** U.S.-listed shares of Canadian medical device maker soar 53.7 pct to $3.75 premarket after FDA grants Neovasc Reducer, used to treat refractory angina, breakthrough device status
** NVCN is top pct gainer among U.S. stocks and if gains hold, stock is on pace for its best day in nearly 2 years
** Refractory angina is a chronic condition characterized by debilitating chest pain, estimated to affect 600,000-1.8 mln Americans
** On Oct. 3, data showed the first U.S. patient implanted with the Reducer was able to walk several miles, reduce usage of nitroglycerine for chest pains, experience lesser chest discomfort
** Breakthrough device status is usually granted to speed up review of a device that can potentially treat life-threatening conditions
** The device is not currently approved for commercial sale in the U.S.
** Up to Tuesday’s close, stock has lost ~96 pct of its value this year (Reporting by Amy Caren Daniel in Bengaluru)