Abbott Laboratories expects that more than 1 million diabetics worldwide will be using its new FreeStyle Libre continuous glucose monitor (CGM) before the year is out, and the company is investing heavily to expand production capacity for the mass-market medical device.

In an earnings call Wednesday to announce better than expected second quarter results, Abbott chief executive Miles White said the Illinois-based health care products company is on track to exceed its goal of at least $90 million in U.S. sales for the Libre in 2018.

The device was approved in the U.S. last fall as the nation's first sensor that can continuously monitor adult blood sugar without requiring a blood sample for calibration.

White said a key part of the device's appeal its "economically accessible" price for patients and insurers. In a market in which other devices for insulin-dependent patients can cost thousands of dollars, the FreeStyle Libre sensor carries a $36 price tag for 10 days' use in the U.S., meaning it costs about $1,300 a year at list prices.

"It's got so much potential," White told the analysts on the call. "A lot of times, whether it is a pharmaceutical or a medical device, they can be expensive in the healthcare system ... because the numbers of patients may not be that great. And yet, there's a lot of diabetics in the world, including me."

Abbott competes with Minnesota's Medtronic for diabetes-device sales, though the two companies have dissimilar offerings. Medtronic is heavily invested in sophisticated insulin pumps, but only recently entered the market for stand-alone CGMs; Abbott has a strong foothold in the burgeoning CGM market, while it is partnering with California's Bigfoot Biomedical to develop next-generation insulin-delivery devices that are still in clinical testing.

The 34 percent quarterly organic growth in Abbott's $470 million diabetes care unit helped offset losses elsewhere in its medical device portfolio, particularly with the heart-rhythm devices that Abbott acquired last year when it bought Minnesota pacemaker maker St. Jude Medical, earnings figures released Wednesday show.

In particular, sales of St. Jude devices to hearts beating in proper rhythm saw a 4 percent decline in the second quarter, to an organic $543 million. (Abbott's organic sales figures exclude the impact of international currency fluctuations and sales of products recently acquired or divested.)

White attributed the slowdown in sales, compared to the same quarter last year, to an uptick in early replacements that happened under St. Jude's watch.

Shortly before Abbott acquired St. Jude in January 2017, St. Jude announced that many of its implantable heart defibrillators were vulnerable to short circuits that could unexpectedly drain device batteries. Although the FDA did not recommend "prophylactic" replacement of devices without signs of battery depletion, White said Wednesday that "a lot" of devices ended up being replaced early.

"They pulled forward a lot of replacements to replace those batteries, so you see fewer replacements now," White said.

Stock analysts with Leerink Partners said in a note to investors that the overall market for heart devices may have "taken a step down" during the second quarter because of competitive pricing pressure, now that Abbott, Medtronic and devicemaker Boston Scientific all offer MRI-approved versions of the devices. The analysts also noted that their recent survey of hospital administrators found no seasonal uptick in heart-surgery volumes, which could affect sales.

Meanwhile, sales of St. Jude heart-assist devices to treat major heart failure grew by just 1 percent to $163 million. Although the company's implantable HeartMate 3 blood pump was the subject of a Class I recall during the second quarter, White said the company just needs a wider approval from the FDA to expand sales. Currently the device is approved as a short-term bridge to heart transplant, but not as a long-term "destination" therapy.

"We just need a destination-therapy claim and I think we're going to be in great shape," he said.

Following the roughly $25 billion acquisition of St. Jude, medical devices became the largest of Abbott's four divisions, with nearly $3 billion in sales accounting for more than a third of the company's total sales in the second quarter.

Overall Abbott beat Wall Street earnings forecasts by 2 cents per share in the second quarter. Across all of its product divisions, the global seller of health care devices and nutritional products reported $1.3 billion in earnings from continuing operations on $7.8 billion in revenue in the quarter. Earnings from operations were up 18 percent.

The company added several cents to its earnings per share outlook for the remainder of the year, with adjusted diluted EPS for the full year now expected in the range of $2.85 to $2.91.

"This was another very good quarter as we execute on our strategic priorities," White said Wednesday. "Despite recent currency shifts, we are raising our outlook even higher."

For the third quarter, Abbott is expecting adjusted diluted earnings per share in a range of 73 cents to 75 cents.

Abbott stock climbed nearly 3.1 percent on Wednesday, closing at $64.75.