...NEW YORK (S&P Global Ratings) Feb. 21, 2019--S&P Global Ratings today assigned its '###-' issue-level rating to Marlborough, Mass.-based medical device manufacturer Boston Scientific Corp.'s proposed $4.3 billion senior unsecured note offering, which the company will issue in multiple tranches. It will use around $1.85 billion of the proceeds to partially fund the BTG Plc acquisition, $1 billion to refinance the term loan maturing in 2019, and $1.45 billion to refinance two bond issues maturing in 2020. Our '###-' issuer credit rating on the company reflects our expectation that Boston Scientific will generally maintain adjusted debt leverage of less than 3.5x in 2020 and beyond, despite a temporary increase in 2019 leverage to 3.7x pro forma for the recent BTG acquisition. This is supported by our belief that the company's annual free operating cash flow will improve to around $2 billion in 2019-2020, reflecting continued strong EBITDA growth and limited further litigation and tax settlement...