St. Jude Medical has received a warning letter from the Food and Drug Administration citing manufacturing "non-conformities" at the Atlanta plant where it makes one of its most promising devices, pulmonary-artery pressure monitor CardioMEMS.

The FDA warning letter, filed with the Securities and Exchange Commission after market close on Friday, says Little Canada-based device maker St. Jude has been actively addressing the issues discovered by inspectors during a three-week on-site inspection at the Georgia plant in June.

The Sept. 30 warning letter does not raise issues with the safety of the devices and none are being recalled in response to the findings. St. Jude is making monthly progress reports to the FDA, and the plant is expected to continue manufacturing and shipping devices without any impact on customer orders, the securities filing says.

"We want to stress, we take these matters very seriously. And we are working diligently to fully address everything that is outlined in the agency's letter," St. Jude spokeswoman Candace Steele Flippin said Friday, adding that the matter can be resolved without any material impact on St. Jude's financial results.

The FDA letter says the CardioMEMS plant did not meet deadlines to adequately address concerns about items including incorrect serial numbers, defects in the surface coating of devices, validation of sterilization procedures. St Jude has provided the FDA with dates when it will complete its corrective actions and/or effectiveness verifications, which will have to be reinspected by the regulator.

The letter says St. Jude has already addressed some of the inspectors' findings — Steele Flippin said a majority of the findings have been addressed.

CardioMEMS is battery-less, permanently implanted sensor that can sense and transmit blood pressure readings from inside the pulmonary artery. The data is collected by heart-failure patients at home and then transmitted to health care providers who may recommend changes in medication to reduce the likelihood of hospitalization.

The device was approved by the FDA in May 2014, and has no competitor on the market. The device, which has a list price of $25,000, generated $20 million in sales for St. Jude in the second quarter of 2015, up 18 percent from the first quarter. The company expects to see at least $85 million in sales of CardioMEMS this year.

Joe Carlson • 612-673-4779

Twitter: @_JoeCarlson