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Dr. Maral Ouzounian's first official day at the Peter Munk Cardiac Centre (PMCC) was very much a "trial by fire".
"It was July 15, 2013, and Dr. Viv Rao, Head, Division of Cardiovascular Surgery at the PMCC, had told me to just settle in and take it easy for the first few weeks," recalled Ouzounian. "But that was not to be. My very first day of work I was faced with a patient presenting exactly the type of clinical challenge that had essentially brought me to Toronto."
That challenge is complex aortic disease.
Celebrating Doctors' Day in Ontario throughout May
Every day, more than 320,000 patients across the province are treated and cared for by a doctor. Whether it's in a hospital, a long-term care home, a clinic or at home, Ontario's doctors are making a positive difference in the lives of patients by providing high-quality care when it's needed most.
The Ontario Medical Association will launch a public campaign for Doctors' Day on May 1 until the end of the month to mark the birthday of Canada's first female physician, Dr. Emily Stowe.
Spotlight on Ouzounian: her career at-a-glance
Ouzounian, Cardiac Surgeon and Surgical Scientist, was recruited to the Peter Munk Cardiac Centre to help fill an identified need and round out the Centre's already impressive expertise in this important area of cardiac medicine.
After receiving her MDCM degree from Montreal's McGill University, she completed her PhD at the University of Toronto. She subsequently completed her cardiac surgical residency at Dalhousie University in Halifax.
By then she had come to the attention of the cardiac surgery division at PMCC and Dr. Tirone David, the Melanie Munk Chair in Cardiovascular Surgery - an internationally renowned pioneer in aortic surgery, and the developer of an innovative valve-sparing aortic root replacement procedure that bears his name (the
David Procedure ).
David helped to arrange a fellowship at the prestigious Texas Heart Institute in Houston. There she worked with the noted Dr. Joseph Coselli, another pioneer and the world's foremost specialist in thoracoabdominal aortic surgery.
Aortic aneurysms explained
Naturally, Ouzounian continued her academic and clinical focus on aortic disease while in Texas.
"We are seeing a rise in the number of cases of aortic diseases, particularly aneurysms and dissections," she noted. "This may partially be due to better diagnostic techniques. In fact, now they are often being detected when they are not even being looked for. For example, a person may have a CAT scan for some other reason, and an aneurysm is detected."
Even when detected early, aortic aneurysms can present a clinical challenge.
An aortic aneurysm is a swelling, or expansion, in an artery (blood vessel), usually due to a weakness of damage in the artery wall. Blood pressure can cause the wall to bulge or balloon out at this weak point. As the aneurysm grows there is a greater risk of rupture which, in turn, can lead to series, and even fatal, complications.
"Aortic aneurysms can have a number of causes," explained Ouzounian. "They can be inherited, with a genetic element, or they can result from hypertension and other causes we don't yet understand. They can present differently and require different treatment approaches."
"If the aneurysm is uncomplicated, the basic approach is to determine if it's stable, if it's an appropriate size to treat and then fix it – either through open surgery or with an endovascular stent," she continued. "Treatments are much better now, thanks to major advances over the past several years, including the David Procedure, which was developed right here and has had a tremendous impact on the lives of patients with aortic root aneurysms."
Ouzounian's expertise will help save lives at UHN
Unfortunately, not all aneurysms are uncomplicated. Many, particularly thoraco-abdominal aortic aneurysms – located in descending thoracic and abdominal aorta – can present a greater clinical challenge, and require a more complex surgical approach.
The chance to study this type of surgery was one of the reasons Ouzounian targeted the Texas Heart Institute and Coselli for her fellowship.
"While these may represent only a small percentage of patients, the procedure is more complicated, requiring extra precautions, such as spinal cord protection," she noted. "At the time, many of these patients with extensive thoraco-abdominal aneurysms were being sent to Houston for treatment."
Now, with Dr. Ouzounian's help, this will change.
"We have a strong Vascular Surgery division at PMCC with expertise in both endovascular and open repair of thoraco-abdominal aneurysms. We have a very collaborative approach and all complex cases are discussed as a team. Our goal is to be able to provide the best possible treatment of thoraco-abdominal aortic aneurysms right here at the Centre," said Ouzounian. "University Health Network is already a Centre of Excellence in treating aortic aneurysms, and we want to be able to extend that to all patients, regardless of the type of treatment they require."
In addition to her clinical role, Ouzounian also focuses on research.
"We want to better understand how and why the artery wall expands," she explained. "We have formed a group of interested aortic scientists and are examining samples of aortic tissue taken from surgeries to look for clues to inflammatory changes, or for genetic indicators. We want to find ways to treat patients so surgery may not even be needed."
As for that first day…
Ouzounian found herself facing a 26-year-old man with a 10 cm ruptured thoraco-abdominal aortic aneurysm. The decision had to be made to send him to Texas or attempt a repair right away at the Centre. The choice was made – surgery on site.
"When we made the incision, there was a litre of blood in his chest," Ouzounian recalled. "He likely wouldn't have made it to Texas."
The patient underwent successful surgery and had his aorta replaced. "I saw him in my clinic," said Ouzounian, "I am happy to report that he has fully recovered."From May 1 until the end of the month, patients and their families, health care professionals and others can celebrate Doctors' Day by submitting a personalized thank-you message to their doctor through
www.ontariosdoctors.com or by tweeting #thanksdoc.