* Symetis' Acurate devices seen complementary to Boston Scientific's Lotus valve devices
* Deal expected to close in Q2
* Boston Scientific shares were down 1.3 pct premarket (Adds details, analyst comment, shares)
March 30 (Reuters) - Boston Scientific Corp (NYSE:BSX) BSX.N said on Thursday it would buy Swiss medical device maker Symetis SA for $435 million, a deal that will help the U.S. company expand in the European market.
Boston Scientific in February recalled its Lotus valve devices from Europe and other regions following reports of a faulty locking mechanism.
These devices are used in TAVR, a minimally invasive procedure, to replace a narrowed aortic valve that fails to open properly. Acurate systems would complement Boston Scientific's Lotus valve devices, the company said.
The acquisition would allow Boston Scientific to enter into the European market immediately, Evercore ISI analyst Vijay Kumar said in a client note.
Boston Scientific said it expects the Lotus valve devices to return to those markets in the fourth quarter. transaction is a bit of a head scratcher and will likely cause some concern on the Street about Boston's Lotus program, J.P. Morgan analyst Michael Weinstein said.
Weinstein also noted Symetis had $40 million in TAVR sales in Europe last year and over the last few years has seen only limited growth.
Following the deal, Symetis said it had halted its IPO launch, its second attempt to go public.
The company was expecting to raise up to 61.5 million euros ($66 million) and list on the Euronext Paris by March 31. Scientific said it expects the deal to slightly boost results in 2018 on an adjusted basis, and rise thereafter. The deal is expected to close in the second quarter, the company said. in February acquired another privately held German medical device maker Middle Peak Medical to expand its portfolio in structural heart devices.
Shares of Boston Scientific, which bought Neovasc Inc 's NVCN.TO tissue processing technology and facility in December, were down 1.3 percent at $24.40 in light premarket trading on Thursday.
($1 = 0.93 euros)