A big acquisition decades ago almost broke Boston Scientific. Its CEO says this time is different.

Boston Scientific’s last mega-deal didn’t go so well.

The medtech company with a large Minnesota presence acquired Arden Hills’ Guidant for $27 billion in 2006. This triggered years of legal challenges and deflated financial results.

CEO Mike Mahoney said Jan. 16 that this year’s planned blockbuster purchase of Penumbra, announced the day before for $14.5 billion in cash and stock, “couldn’t be more different.”

“Over the last 14 years, we’ve done about 50 acquisitions of varying sizes, and our team is very good at integrating companies,” Mahoney said in the interview.

The acquisition, which Boston Scientific expects to close sometime this year, adds to the company’s cardiovascular portfolio and provides it something lost in the years following the Guidant acquisition: a solid portfolio of neurovascular devices that treat problems in the blood vessels in the brain.

Penumbra, Mahoney said, provides Boston Scientific a suite of “life-saving, life-changing procedures” treating maladies such as stroke-causing blood clots in the brain and pulmonary embolism clots in the lungs.

The deal, which adds a division to Boston Scientific, is a big change for the company at a time when its explosive stock growth has cooled. While shares dropped nearly 6% in the days after the deal was announced, analysts are optimistic that it can fuel growth.

Boston Scientific and Penumbra kept the deal under wraps throughout the negotiations.

J.P. Morgan analyst Robbie Marcus joked during an investor call Thursday that the two companies’ chief executives could become actors because they “did an excellent job making sure nobody knew about the deal, including with a Penumbra dinner” during a recent health care conference.

Mahoney said he kept talks “as quiet as possible” because a leak could have jeopardized the deal. While Boston Scientific has bought a handful of companies for more than $1 billion in recent years, the Penumbra acquisition would be the first to stretch above $10 billion since the Guidant deal.

The company agreed to pay the $14.5 billion using 73% cash and and 27% stock, the Stifel analysts said. Mahoney said the company’s balance sheet is strong enough to fund Penumbra.

Conditions were different in 2006. Mahoney said Boston Scientific was financially weaker and inexperienced at executing acquisitions when it bought Guidant, which it purchased after a bidding war with Johnson & Johnson. Needing cash, it sold its neurovascular division to Stryker in early 2011 for $1.5 billion.

Mahoney said he has always liked the neurovascular market, as it falls right in line with the company’s portfolio. Neurovascular procedures fix issues affecting nerves, blood vessels and the brain. Boston Scientific already has businesses treating brain conditions, as well as heart and blood maladies — the latter division is largely Minnesota-based.

Boston Scientific has a stronger global footprint than Penumbra, the CEO said, allowing it to scale the business in Europe, China, Japan and the Middle East.

J.P. Morgan analysts, led by Marcus, agreed in an investor note that the deal allows Penumbra’s portfolio to “globalize.” They added that it gives Boston Scientific access to fast-growing markets and the ability to sell complementary products together.

Mahoney said: “They’re in different markets ... but there’s complementary products around them.”

The J.P. Morgan analysts said the deal may make Boston Scientific’s long-range plan of sustained organic sales growth of 10% and up “more achievable and much more durable.”

Penumbra expects 2025 revenue of roughly $1.4 billion, growing by more than 17% compared with 2024. Boston Scientific expects the deal price to slightly dilute profits in the first full year following its close, and then become neutral to slightly beneficial in the second year and more beneficial after that.