After 40 years of making heart valves and other medical devices in Minnesota, St. Jude Medical announced plans Thursday to sell itself to Illinois-based Abbott Laboratories in a blockbuster deal with a price tag eclipsing $30 billion.

Abbott agreed to buy out St. Jude stockholders for $25 billion in cash and stock and assume another $5.7 billion in existing St. Jude debt. Company executives gave no indication that the transition will trigger an outflow of the 3,000 jobs St. Jude has in Minnesota.

"We absolutely recognize the importance of Minnesota as a center of excellence for medical device innovation and talent, and we are focused on our employees and continuing our support of this community," St. Jude Vice President Rachel Ellingson said in an e-mail. "We view the significance of this announcement as a testament to the value that St. Jude Medical and our talented employees have been able to create."

The deal, expected to close by year's end, allows Abbott to quickly broaden its medical device product offerings at a time when hospital purchasing departments are looking to deal with fewer suppliers with greater depth in fast-growing health problems like heart failure. But St. Jude will have to bolster its revenue growth to justify Abbott's purchase price, which may be a challenge since it derives more than one-third of its revenue from slow-growing devices like pacemakers and defibrillators.

Stock analysts praised the deal as strategic for Abbott, even though the company stock fell almost 8 percent. St. Jude stock shot up 25 percent in reaction to the deal news.

"It's long overdue. There's been rumors for years," said St. Jude founder Manny Villafana, who left the company in the 1980s. "The numbers that St. Jude keeps producing are good numbers. So it was a likely target."

St. Jude is a Fortune 500 company that reported $5.5 billion in revenue last year and employs about 18,000 people. About 3,000 employees in Minnesota are divided among the company headquarters in Little Canada and facilities in Roseville, Minnetonka and Plymouth.

The company was founded in 1976 around a revolutionary mechanical heart valve that remains in production today with the same basic design. It grew to become a major global competitor in pacemaker and defibrillator sales, which have matured into slow-growing markets. St. Jude has recently lost ground because of a lack of Food and Drug Administration approval for MRI-compatible heart devices.

St. Jude has sought to expand into faster-growing segments of medical needs, particularly treating heart failure, which Executive Chairman Dan Starks has predicted could become the largest market for medical device technology over the next decade.

St. Jude's $3 billion acquisition of advanced heart-device maker Thoratec last year was the "capstone" of the strategy to dominate the market for devices used at all stages of heart failure. The deal brought St. Jude's annualized revenue to $5.9 billion.

With the St. Jude deal, Abbott said it expects to become a leader in nearly every sector of the cardiovascular device market.

A fact sheet distributed by the company projects that more than 40 percent of Americans will be affected by a cardiovascular disease of some sort by 2030.

Abbott also wants to expand its profile among hospital purchasing officials, to adapt to changes in the broader health care market.

Hospitals "obviously want to work with two or three companies, but not many. And a company that has a much broader product offering has a much larger presence in an account," Abbott CEO Miles White told investors in a conference call Thursday.

Abbott has long been rumored to be interested in acquiring St. Jude.

Last August the Financial Times in London reported that Abbott was considering a $25 billion acquisition offer for St. Jude. Both companies denied the story at the time. In an interview with the Star Tribune last September, then-CEO Starks called the report "a bolt from the blue."

Starks stepped down as CEO Jan. 1 and became executive chairman. On Thursday, White told investors there was "no serious interaction" with St. Jude until "very late" in 2015.

Fast forward to Thursday morning, when the new St. Jude CEO, Michael Rousseau, was quoted in a joint news release with Abbott praising the definitive agreement between the two companies: "Today's announcement is an exciting next chapter for St. Jude Medical," the statement said. "Our combined scale will expand the global reach, competitiveness and impact of our medical device innovation."

The companies pledged to find $500 million in annual pretax synergies by 2020. Abbott Chief Financial Officer Brian Yoor said that would include expanded sales of both companies' products, a more streamlined supply chain and distribution system, and unspecific "efficiencies" in general and administrative spending.

It was not clear that Wall Street saw the same potential, given the 8 percent decline in Abbott's stock value Thursday.

"I think that's just people struggling to see where the synergies are going to come from, especially on the top [revenue] line," said Piper Jaffray analyst Brooks West. "St. Jude has 40 percent exposure to cardiac-rhythm management, and that market is not growing."

Shaye Mandle, chief executive of Minnesota med-tech trade group Medical Alley Association, said that right now the word on the street is not about synergies that lead to job cuts.

"We're not, at least as this point, aware of or expecting as part of this deal any significant changes in workforce or any of those issues here in Minnesota," Mandle said. "I think we're excited about the opportunity to bring the Abbott family into Medical Alley and help to demonstrate how growth opportunities for Abbott, long term, are best suited to be in this community."