CMU studies on aneurysms find many surgeries unnecessary
A high number of patients with aortic aneurysms are getting unnecessary surgeries to repair them, according to a Carnegie Mellon University professor who is developing a better way to predict when an aneurysm is more likely to rupture.
"Just because the aneurysm is large it doesn't mean there is a risk of rupture," said Ender Finol, head of the Vascular Biomechanics and Biofluids Laboratory at CMU's Institute for Complex Engineered Systems. "I believe there is a high percentage of people that are being operated that don't need the surgery."
An aortic aneurysm is an abnormal bulge in the wall of the aorta, the body's largest and most important artery, which carries oxygen-rich blood.
The aneurysms tend to have no symptoms and are typically discovered by chance during X-rays. If they rupture, they can cause life-threatening internal bleeding. About 15,000 people die every year from aortic aneurysms, according to federal statistics.
Last year, vascular surgeons in Pennsylvania performed nearly 1,500 surgeries to repair aortic aneurysms in the abdomen, the section of the body where most of them tend to occur.
In Western Pennsylvania, the leading hospitals doing the surgeries were UPMC Presbyterian in Oakland, with 136 cases in 2006, and Allegheny General Hospital in the North Side, with 110 cases, according to the Pennsylvania Health Care Cost Containment Council.
To date, the best way to predict a rupture is by monitoring the aneurysm as it gets larger in diameter, said Dr. Satish Muluk, director of vascular surgery at Allegheny General. When it widens to 5 centimeters, doctors agree surgery is needed because that's the threshold when the artery is likely to rupture.
But Muluk believes size should not be the only parameter to determine whether it will rupture.
"There are cases in which a smaller aneurysm may rupture and a larger aneurysm may not rupture," Muluk said.
The technique under development at CMU intends to assess the risk by using factors other than size, including the shape and thickness of the arterial wall, Finol said.
Using images obtained through MRI or CT scans, researchers are creating three-dimensional models of the aneurysm. The images are run through computer software that, based on a set of assumptions such as blood pressure, can predict the distribution of the stress on the wall.
Measuring how much stress the wall can take -- akin to how much a piece of fabric can be pulled until it tears -- can better predict when it will rupture, Finol said.
Finol has received a two-year, $602,000 grant from the National Institutes of Health for the project. He expects to enroll about 50 patients from Allegheny General to test the technique.
Improved methods of prediction could benefit patients who often endure surgeries. Aneurysms can affect anyone, but are most often seen in men ages 40 to 70.
"Sometimes you have to (weigh) the risk of having a surgery of this kind against the life expectancy of the patient," Finol said.
Show commenting policy
TribLive commenting policy
You are solely responsible for your comments and by using TribLive.com you agree to our Terms of Service.
We moderate comments. Our goal is to provide substantive commentary for a general readership. By screening submissions, we provide a space where readers can share intelligent and informed commentary that enhances the quality of our news and information.
While most comments will be posted if they are on-topic and not abusive, moderating decisions are subjective. We will make them as carefully and consistently as we can. Because of the volume of reader comments, we cannot review individual moderation decisions with readers.
We value thoughtful comments representing a range of views that make their point quickly and politely. We make an effort to protect discussions from repeated comments either by the same reader or different readers.
We follow the same standards for taste as the daily newspaper. A few things we won't tolerate: personal attacks, obscenity, vulgarity, profanity (including expletives and letters followed by dashes), commercial promotion, impersonations, incoherence, proselytizing and SHOUTING. Don't include URLs to Web sites.
We do not edit comments. They are either approved or deleted. We reserve the right to edit a comment that is quoted or excerpted in an article. In this case, we may fix spelling and punctuation.
We welcome strong opinions and criticism of our work, but we don't want comments to become bogged down with discussions of our policies and we will moderate accordingly.
We appreciate it when readers and people quoted in articles or blog posts point out errors of fact or emphasis and will investigate all assertions. But these suggestions should be sent via e-mail. To avoid distracting other readers, we won't publish comments that suggest a correction. Instead, corrections will be made in a blog post or in an article.
- Obama promises to veto Republican vote to reverse NLRB rule on unions
- Railroad measure awaits House approval
- Natural gas royalties lawsuit hinges on transaction date
- Maryland’s Senator Mikulski announces retirement
- Lawmakers press Veterans Affairs for improved access to rural health care
- $4.8M in gold taken in armored truck hijacking in North Carolina
- Homeland Security panned for passing on bio-threat technology
- Carnegie Mellon expert to school Congress on security
- Florida fisherman’s high court win spurs call for legal reform
- Nurse who survived Ebola virus says Dallas hospital failed her
- Supreme Court justices split on states’ panels to prevent gerrymandering