Picture your aorta, your largest artery, carrying blood from the heart to your organs and limbs. Now picture a weak spot on the aorta’s wall; it balloons outward with every heartbeat.
It’s called an aneurysm, and you probably won’t know it’s there.
“It’s not like a heart attack where you can have a warning sign like chest pain. The aneurysm just sits there with no symptoms at all,” says cardiologist and researcher Dr. Thais Coutinho. But if the aneurysm ruptures or tears, causing a bleed, it can be deadly. With a thoracic aortic aneurysm (TAA) rupture, one-third of people collapse and die right away, without time for medical help.
Dr. Coutinho, with funding from Heart & Stroke donors, is working to make TAAs less deadly.
Healthy blood vessels are critical to your heart and brain health. While aneurysms can occur in any blood vessel, Dr. Coutinho is focused on the aorta.
Her pioneering research has found that when the aorta is stiff, it increases the risk that an aneurysm will grow faster. Her work could soon impact medical recommendations for treating TAA.
Dr. Coutinho is Chief of the Division of Prevention and Rehabilitation at the University of Ottawa Heart Institute and assistant professor of medicine at the University of Ottawa. She sees patients who have stable aneurysms in their aortas. Some got tested due to a family history, but most found out by accident when they got a chest scan for another reason.
Current medical recommendations suggest treating these patients with beta blockers to reduce their blood pressure, and then offering surgery only if the aneurysm reaches a certain size.
“But size does not tell the whole story,” says Dr. Coutinho. The recommendations are often based on men’s bodies and may not take some women’s smaller size into account, she says. Instead, she is focused on elasticity of the aorta, which is a marker of health of the aortic wall.
“Every time the heart beats, it generates a very intense pressure. The aorta is so elastic, it buffers some of that pressure,” she says. But if the aorta is stiff, an aneurysm has to take the brunt of the pressure — which could lead to a rupture.
Dr. Coutinho has been using ultrasound of the heart and other tools to measure the elasticity of the aorta and connect that, over time, with TAA expansion.
“We’ve found that aortic function not only seems to predict the future expansion of the aneurysm, but it does so better than any other clinical risk factor,” including TAA size, she says.
Dr. Coutinho always looks at the impact of sex and gender in her research. As chair of the Heart Institute’s Canadian Women’s Heart Health Centre, she educates other researchers and the public about sex, gender and heart disease, and the need for more research.
Women more likely to die
Previous studies found that women with TAA are three times more likely to have their aneurysm rupture and are 40% more likely to die if they have reduced aortic elasticity, compared to men.
Dr. Coutinho’s research added to this literature by showing that women’s TAA’s grow two to three times faster than men’s. While TAA is more common in men, elasticity seems to matter most for women.
Next, Dr. Coutinho plans to search for biomarkers that predict TAA expansion, to find a better way to determine the risk for complications once this silent disease is diagnosed, and eventually seek new treatment pathways. She’ll be continuing to analyze the difference between women and men in this research, and trying to tease out the importance of physiology and hormones.
In her work with the Canadian Women’s Heart Health Centre, she’s helped create a toolkit for heart researchers on how to look for sex and gender differences in their projects. “Every single researcher needs to have a gender lens in everything they do. If you don’t look for it, you don’t find it. Having this lens leads to better science, and better outcomes for the population.”