THE DEVICES: Pacemakers, implantable cardioverter defibrillators (ICDs), stents
WHAT THEY DO: Correct irregular heartbeat and rhythm, prevent artery blockages, and treat early-stage heart failure.
WHO MAKES THEM: Boston Scientific(BSX), Conor Medsystems (CONR), Johnson & Johnson (JNJ, Medtronic (MDT), St. Jude Medical (STJ)