(Republished with permission from the St. Louis Post-Dispatch. This article originally ran in the Business section on Sunday, August 21, 2005)
By Judith VandeWater
Of the Post-Dispatch
The supply of candidates for open-heart bypass surgery – the bread and butter of most cardiac surgery practices – is on the decline. Fewer people smoke. Drugs to lower cholesterol and control blood pressure are helping many patients keep heart disease in check.
Patients who develop significant blockages are more favorably disposed to the closed-chest treatment offered by interventional cardiologists than they are to major surgery. Drug-eluting stents have given all but the sickest patients the choice. These stents, the wire-mesh scaffolding that interventional cardiologists use in combination with vessel-widening angioplasty, are coated with drugs that slowly wash into the bloodstream and prevent reclotting.
Dr. Nader Moazami, chief of cardiac transplantation at Barnes-Jewish Hospital and an assistant professor of cardiac surgery at Washington University Medical School, said it is premature to signal the decline of cardiac surgery. “There is no reason to panic; the profession is still at its pinnacle and will continue to grow,” he said.
Heart disease is the leading killer in the United States, and with the population aging, there will continue to be an assured demand for services. Moazami said cardiac surgeons will stay busy with bypass procedures, repairing and replacing heart valves and implanting devices to stabilize heart rhythms. The burden will be on interventional cardiologists to show that patients who have valve work done via a catheter will live as long – and as well – as those who have surgical repairs.
There is evidence to suggest that the decline in bypass surgeries is affecting the job market for cardiac surgeons. Dr. Richard Lee, an assistant professor in cardiothoracic surgery at St. Louis University School of Medicine, said the market for newly minted heart surgeons is soft.
Lee surveyed the 130 to 140 physicians graduating from cardiothoracic surgery fellowships last year on their job prospects. The 40 percent who responded said the market was favoring chest surgeons and vascular surgeons. The consensus was there were few slots for cardiac surgeons because veterans were staying in their jobs longer, possibly to offset the decline in practice income.
Dr. Jason Wollmuth, a fourth-year fellow in interventional cardiology at Washington University, said his job prospects are rosy. Wollmuth, 33, graduates in July. He has made some preliminary probes to feel out the West Coast job market, with an eye toward his home state of Oregon. “The majority of groups I’ve talked to are looking to hire, if not now, in the next year,” he said.
“I don’t believe in all of medicine that there is as dynamic a field,” said Dr. John M. Lasala, director of interventional cardiology and cardiac catheterization at Barnes-Jewish Hospital. “People are so optimistic that we can do things in so-called noninvasive ways, there just doesn’t seem to be any limit to what the people whose imaginations are spurred by this field will take on.”
Patients are receptive because interventional cardiology is less invasive than open-heart surgery, and they recover sooner.
But surgeons are skeptical because the new techniques and devices lack a long-term track record and have not been proved to produce better patient outcomes than surgery.
Tools of the trade
Invasive cardiologists use imaging equipment to guide flexible catheters through the bloodstream and into the coronary arteries. Once inside, they can diagnose and clear many blockages. In most cases, after vessel widening, they implant one or more stents to keep the artery flowing.
Invasive cardiologists may determine that surgery is the best recourse for a patient, but surgeons say the cardiologists are holding onto more patients than ever before.
Lasala said the drug coatings on stents have reduced the likelihood an opened artery will reclog to 3 percent from 17 percent. Strides in stent design have allowed interventional cardiologists to use the devices to treat more-complex blockages and multiple blockages. Still more advanced designs are on the horizon.
Bypass surgery and stenting both work by opening clogged arteries to improve blood flow to the heart muscle. Surgeons go around blockages. Interventional cardiologists go through them.
Doctors judge the severity of heart disease by the number and type of vessels caked with cholesterol plaque. When the plaque ruptures, it oozes fat and tissue. In a heart attack, blood clots form at the fissure and stop the flow of blood, starving the muscle.
Blood enters the arteries through the aortic valve at the top of the heart. From there, it is shunted into the right and left arteries. A blockage in the left main coronary artery is lethal. The left main quickly splits into the left anterior descending artery and the circumflex artery, which feeds the back of the heart. The main branch of the left anterior descending artery is known as the “widow maker” because it supplies the largest chunk of heart muscle.
