(Sharecast News) - Shares in specialist healthcare company BTG rocketed on Tuesday as it agreed to be bought by US-based Boston Scientific for £3.3bn.Under the terms of the deal, which has been approved by the boards of directors of both companies, BTG shareholders would receive 840p in cash.BTG chief executive Louise Makin said:"Boston Scientific shares our commitment to transforming patient care, and has a sustained track record of innovation, clinical expertise and global commercial capabilities."Boston Scientific chairman and chief executive Mike Mahoney said: "The acquisition of BTG and its rapidly growing peripheral interventional portfolio is an exciting extension of our category leadership strategy that will augment our capabilities in important areas of unmet need such as cancer and pulmonary embolism."We are confident that the addition of these therapies to our portfolio will ultimately advance patient care in ways that could not be realised by either company alone, while also allowing us to realize substantial revenue and cost synergies and provide a strong return for investors."The transaction is expected to close in the first half of next year.At 0915 GMT, BTG shares were up 34% to 825p.