By: Norman Bauman for Veins1
In 2002, Elizabeth II, Queen of England, knighted Mick Jagger for "services to popular music." She also knighted Peter R.F. Bell, MD, FRCS, for "services to surgery."
Dr. Bell's American friends are still joking about it.
"You don't get a castle or a horse," Dr. Bell protested. "You get upgraded in planes occasionally."
Dr. Bell's services were in transplantation and vascular surgery.
In the late 1960s, Dr. Bell recalls in his Yorkshire accent, he wanted to be part of a new, evolving medical specialty. So he went into vascular surgery and transplantation, which was just getting started. He left Scotland for the U.S., and returned to teach. So he's at home in America, where he's often invited back to lecture.
He was also part of the revolution of evidence-based medicine, the idea that doctors should use treatments that have been proven by scientific studies.
At the 2006 Veith Symposium on vascular surgery in New York City, Dr. Bell gave some controversial lectures. He argued that stents should be used in elderly patients with abdominal aortic aneurysms. He argued that stents should not be used in carotid artery stenosis. Stents are tubes made of wire mesh or fabric to repair blood vessels. He recommends statins, which have dramatically reduced stroke – and takes them himself.
He gave a tip on how to pick a vascular surgeon: Go to a hospital that's done a lot of procedures, since the institution is more important than the individual doctor.
Dr. Bell first became interested in vascular surgery when he treated patients with kidney failure. In dialysis, the doctor withdraws blood from an artery, purifies it, and returns it to a vein. The volume of blood is too great for veins to handle, so a vein must be enlarged. The doctor sews a section of artery and vein together, called a fistula, and arterial pressure enlarges the vein. Dr. Bell invented an operation for creating a fistula.
Dr. Bell wanted to be a surgeon ever since age 3. At medical school in Sheffield, England, he got into trouble for adding laboratory alcohol to the punch. He taught surgery at the University of Glasgow for 10 years, but spent a year in 1967 in Denver, Colorado, where he learned from Dr. Thomas E. Starzl how to transplant livers and kidneys. He returned to Glasgow, and in 1973 become professor of surgery at a new medical school in the University of Leicester.
Abdominal aortic aneurysms
At the Veith Symposium, Dr. Bell moderated a panel and presented a paper on the treatment of abdominal aortic aneurysms.
The diameter of the aorta grows with age, but shouldn't be larger than 2.2 centimeters (almost an inch). In 5 percent of men over 65, the aorta weakens and enlarges, like a bicycle tube. That's called an aneurysm. If that aneurysm enlarges enough, it bursts, usually fatally.
An abdominal aortic aneurysm can be cured with surgery, with some risk. A small aneurysm has a small risk of death and a large aneurysm has a large risk of death. When the aneurysm grows to 5.5 centimeters, the diameter of a doorknob, the risk of death from the aneurysm becomes much greater than the risk of surgery, and doctors usually recommend surgery.
There are two kinds of operations, Dr. Bell explained. One is to open up your belly and replace the weakened, enlarged section with a Dacron stent. The other, less invasive way is to reinforce the aorta from inside by threading a stent up from the artery in your leg. Vascular surgeons have learned "to treat pipes from the inside, rather than from the outside," he said. This is called an endovascular aneurysm repair, or EVAR.
At first glance, EVAR looks better.
First, the death rate during surgery is 5 percent for open surgery, versus 2 percent for EVAR, said Dr. Bell. So with EVAR, "you gain straightaway by having a 3 percent less chance of dying in the immediate post-operative period."
Second, EVAR is the less invasive surgery, with less time in the hospital, faster recovery, and less pain. EVAR requires a one day hospital stay. Open surgery is major surgery, with general anesthesia, a large incision in the abdomen, time in the intensive care unit, four to six days in the hospital, and a long recovery time. "With EVAR you feel pretty good in about two weeks, back to normal," said Dr. Bell. "The open operation takes about three months."
To compare the two procedures, the British National Health Service has been following 1,082 patients for 4 years so far. Half were randomly assigned to open surgery, and half were randomly assigned to EVAR. The results are regularly published in The Lancet.
At the beginning, the EVAR group does better. But after 4 years, the number alive is the same, whether they had open surgery or EVAR. "So it's a short-term gain," said Dr. Bell. "After four years, we don't know, because the trial itself is only been going for four to five years and we are [still] following people up.
"There is a supposition that EVAR is less durable, maybe," said Dr. Bell. With open surgery, the stents are sewn in, and surgical stitches are very secure. With EVAR, the stents are held in from the inside, with hooks. After five years, they may start to loosen up. The only way to find out is look at 10-year outcomes.
Dr. Bell concludes that open surgery or EVAR "depends on your age."
If you are 85, Dr. Bell would say, "Look, you're 85, we know this thing lasts for 4 years, 85 years old is 85 years old, this is good for you, because you're not going to be here forever and therefore it's worth taking the risk."
If you are 55, Dr. Bell would say, "Look, we don't know whether it's going to last forever, I would have an open operation, because you're fit to take it, get it done with, no follow-up."
