Johnson & Johnson's ( JNJ) Cordis unit said Wednesday that it had received regulatory approval to market its Cypher drug-eluting stent in Japan. The company expects to begin distribution midyear in what it called the "world's second-largest interventional cardiology market." Stents are tiny devices inserted into arteries to keep blood flowing freely and prevent the reclogging of arteries, reducing the risk of heart attacks. Cypher was the first drug-coated stent to be approved for use in the U.S., but now faces competition from Boston Scientifc's ( BSX) Taxus stent, which was approved by the Food and Drug Administration in early March. Both Cypher and Taxus are available in many other overseas markets. Johnson & Johnson recently reached a agreement with medical device maker Guidant ( GDT) to help market Cypher. Johnson & Johnson shares were up 12 cents at $50.54.