Yesterday the Centers for Disease Control and Prevention (CDC) warned patients and providers of a risk of infection from devices used in open-heart surgery.

The concern comes after heater-cooler devices manufactured by LivaNova PLC, of London, were found to be contaminated with harmful bacteria during manufacturing.

Devices commonly used

The CDC said about 60% of the 250,000 heart bypass surgeries performed in the United States each year involve these heater-cooler devices, which keep circulating blood and organs at appropriate temperatures during the procedures. If the devices are contaminated, patients could suffer from infection with Mycobacterium chimaera, which can cause serious illness and even death.

The CDC said anyone who's recently had heart surgery should "seek medical care if they are experiencing symptoms associated with infections, such as night sweats, muscle aches, weight loss, fatigue, or unexplained fever."

The CDC said that in a hospital where one contamination has been identified, the risk to other patients was between 1 in 100 and 1 in 1,000. And it can take months to develop symptoms of M chimaera infection, and many of the symptoms are non-specific, meaning missed diagnoses are likely, according to the agency.

M chimaera is usually found in water and soil, and the bacterium can live in the water circuit of the device that's used to regulate the body temperature of a patient. Though the water doesn't come in direct contact with the patient, the bacteria can be introduced through an aerosol spray that's released by the device's exhaust vent.

"It's important for clinicians and their patients to be aware of this risk so that patients can be evaluated and treated quickly," said Michael Bell, MD, deputy director of the CDC's Division of Healthcare Quality Promotion. "Hospitals should check to see which type of heater-coolers are in use, ensure that they're maintained according to the latest manufacturer instructions, and alert affected patients and the clinicians who care for them."

FDA issues alert

The Food & Drug Administration (FDA) released its own statement on the coolers, saying that hospitals with reports of M chimaera should stop using contaminated devices, and that any tubing or parts should be promptly discarded and replaced.

In the spring of 2015, investigators in Switzerland found invasive infection with M chimaera in a cluster of six patients later identified as having open-heart surgery where surgeons used the Stockert 3T heater-cooler devices. A similar cluster appeared in Pennsylvania in July 2015. A recent report of Stockert 3T heater-cooler devices in Germany pointed toward contamination in three separate countries.