Single-vessel disease involving the right artery or the circumflex artery is usually treated by angioplasty to widen the vessel, and stenting. Two-vessel disease falls in a gray area where the decision to stent or do surgery may be influenced by a doctor’s expertise. Traditionally, patients with blockages in three vessels were candidates for bypass surgery. Lasala and other interventional cardiologists are challenging that convention.
By the numbers
Moazami said the improved performance of drug-eluting stents does not change the indications for stenting. “Putting three or four stents in multiple vessels has never been proven as good as three-vessel bypass,” Moazami said. “Nevertheless, there is significant hype about stents.”
Dr. Steven Eisenberg, a cardiothoracic surgeon and chief of surgery at St. Anthony’s Medical Center in south St. Louis County, said that in an ideal world, every patient would talk to a cardiologist and a surgeon and make his or her own decision on what is best.
“What happens in the real world is a patient goes to a primary-care doctor and gets sent to a cardiologist and they make the decision. There is clearly a financial incentive to do a stent. I am not trying to say there are not a lot of ethical cardiologists. There is an economic advantage to cardiologists using stenting.”
Eisenberg said some cardiologists are too conservative when it comes to stenting, and some don’t believe in surgery and go overboard with multiple stents. “Surgeons call it the full metal jacket,” he said.
Moazami said surgeons are not opposed to stenting, but research has shown bypass to be superior for certain patients. Diabetics, in particular, fare better with bypass, he said.
Early patient outcomes with drug-eluting stents have been highly favorable, but only time will prove the lasting benefit of the procedure. Bypass surgery has been in use for decades, and its enduring benefits have been proved in randomized clinical trials.
Earlier studies have shown a greater likelihood that symptoms such as chest pain would reappear with stenting than with bypass, thus necessitating the need for repeat procedures.
A study published in May in the New England Journal of Medicine found that patients with severe heart disease, defined as two or three blocked arteries, were more likely to die within three years when they were treated with stents rather than with bypass.
Washington University’s Lasala downplayed the results as an anomaly – the study is the first to show a difference in death rate between stenting and bypass. Importantly, the study is based on data collected before the advent of drug-coated stents.
A large randomized comparison in Europe, the Arterial Revascularization Therapies Study II, has shown no difference in the death rates between patients treated with drug-coated stents and those treated with bypass. Diabetics in the trial fared no better with bypass than stenting. The stent group required more repeat procedures than the bypass group, Lasala said.
A government-funded, randomized study just beginning in the United States will compare drug-eluting stents to bypass surgery for people with multiple-vessel disease or diabetes.
Pushing the envelope
Lasala has been applying stents to a very complex patient base. Recently, he performed two surgeries with Moazami using a Tandem Heart, an external pump that is attached via catheter to the heart. The pump allowed Lasala to put stents in two patients who were deemed too sick to survive open-heart surgery.
Later this week, Lasala will screen his first candidate for a randomized trial that will compare mitral valve repair surgery to a closed-chest fix using a clamp called the Evalve. The valve is inserted in a catheter that is threaded through a vein and into the heart across the atria and mitral valve. Another doctor will direct a camera inside the patient’s beating heart and tell Lasala when he is in the correct position to deploy the clamp.
“This sounds very easy, but it takes hours to do,” Lasala said.
The clamp, which looks like a housefly when deployed, keeps the valve from regurgitating blood backward. Lasala hopes to schedule his first Evalve procedure next month.
A medical team in France has implanted the first aortic valve to be inserted in a closed-chest procedure. The valve is inserted inside a stent in a procedure used to treat aortic stenosis, the calcification of the aortic valve. There is no medical treatment for the debilitating condition. Patients who are too sick to tolerate surgery suffer crippling shortness of breath. The device offers hope for symptom relief. “I think this is going to be revolutionary,” Lasala said.
The aortic valve stent trial in humans is just beginning at medical centers in the United States. Lasala said it could be two years before the trials are widened to other medical centers.
Lee, of SLU, said there is no guarantee that cardiologists will be able to successfully replace … valves “as well as we can surgically today.”
“There have been artificial heart devices around for more than a decade. In the 1970s, Time magazine predicted an artificial heart and said it would be out in 10 years. Here it is 2005, and we are still waiting.”
Reporter Judith VandeWater
Copyright 2005 St. Louis Post-Dispatch, Inc.