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Vital Signs

Surgeon leads aneurysm screening campaign

Just below the kidneys runs a section of the abdominal aorta, a blood vessel about the size of a small garden hose. It's a workhorse, delivering blood to the whole lower half of the body. But after 50 or 60 years of use, its walls can weaken, sometimes creating a dangerous bulge known as an aneurysm. If the aneurysm gets too big and too weak, it can rupture.

Huge: "That's a calamity that most people don't survive," says Dr. Robert Zwolak, a vascular surgeon at DMS. "Of those lucky enough to get to the hospital alive, there is a huge emergency surgery," and about 50% of those who undergo emergency surgery don't survive. Some 15,000 people die each year in the U.S. of ruptured aortic aneurysms.

Zwolak was tired of seeing patients die from aneurysms that could have been detected by ultrasound and treated before they ruptured. So in February 2004, he helped the Society for Vascular Surgery found the National Aneurysm Alliance (NAA), an organization dedicated to reducing deaths from abdominal aortic aneurysms (AAAs). As the head of the NAA, Zwolak has been lobbying Congress since mid- 2004 to require Medicare to cover ultrasound screening for those at risk of AAA—which includes everyone over 55 who smokes or has smoked, has high blood pressure, has evidence of atherosclerotic vascular disease, or has a family history of AAA.

Though screening for many diseases, especially cancer (see here), remains controversial, the benefits of AAA screening are conclusive. "If we find an aneurysm before it's ruptured, we have a

Zwolak: now a political "operator," too.

95% to 98% cure rate," says Zwolak. And unlike cancer, there are clear benchmarks for what size aneurysms are likely to cause problems. "If it's a 'baby' aneurysm, you might follow it once a year with an ultrasound because that's how slowly they grow," Zwolak says. "If it's medium, say between four and five centimeters in diameter when it's discovered, you'd look with an ultrasound every six months. And then when it gets above five—in men we think five and a half is the magic number—that's the point at which the risk of the thing rupturing is significant enough that it's worth undertaking a fairly large-magnitude surgery to fix it."

Fix: AAAs can be "fixed" with open surgery or with a newer, less-invasive procedure. In open surgery, a piece of

synthetic tubing is sewn in place of the weak segment. "In concept, it's incredibly simple," says Zwolak. But in practice, it's a "very big operation"; even when done on a nonemergency basis, 3% to 4% of patients don't survive.

The less-invasive procedure has much better outcomes—just 1% to 2% mortality. It involves only a small incision in an artery in the leg. A device about the diameter of a pen is then fed up into the abdominal aorta. Once in place, the device deploys a stent graft that spans the length of the aneurysm and descends into the iliac arteries. Now, says Zwolak, "more than 50% of [elective AAA surgery] patients at Dartmouth—and I think that's pretty representative of major medical centers across the country—are getting these minimally invasive grafts."

Though lobbying is a new role for Zwolak, he's found it relatively easy because, he says, he "can obviously speak with great sincerity and experience." He and the NAA got a boost in their campaign when earlier this year the U.S. Preventive Services Task Force endorsed AAA screening for men aged 65 to 75 who smoke or have smoked. "For . . . men smokers they got it right on the nose," says Zwolak. "But I really think they dropped the ball for women," he adds, and "for people with family histories that are positive."

Soon: But armed with that recommendation, and bipartisan support, the NAA hopes to get its legislation before Congress soon. "We're cautiously optimistic that before they go home for Christmas this year, we'll get this passed," Zwolak says.

Jennifer Durgin

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