "Regardless of anything else patients have done, medical treatment should be the standard of good medical therapy and the first option we offer our patients.
"The Duke data(6) show that patients who are on multiple effective treatments -- which can be a first-rate aspirin, beta-blocker, and statin, available for four bucks a month from Wal-Mart -- have about a twofold reduction in their risk of death compared to patients who do not adhere to their medication regimens.
"The issue is that the real benefit is in medical therapy," Califf continues.
"PCI doesn't prolong survival in most patients, so you're not losing anything there by going with medical management, and CABG obviously has a higher risk than medical treatment."
"If we cardiologists could just do our jobs in our own treatment environment and give patients simple four-dollar-a-month plans, we would save literally thousands of lives," he says.
"We need to give patients the important treatments first, and if those fail, then try the expensive and risky treatments."
Smith agrees that medical management plays an important role for surgical patients, and its use as an alternative to both PCI and CABG may be underutilized.
"Advances in medical therapy have led to more promising results than anticipated in treating patients with one- and two-vessel disease, whom the COURAGE trial(7) showed aren't being helped as much with PCI."
The key to the best outcome? Honest dialogue.
Since each multi-vessel disease intervention has its pros and cons, how does one decide which is likely to have the best outcome for a given patient?
By having a truthful and thorough doctor-patient conversation, these experts say.
"Many doctors tell their patients, 'You've got bad blockages, and we need to bypass or dilate those blockages because if we don't, you're going to have a heart attack or die,'" Califf says.
"And that's simply not validated by the randomized trials; it's not true. But it's something we frequently tell our patients because it avoids a much longer discussion about what's really going on in terms of the risks versus the benefits of these various interventions."
Many people assume, for instance, that minimally invasive procedures are inherently safer -- and therefore always "better" -- than open surgeries.
Take the surgery-versus-PCI issue, for example.
"Surgery has risks like pain, infection, and recovery time that people understand up front," Smith says.
"But multi-vessel coronary disease patients should understand that PCI's ongoing cumulative risk of restenosis is less obvious, with studies showing that surgery compares more favorably to PCI the longer patients are followed."
Patients may have different perceptions of risk when considering medical management, as well.
Some may perceive this strategy as having the lowest risk because it doesn't involve any type of surgery. Others may see it as being more risky than the other options because they don't believe medication and lifestyle changes can successfully treat their heart disease.
"It's only natural for patients to think that if they have a stent placed or undergo a bypass that their disease is 'fixed' -- and doctors can easily get away with saying, 'It's lucky we found this blockage; now we can fix it,'" Califf says.
"A doctor who offers patients a potentially risky procedure must be able to show that it's likely to help them."
Another issue, Califf says, is that many patients have difficulty translating probability into risks that are meaningful to them.
For example, when comparing a treatment said to have a 10 percent risk of death with one said to have a 90 percent survival rate, people are more likely to choose the second option, even though the actual degrees of risk are equal.
Patient factors that figure into the risk-versus-benefit equation commonly include:
Age and health status: A patient may be too elderly or ill to withstand surgery, for example -- or to wait for the effects of medical intervention.
Medical management alone or in conjunction with PCI may be the most appropriate choice for someone with minimal disease.
Goals, values, and concerns: A big issue is quality versus quantity of life. Some people prefer better years to more years; some, the opposite.
Patients might think about what they hope to achieve through treatment. The stamina to keep running marathons? The ability to perform daily activities and play with the grandchildren? Relief from debilitating symptoms?
Other factors can include patients' affinities for (and aversions to) particular treatments, insurance or financial concerns, and so on.
Lifestyle and compliance: Some patients follow their doctor's instructions to a tee; others don't.
Some aren't likely to quit smoking, take up regular exercise, or improve their diets; others view their condition as a call for meaningful lifestyle change. Some are very self-motivated; others might benefit from working with a health coach.
Other factors also can come into play when choosing a treatment for multi-vessel disease.
"The patient made me do it" phenomenon: While patients are encouraged to educate themselves and take a proactive role in their own health, they are increasingly arriving at their initial cardiologist visits with Internet printouts in hand and a treatment in mind -- without having discussed their individual risks and benefits with their doctors, and frequently armed with data that are murky at best.
Unclear and/or biased data: Unfortunately, the large body of existing research data about treating multi-vessel CAD can lead to confusion, not clarity. The length and type of the study, as well as the number of participants, obviously influence the quality and meaning of the data.
And different uses and interpretations of the word "multi-vessel" -- which can mean two, three, or four vessels -- mean that data from studies of patients with different degrees of disease may be combined, accounted for multiple times, and/or simply unclear.
"Most 'multi-vessel' CAD studies have in fact looked only at patients with two-vessel disease -- not three- or four-vessel disease -- and the distinctions are critical in terms of both compromised patient health and the interpretation of the data," Smith says.
"People can take these results to mean what they want them to mean when making a case for or against a particular therapy."
Physician expertise and bias: A physician or hospital's experience with and/or bias toward particular treatments plays a role in which strategies are recommended to people with heart disease.
"It's one thing for doctors to advocate for the procedures they do, but it can be an entirely different thing for them to advocate for their patients," Smith says.
"We should help our patients develop a perspective beyond what happens today, present them with information honestly, and never present a procedure as an option when another one would be more appropriate."
Califf agrees. "Let's have the courage to tell our patients the truth about what we know about each of these treatment strategies, and take the time to explain all of the risks and benefits."
While the morbidity and mortality associated with coronary artery disease is devastating, both doctors and patients can thank ongoing advances in medicine for the variety of lifesaving treatment options available today.
Selecting the right one to treat a patient's multi-vessel disease means working together to make a carefully informed, patient-centered decision.
Robert M. Califf, MD, is the Donald F. Fortin, MD, Professor of Cardiology, vice chancellor for clinical research, and director of the Duke Translational Medicine Institute.
E. Magnus Ohman, MD, is a professor of medicine and director of Duke Heart Center's Program for Advanced Coronary Disease.
Peter K. Smith, MD, is a professor of surgery and chief of cardiovascular and thoracic surgery at Duke.
This article was first published in the Summer 2008 edition of DukeMed Magazine.
Footnotes
1. 3 N Engl J Med. 2007 Mar 8;356(10):1009-19. Epub 2007 Feb 12.
2. J Am Coll Cardiol. 2007 Nov 20;50(21):2029-36.
4. Heart. 2004 September; 90(9): 995-998.
5. Ann Thorac Surg. 2006 Oct;82(4):1420-8; discussion 1428-9.
6. Circulation. 2006 Jan 17;113(2):203-12. Epub 2006 Jan 9.
7. N Engl J Med. 2007 Apr 12;356(15):1503-16. Epub 2007 Mar 26.
