[1] Northwestern Univ, Feinberg Sch Med, Chicago, IL 60611 USA
[2] Univ Gothenburg, Dept Cardiol, Gothenburg, Sweden
[3] Fdn IRCCS Policlin San Matteo, Div Cardiol, Pavia, Italy
[4] Univ Paris, Lariboisiere Hosp, Dept Anesthesiol & Crit Care Med, F-75252 Paris, France
[5] Univ N Carolina, Div Cardiol, Chapel Hill, NC USA
[6] Univ Calif Los Angeles, David Geffen Sch Med, UCLA Med Ctr, Ahmanson UCLA Cardiomyopathy Ctr, Los Angeles, CA USA
[7] European Hosp, Dept Cardiovasc Sci, Lab Intervent Cardiol, Rome, Italy