ARCA Biopharma ($ABIO) is planning a Phase IIb/III trial of Gencaro, an investigational atrial fibrillation drug, and Medtronic ($MDT) has signed on to outfit each patient with an implanted CRT-D, measuring the therapy's effect. ARCA is starting with 200 patients in Phase IIb before, depending on results, rolling the study into a 420-patient Phase III trial. More