A trial of more than 1,000 patients with implantable cardioverter defibrillators found that the drug ranolazine (used to treat chest pain; brand name Ranexa (R)) was safe but didn't decrease the likelihood of the first occurrence of ventricular arrhythmias or death in this high-risk population. The drug did lower the risk for recurrent ventricular tachycardia by 30 percent, suggesting it could be a treatment option for this very sick population for which there are limited therapies.