It’s been seven months since Daniel Hook had successful surgery at St. Michael’s Hospital to treat an abdominal aortic aneurysm (AAA), a condition where there is swelling or ballooning in the aorta. Known as a “ticking time bomb” because it can grow undetected for years, AAA is usually deadly if the aortic aneurysm ruptures or bursts.

Hook’s AAA was discovered by clinicians at St. Michael’s, who performed an emergency surgery on him in 2022 to remove a blood clot from his leg. The care team monitored the AAA until it was large enough to warrant surgery and, in December 2023, scheduled the 63-year-old for a minimally-invasive aneurysm repair in Operating Room 20 per cent one of the hospital’s new hybrid ORs.

Despite existing recommendations for aneurysm screening, there are currently no established screening programs in Canada.

On the day of the surgery, Vascular Surgeon Dr. Charles de Mestral and colleagues treated the AAA with an endovascular stent to relieve pressure from the aorta. The stent was inserted and placed into Hook’s aorta via a needle puncture in the groin – or as Hook recalls “two quick pokes in my hip.”

After a brief two-night hospital stay, Hook returned home.

“I started being active when I got home. I started going for daily walks and following my doctor’s directions,” he said, noting that since his surgery he’s quit smoking, cut out alcohol and caffeine and is working on reducing his sugar intake. “I feel happy, like I can be active again.”

Hook will continue to receive follow-up care from St. Michael’s, including annual ultrasounds of his abdomen to monitor the stent. He says while he was initially very nervous to have a second surgery after the removal of his blood clot, he always felt very safe with his care team.

“I got a lot of strength from the wonderful people at St. Michael’s. I was overwhelmed by how everybody was there for me. I had no reservations, no hesitations. I feel very positive about the whole experience,” he said.

De Mestral was also happy with the outcome. “This was a textbook minimally-invasive abdominal aortic aneurysm repair with a rapid recovery. As our first case in the new hybrid OR suite, it could not have gone more smoothly,” he said.

In addition to top-of-the line OR equipment, de Mestral also credits the successful surgery to collaborative pre-operative planning of all AAA repair cases by vascular surgery and interventional radiology colleagues and, to a strong OR team of anesthesiology, nursing and medical imaging professionals, as well as trainees.

The call for AAA screening

In Canada, about 20,000 people are diagnosed with AAA every year. Risk factors for AAA include a family predisposition, as well as smoking, high blood pressure, high cholesterol and hardened arteries. AAAs are much more common in men. The size of an AAA is closely linked to the risk of it bursting.

The main treatment for an AAA is to manage risk factors and monitor the aneurysm risk with regular ultrasounds of the aorta. Surgery is recommended only once the risk of the AAA bursting exceeds the risk of surgery. Early detection and monitoring provides the opportunity to fix the AAA before it bursts, says de Mestral.

“The concern is that an aortic aneurysm rarely causes any symptoms, but it’s at risk of bursting,” he said. “If it bursts, most people don’t survive. Most people don’t make it to the hospital, and survival rates are not high for those who do make it in time to get an emergency surgery.”

De Mestral is among a group of researchers who are calling for the creation of provincial AAA screening programs.

Despite existing recommendations for aneurysm screening, there are currently no established screening programs in Canada.

Earlier this year, de Mestral and his research team published a study in the Canadian Medical Association Journal that found that AAA screening is cost-effective and results in fewer AAA-related deaths.

Based off models, the study found that screening adults 65 and older reduced AAA-related deaths by 84.9 per cent among males and 81 per cent among females. Screening for AAA was increasingly cost-effective in populations with higher AAA prevalence.

“Our results support one-time ultrasonography screening for AAA in Ontario for males aged 65-75 years, consistent with current screening recommendations. Screening for females aged 65-75 years is likely cost-effective despite lower prevalence rates,” the study concluded. “Given our findings, the implementation of provincial AAA screening programs should be seriously considered.”

De Mestral said Ontario Health is currently looking to establish an aneurysm screening program, and data from this study will help move the development of the provincial program along.

 “The research is well tied-in to policy,” he said. “Often research is done with the hopes that it will inform practice. We know that the data from our study are actively being used in the planning of an AAA screening program in Ontario. That’s pretty exciting.”

By Marlene Leung
Marlene Leung is a Senior Communications Advisor at Unity Health.