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Updated: May 28, 2026

Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System
Published on: May 22, 2018
Atrial repolarization: its impact on electrocardiography
1Department of Medicine, Section of Cardiology, University o f Chicago, IL, USA. rchilder@medicine.bsd.uchicago.edu
Abstract:
The repolarizing T(a) wave of normal sinus rhythm is not fully visible unless there is a long P-R interval or complete atrioventicular block. Even with the latter, it is often of unseeably low voltage. It can powerfully influence inferior lead ST deviation in the stress test. The T(a) of inverted or retrograde P waves is of higher voltage than that of sinus rhythm and can simulate inferior injury. Evidence of specialized internodal tracts resides in 2 specific atrial action potential properties: resistance to gross hyperkalemia and supernormality. The T(a) wave figures essentially in the diagnosis of acute atrial infarction.
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