BACKGROUND: It is unclear whether the Tpeak-Tend interval is an index of the transmural or the total dispersion of repolarization. METHODS: We examined the Tpeak-Tend interval using a computer model of the rabbit heart ventricles based on experimentally measured transmural, apicobasal, and interventricular gradients of action potential duration. RESULTS: Experimentally measured activation-recovery intervals increased from apex to base, from the left ventricle to the right ventricle, and in the apical portion of the left ventricle from epicardium to endocardium and from the right side of septum to the left side. The simulated Tpeak corresponded to the earliest end of repolarization, whereas the Tend corresponded to the latest end of repolarization. The different components of the global repolarization dispersion were discerned by simulation. CONCLUSIONS: The Tpeak-Tend interval corresponds to the global dispersion of repolarization with distinct contributions of the apicobasal and transmural action potential duration gradients and apicobasal difference in activation times.
BACKGROUND: It is unclear whether the Tpeak-Tend interval is an index of the transmural or the total dispersion of repolarization. METHODS: We examined the Tpeak-Tend interval using a computer model of the rabbit heart ventricles based on experimentally measured transmural, apicobasal, and interventricular gradients of action potential duration. RESULTS: Experimentally measured activation-recovery intervals increased from apex to base, from the left ventricle to the right ventricle, and in the apical portion of the left ventricle from epicardium to endocardium and from the right side of septum to the left side. The simulated Tpeak corresponded to the earliest end of repolarization, whereas the Tend corresponded to the latest end of repolarization. The different components of the global repolarization dispersion were discerned by simulation. CONCLUSIONS: The Tpeak-Tend interval corresponds to the global dispersion of repolarization with distinct contributions of the apicobasal and transmural action potential duration gradients and apicobasal difference in activation times.
Authors: Olesya G Bernikova; Alena S Tsvetkova; Alexey O Ovechkin; Marina M Demidova; Jan E Azarov; Pyotr G Platonov Journal: Int J Mol Sci Date: 2022-10-05 Impact factor: 6.208