Myocardial Recovery in Patients With Systolic Heart Failure and Autoantibodies Against β1-Adrenergic Receptors
Yuji Nagatomo, Dennis M. McNamara, Jeffrey D. Alexis, Leslie T. Cooper, G. William Dec, Daniel F. Pauly, Richard Sheppard, Randall C. Starling, W.H. Wilson Tang, IMAC-2 Investigators, Dennis M. McNamara, Karen Janosko, Charles McTiernan, Barry London, Karen Hanley-Yanez, John Gorcsan, Hidekazu Tanaka, Mathew Suffoletto, Randall C. Starling, Cynthia Oblak, Leslie T. Cooper, Annette McNallan, LuAnne Koenig, Paul Mather, Natalie Pierson, Sharon Rubin, Yanique Bell, Alicia Ervin, John Boehmer, Patricia Frey, Jeffrey Alexis, Janice Schrack, Pam LaDuke, Guillermo Torre-Amione, Jeannie Arredondo, Daniel F. Pauly, Pamela C. Smith, Richard Sheppard, Stephanie Fuoco, Ilan S. Wittstein, Elayne Breton, Vinay Thohan, Deborah Wesley, G. William Dec, Diane Cocca-Spofford, David W. Markham, Lynn Fernandez, Colleen Debes, Mark J. Zucker, Laura Adams, Peter Liu, Judith Renton, Jagat Narula, Byron Allen and Elizabeth Westberg
Autoantibodies Specifically Against β1ARs in Cardiomyopathy
(A) In investigating the role of β1-adrenergic receptor autoantibodies (β1AR-AAbs) belonging to the immunoglobulin G3 (IgG3) subclass in patients with recent-onset cardiomyopathy, we found no significant difference in left ventricular ejection fraction (LVEF) at baseline and 6 months based on presence or absence of total immunoglobulin G (IgG). (B) However, when the population was divided on the basis of IgG3 positivity, a significant difference in LVEF emerged at 6 months. (C) When the population was further divided into patients who were β1AR-AAb negative, non–IgG3-β1AR-AAb positive, and IgG3-β1AR-AAb positive, the IgG3 groups demonstrated significantly higher LVEF compared with each of the other cohorts.