[1] Stanford Univ, Sch Med, Dept Cardiothorac Surg, Stanford, CA USA
[2] Stanford Univ, Sch Med, Dept Bioengn, Stanford, CA USA
[3] Stanford Univ, Dept Stanford Cardiovasc Inst, Sch Med, Stanford, CA USA
[4] Stanford Univ, Falk Cardiovasc Res Ctr, Sch Med, Dept Cardiothorac Surg, 870 Quarry Rd Ext, Palo Alto, CA 94305 USA