A method that predicts someone’s risk of tears in the body’s largest blood vessel could avoid a condition that is rarely discovered early enough.
Summary
A method that predicts who might have an enlarged aorta could eventually help to reduce deaths from tears in this vital blood vessel. Heart scans from almost 37,000 UK Biobank participants were used to create a scoring system that estimates how factors such as age, sex, body weight and blood pressure influence the risk of having an enlarged aorta. This could eventually allow doctors to better identify at-risk people and help them to prevent further damage to their blood vessels.
A method that predicts enlarged aortas – the body’s largest blood vessel – could eventually help to reduce deaths from rare but life-threatening tears in this vital vessel.
The aorta is the main blood vessel that takes oxygen-rich blood from the heart to the rest of the body. If a section of the aorta’s wall is weakened, it can bulge outwards, which can turn into a tear of the blood vessel’s inner layer. This can slow or stop normal blood flow and, in extreme cases, result in the aorta rupturing entirely.
Aorta tears are rare but life-threatening. And there aren’t any warning signs: enlarged aortas don’t tend to cause any issues until a tear appears. People aren’t generally screened for aorta issues, so they remain undiscovered unless someone gets a chest X-ray, magnetic resonance image or other scan for unrelated reasons.
The silent threat of aortic tears
In the hospital, we see people after they’ve had the bad consequences of a big aorta. But right now, we don’t really have a way to try to identify people who are at high risk before that.
Dr James Pirruccello, University of California, San Francisco, US
“In the hospital, we see people after they’ve had the bad consequences of a big aorta,” says study co-leader James Pirruccello from the University of California, San Francisco, US. “But right now, we don’t really have a way to try to identify people who are at high risk before that.”
Pirruccello and his colleagues developed a way to predict who might have an enlarged aorta by simply looking at factors such as age, sex, body weight and blood pressure. From magnetic resonance images from almost 37,000 UK Biobank participants the team developed a score that describes how these factors influence the risk of having an enlarged aorta. Eventually, doctors could use such a score to pick out people who are at high risk of aortic tears and refer them for further screening – rather than having to do expensive and time-consuming screening on everyone.
Balancing accuracy and practicality
This is the first step down a path that helps us understand if doing these predictions is useful – long term, does it keep people alive longer and does it reduce suffering? Without UK Biobank, we wouldn’t even have the chance to ask that question and eventually get an answer.
Dr James Pirruccello, University of California, San Francisco, US
“Of the people with a positive score, about one out of every 10 would actually have a big aorta,” Pirruccello explains. Although this sounds far from perfect, it’s similar to a mammogram or a colonoscopy: most people who are screened don’t end up having cancer. “The goal isn’t to just have a perfect score,” he says; it’s more about a realistic balance between screening nobody and screening everybody.
If screening finds an enlarged aorta, there are ways to prevent further damage: blood-pressure lowering medications, or surgery to strengthen or replace the aorta’s damaged section.
Pirruccello says that his scoring system would need to be carefully tested before it can be used in the clinic. “This is the first step down a path that helps us understand if doing these predictions is useful – long term, does it keep people alive longer and does it reduce suffering? We don’t know enough yet to understand if it’s going to help us with those two things. But without UK Biobank, we wouldn’t even have the chance to ask that question and eventually get an answer.”