Officials with Alberta Health Services said they were working to notify thousands of former open-heart surgery patients, over the potential risk they could have been exposed to bacteria during surgery.

AHS said two agencies in the United States: the Federal Drug Administration (FDA) and Centers for Disease Control (CDC), and Health Canada have reported a potential risk for mycobacterium chimaera infection in connection with certain heater-cooler units.

The units are used to warm and cool blood during open-heart surgery for adult and pediatric patients, there is a small risk the bacteria can form in the device's water vapour, and could blow contaminants into a patient's open chest.

Those units have been used, and are still in use at two facilities in Edmonton: the Mazankowski Alberta Heart Institute, and the Stollery Children’s Hospital. AHS said the unit has also been used at the Foothills Medical Centre in Calgary.

“We are releasing this information proactively to share details about the potential risk of exposure to M. chimaera bacteria as well as to reassure patients and families that there is an extremely low risk of infection in those who may have been exposed,” Dr. Mark Joffe, AHS Senior Medical Director, Infection, Prevention and Control, said in a statement. “No infections have been identified to date in any AHS cardiac patients.”

Joffe said workers follow manufacturer instructions to clean and maintain the machines, and more safety measures have been added.

AHS said M. chimaera infections can’t be spread person-to-person, and infections grow slowly and could take months or even years to develop.

Symptoms can be subtle, but officials said they will usually progress over a number of weeks and could include:

  • Fever
  • Unexplained, persistent and profuse night sweats
  • Weight loss
  • Muscle aches
  • Fatigue
  • Redness, heat or pus at the surgical incision site

Officials said anyone who may have been exposed and could be experiencing symptoms should seek medical attention immediately. No infections have been reported in Alberta. Two patients in Quebec are being investigated for possible infection, and two dozen patients in the U.S. have been found to have it

In the coming days, AHS said notifications will be mailed to physicians and discharged open-heart surgery patients who could have been exposed. The notification will also include adults and parents or guardians of pediatric patients.

Patients who have had open heart surgery from January 1, 2012 to now will be notified by AHS.

Individuals seeking more information can contact Health Link at 811.