Maybe in 10 years time, Dr. Bell will be able to say, "You're 55, we've followed these things for 15 years, they're fine, you can have one of these."
The great hope of EVAR was that doctors would be able to use a less invasive operation in patients who were too old, too sick, or otherwise unfit for open surgery. The British National Health Service took another 338 "unfit" patients and randomized them into two groups. Half got the best medical treatment. Half got the best medical treatment plus EVAR.
The results were disappointing. For those "unfit" patients, EVAR had a high death rate (seven percent), as expected. But over four years, patients with EVAR didn't survive any longer than patients who had no surgery at all.
"The trial showed there is no difference in the two, but I don't agree with that," said Dr. Bell.
The study had flaws. First, some patients who were randomized to no-surgery got surgery anyway. A patient can always quit the study and get the treatment he or she wants. Second, six patients who were supposed to get EVAR died while they were waiting for surgery, but they were counted as EVAR deaths. This made EVAR look worse.
"If you have an aneurysm which is more than 5.5 centimeters in diameter, the chances of it bursting and killing you is something like 10 percent per annum," said Dr. Bell.
"So my view," said Dr. Bell, "is that the 'unfit' patients should all be offered an operation, because there's no 'best medical treatment' ethically really."
Carotid artery stenosis
Stenosis is the opposite of aneurysm. In aneurysm, the artery gets big and thin. In stenosis, the artery gets narrow and thick. This often happens from atherosclerotic plaque in the carotid artery, which you can feel pulsing on both sides of your neck. With stenosis, the artery can become blocked, or a piece of plaque can break off and block an artery up in the brain, causing stroke with paralysis, loss of speech, sight, or death.
There are two kinds of carotid artery stenoses, explained Dr. Bell - symptomatic and asymptomatic. Symptomatic is worse. He recommends surgery for symptomatic patients, but not for asymptomatic patients. He also recommends statins.
The symptomatic carotid artery stenosis gives you mini-strokes. "Usually, you lose the use of your arm or leg or speech or sight for a few seconds, and then it gets better again," said Dr. Bell.
The asymptomatic carotid artery stenosis narrows your artery, but you don't know it. "The doctor can hear a noise in the neck, a bruit," said Dr. Bell. The doctor can see it with ultrasound. "Or it might be found by an angiogram that you do for other reasons."
Surgeons can significantly reduce the risk of stroke with an operation called an endarterectomy. Through a small hole in the neck, they cut open the artery and remove the plaque.
For symptomatic cases, the evidence is "very good" that endarterectomy reduces risk of stroke, said Dr. Bell. Two randomized trials in 1990, one in the United States and one in Europe, found that for symptomatic patients, "it was much better to do an operation." Endarterectomy became standard treatment.
For asymptomatic cases, the evidence is "not so good," said Dr. Bell. Another randomized trial in the United States, and another in Europe, showed a "very small" benefit. But the surgery might do more harm than the stenosis. Many asymptomatic patients never have strokes.
If stents have fewer complications for abdominal aortic aneurysm surgery, maybe stents have fewer complications for carotid artery surgery too. Dr. Bell doesn't think so. "There have been a few randomized trials, but they're all flawed," he said. "In fact, they are complete nonsense." Most stents were placed in asymptomatic patients, who seldom get strokes anyway. They had more strokes than they would have if you left them alone.
But all these studies were done before statins. "Statins have made a huge difference," said Dr. Bell. "Just by taking statins you reduce your stroke risk by 30 percent."
Statins are not just for high cholesterol, said Dr. Bell. "If you have vascular problems you should have it anyway."
Dr. Bell takes statins himself. "My cholesterol was 7.4 mmol/liter," as the British measure it, or 266 mg/dL American style. According to the U.S. National Institutes of Health guidelines, total cholesterol is ideally under 200 mg/dL, and people over 240 mg/dL should take drugs.
"If you have a carotid stenosis which is asymptomatic, take your statins and don't have anything done," said Dr. Bell. "If you've got a stenosis which is symptomatic, have an operation done by the right surgeon."
Randomized controlled trials
"The best evidence, without a doubt, is a randomized controlled trial," said Dr. Bell.
In a randomized, controlled trial you have two different ways to treat someone and you don't know which is better, so you randomly assign them to one treatment or the other, as they come in the door. That way, everything else between the two groups is identical, except for the treatment.
Dr. Bell tells his patients, "We want you to join this trial because I'm your doctor, and I don't honestly know which is the best treatment here, and I want to know for you and for the future.
"If I knew I wouldn't be doing the trial," Dr. Bell tells them. "Then hopefully at the end of three, four, five years, we'll know which is better for the succeeding patients," said Dr. Bell. "They accept that.”
The worst evidence is saying, "I've done 105 of those and none of them died," said Dr. Bell. If he wanted those results, "I could just do easy cases.
“Doctors tell you that results have improved over the years after they adopted a new technique. But over the years anesthesia and post-surgical care also improve,” said Dr. Bell. “So they can't say it's the result of the new technique.”