Following positive news from trials that could significantly expand demand for its heart valves, Edwards Lifesciences (NYSE:EW) shares sky-rocketed. The trials show that the company’s transcatheter heart valves work as well (and sometimes better) than traditional open heart surgery in patients at intermediate risk. The study could lead to Edwards Lifesciences heart valves becoming more widely used, giving it a valuable edge in its battle for market share with medtech Goliath Medtronic (NYSE:MDT).