Tryton Medical has enrolled the first U.S. patient in a pivotal trial to evaluate its side branch stent system for the treatment of coronary artery disease. The randomized, controlled study will compare the use of the Tryton stent in the side branch of a bifurcated artery in conjunction with a standard drug-eluting stent in the main vessel, compared with the use of angioplasty in the side branch with a standard drug-eluting stent in the main vessel, the company says. The Tryton system is marketed in the EU and the Middle East but is approved in the U.S. for investigational use only.