Calgary doctors say they posted a Canadian medical first this week when they used a less invasive procedure to place a net around a woman's heart.

Surgeons used X-ray technology to wrap an elastic silicone-coated Nitinol or nickel titanium mesh net around Maggie Thiessen's heart on Wednesday at Foothills Medical Centre.

The experimental procedure is used to stop the heart from enlarging and temper symptoms of heart failure, Calgary Health Region said Friday.

"It's malleable and it's temperature sensitive," Dr. Jehangir Appoo, one of the cardiac surgeons involved in the operation, said of the HeartNet.

"It fits snugly around the heart and prevents the heart from dilating. [It] creates a more efficient heart cycle and this net … would expand and come back with every single beat of the heart."

Thiessen, of Calgary, was suffering shortness of breath after brief walks — a symptom of potential heart failure and a condition she shares with nearly half a million Canadians.

"I am looking forward to moving around without feeling out of breath all the time," she said in a statement, according to the Calgary Herald newspaper.

"It's a procedure where we have very good background data suggesting this should work but we're in the process of proving it does," Dr. Debra Isaac, the Calgary cardiologist who is leading an international study on the surgery, told the Herald.

"This promotes heart remodelling, promotes it being smaller and energy efficient."

Instead of making an incision down the centre of the patient's chest and putting her on a heart-lung machine, the cardiac team used X-ray vision to guide them through a smaller incision. Appoo said more operations like this could follow depending on how Thiessen recuperates.

Foothills is the first hospital in Canada to research HeartNet's effectiveness. Surgeons in the U.S. are also conducting clinical trials.