The silent killer

An aneurysm is a swelling in a blood vessel where the wall thins and balloons out. If it swells too much, it will rupture. When the aneurysm is in the aorta, the large artery that carries blood from the heart to the rest of the body, a rupture usually means death. Aortic aneurysms claim the lives of more than 15,000 people in the United States annually, largely because "95 percent of the time, there are no advance symptoms," says John Elefteriades ’72, ’76MD, professor of cardiothoracic surgery at the medical school. When an aneurysm is discovered in time, it's most often "incidentally, when a person is being examined for a different reason."

But Elefteriades and colleagues at Yale and two California companies are developing a simple blood test to identify these time bombs before they explode. By analyzing blood from 58 patients with thoracic aortic aneurysms (TAA) and comparing it with blood from the patients' spouses (whose aortas were normal), they discovered key genetic and blood chemistry differences between the two groups. The test they designed was about 80 percent accurate in its first trial (described in the October issue of the journal PLoS One). Further trials are now underway, and if they work, Elefteriades plans to start a large-scale trial immediately. Since aortic aneurysms tend to run in families, he says, "my hope is that we'd sample family members first, and then eventually be able to use it as a general screening test, like the PSA for prostate cancer."

Those who test positive can receive regular echocardiograms to confirm the diagnosis and track changes in aortal width. Preemptive surgical repair can often prevent disaster.