AHA Journals, Author Interviews, Connective Tissue Disease, Heart Disease, NYU/NYMC / 08.07.2015
Autoimmune Antibodies Can Lead To EKG Abnormalities and Ventricular Arrhythmias
MedicalResearch.com Interview with:
Mohamed Boutjdir, PhD, FAHA
Director of the Cardiovascular Research Program
VA New York Harbor Healthcare System
Professor, Depts of Medicine, Cell Biology and Pharmacology, State University of New York Downstate Medical Center and
NYU School of Medicine, New York, NY
Medical Research: What is the background for this study? What are the main findings?
Dr. Boutjdir: Patients with autoimmune diseases including Sjogren’s syndrome, systemic lupus erythematosus and other connective tissue diseases who are seropositive for anti-SSA/Ro antibodies may present with corrected QTc prolongation on the surface ECG. This QTc prolongation can be arrhythmogenic and lead to Torsades de Pointes fatal arrhythmia.
In our study, we established for the first time an animal model for this autoimmune associated QTc prolongation that is reminiscent of the clinical long QT2 syndrome. We also demonstrated the functional and molecular mechanisms by which the presence of the anti-SSA/Ro antibodies causes QTc prolongation by a direct cross-reactivity and then block of the hERG channel (Human ether-a-go-go-related gene). This hERG channel is responsible for cardiac repolarization and its inhibition causes QTc prolongation. We were able to pinpoint to the target epitope at the extracellular pore forming loop between segment 5 and segment 6 of the hERG channel.



















