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Updated: May 31, 2026
Optocardiography and Electrophysiology Studies of Ex Vivo Langendorff-perfused Hearts
Published on: November 7, 2019
Ventricular repolarization sequences on the epicardium and endocardium. Monophasic action potential mapping in
Ole Kongstad1, Yunlong Xia, Ying Liu
1Department of Arrhythmias, Skåne University Hospital, Lund University, Lund, Sweden.
Unlabelled:
To investigate repolarization sequence, monophasic action potentials were recorded from a mean of 153 ± 54 left and right ventricular epicardial and endocardial sites in 10 pigs using the CARTO mapping system (Biosense Webster, Waterloo, Belgium). The activation time and end-of-repolarization (EOR) time were measured and 3-dimensional maps of activation and repolarization sequences constructed.
Results:
In 8 of 9 pigs, both the activation and EOR times appeared first in the septum and last in the latero-basal areas on the endocardium, not on the epicardium. The EOR followed the activation sequence, both on the epicardium (in 8/9 pigs) and endocardium (in 8/8 pigs). The maximal EOR differences were 84 ± 20 ms, whereas the local EOR differences between paired sites against each other on the left ventricular epicardium and endocardium were 11 ± 9 ms in the apex and 12 ± 12 ms in the anterior wall.
Conclusion:
The EOR follows the activation sequence both on the epicardium and endocardium. The apico-basal gradients are predominant repolarization gradients, as compared with the epicardial-endocardial gradients.
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