Medical device maker Medtronic announced two regulatory approvals on Monday, including a new way that patients with diabetes can use its latest blood-glucose monitor and a narrower stent that fits inside some of the smallest blood vessels near the heart.

For diabetics, the U.S. Food and Drug Administration is now allowing the Minnesota-run company to market its Guardian Sensor 3 to be worn on the upper arm. Previously the device was only recommended to be worn on the abdomen to measure the amount of insulin in a patient's blood stream.

Type 1 diabetes, formerly known as "juvenile diabetes," is the more severe form of the condition, in which a person's immune system attacks the cells in their pancreas that produce the insulin needed to convert blood sugar into energy. Having blood sugar levels that are too high or too low can increase the risk of stroke, blood-vessel disease and nerve damage.

The Guardian Sensor 3 is approved for use with Medtronic's popular MiniMed 670G insulin pump, which is the only insulin pump on the market that is allowed to automatically adjust the amount of medication it delivers based on readings from a glucose sensor. The pump is intended for people with type 1 diabetes who are at least 14 years old.

Also Monday, Medtronic announced FDA approval for a drug-eluting heart stent called the Resolute Onyx 2.0 mm. The device is about as wide as the edge of a nickel and is the smallest stent on the market, according to the company. It joins a line of Resolute Onyx stents that can be used to treat coronary blood-vessel blockages from the smallest to the largest.

A stent is a tiny metal mesh tube used to prop open a narrowed or blocked blood vessel. Many modern stents are coated with anti-inflammatory drugs that "elute," or release, into the blood vessel over time to prevent reclosure.

The 2-mm Resolute Onyx version is intended to treat blockages in vessels so narrow that they were previously thought to be untreatable. A Medtronic news release cited a 1999 study that estimated that about 65 percent of smaller vessels are in "critical locations in the heart," making them "significant" blockages to treat.

Once deployed through a minimally invasive procedure, the 2-mm stent can be expanded up to 3.25 mm, making it an option to treat blocks in difficult-to-treat areas of the heart, the company said.

Joe Carlson • 612-673-4779