Deadly COVID-19 blood clot leads to first-ever intervention

Calgary physicians pioneer use of new life-saving technology

By  Blain Fairbairn

When a blood clot caused by a COVID-19 infection landed Brenda Crowell in the intensive care unit (ICU) at Foothills Medical Centre (FMC) — leaving her clinically dead for more than 30 minutes — a team of physicians in the FMC’s new Pulmonary Embolism Response Team (PERT) immediately stepped in with a new device never before used in Canada to remove the clot and save Crowell’s life.


“She went into cardiac arrest when she arrived at the emergency department and physicians rushed to revive her,” says Dr. Jason Wong, interventional radiologist and PERT member at FMC. “They weren’t very optimistic about her chances for survival, she was in very rough shape after having no pulse for such a long period of time.”

Crowell’s traumatic experience began in mid-April. She first developed symptoms of COVID-19 on April 15 and tested positive four days later. She isolated at home along with her husband and son for the next two weeks. By the end of April she was feeling better, but her symptoms suddenly worsened within a few days.

“I woke up on May 6 and couldn’t catch my breath,” says the self-employed 56-year-old bookkeeper. “My husband, who’s a retired paramedic, looked at me and said I was grey, so he called 911 right away and an ambulance was at the house before he was off the phone. I remember arriving in hospital but not knowing what was going on. I woke up a week later in the ICU and FaceTimed with my son who said, ‘Mom, we didn’t know if we’d be planning your funeral or not.’ I had no idea how seriously ill I had been.”

Diagnostic testing showed Crowell had pulmonary embolism (PE), which occurs when blood clots break off from vein walls and travel to the heart or lungs. PE is a very serious condition and can be fatal if not treated quickly. It’s the third-leading cause of cardiovascular death after coronary artery disease and stroke. COVID-19 is known to cause blood clots, and the risk increases in people with limited mobility and chronic health conditions — issues that affected Crowell.

There are three treatment options for severe PE: medication to break up the clot; open-heart surgery to remove the clot; or an embolectomy — a minimally-invasive procedure where an interventional radiologist guides instruments through the patient’s vessels with the assistance of a continuous X-ray to extract the embolism.

Under the guidance of Dr. Kevin Solverson, a respirologist who was part of Crowell’s care team, the PERT quickly determined an embolectomy would give her the best chance of survival with the least risk for complications.

Brenda Crowell, left, was the first patient in Canada to undergo an embolectomy using the new CAT12 Lightning catheter as demonstrated by interventional radiologist Dr. Jason Wong. Dr. Wong and his team saved Brenda’s life with the device after she developed deadly blood clots from a COVID-19 infection in May, 2021. Photo credit: Leah Hennel

Dr. Wong performed the procedure on Crowell using a new embolectomy device, the Indigo Lightning CAT12, to quickly extract the clot from Brenda’s lungs. The CAT12 is a catheter, about the size of a large drinking straw, which is specially designed for sucking out clots from large vessels like the pulmonary artery. This was the first time this device had been used in Canada.

“The procedure went really well,” says Dr. Wong. “We are really pleased with the extent and speed of her recovery, and it validates PERT’s mandate of being able to mobilize quickly and determine the right intervention to save the patient’s life. We’re very happy how this turned out for Brenda and her family.”

The PERT was conceived in 2017 at FMC and launched in 2019 under the co-leadership of interventional radiologist Dr. Eric Herget and intensivist Dr. Paul Boiteau. The need arose out of concern that some PE patients may benefit from invasive and advanced medical therapy, but these decisions require complex, multi-disciplinary coordinated care.

Through the PERT, a comprehensive rapid response team is assembled to assist in diagnosis, treatment and follow-up for high-risk PE patients. Similar response teams have been in place at FMC for years to treat stroke or heart attack patients, and these teams have had high rates of success in achieving positive patient outcomes.

“Through collaboration with emergency medicine, radiology, cardiac sciences, medical specialties and critical care, an evidence-based PE risk pathway was developed,” adds Dr. Wong. “This allows clinicians to flag high-risk PE patients and have PERT on standby for quick response. It’s another great example of how many different care teams work together in a complex, fast-paced environment to streamline and enhance patient care.”

Crowell and her family have since received both COVID-19 vaccinations and she’s feeling ‘amazingly well.’ Despite taking all precautions to avoid infection, it’s unknown where she picked up the virus. She says this experience has been an eye-opener — and she’s grateful to not only have survived, but to feel better than she did before getting sick.

“When I was leaving the ICU, one nurse said, ‘You know they think of you as a medical miracle.’ Well that’s because there were literally people all over the world praying for me,” she laughs. “Part of their prayers was that I would heal in double time — and I think that’s why everyone was so surprised.”

Blain Fairbairn works in communications at Alberta Health Services.