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Updated: Jan 31, 2026
09:05
Transthoracic Speckle Tracking Echocardiography for the Quantitative Assessment of Left Ventricular Myocardial Deformation
Published on: October 20, 2016
20.1K
Regional Mechanical Changes Assessed by 2D Speckle-Tracking Longitudinal Strain do not Parallel Electrical
Suran Maria-Claudia-Berenice1, Margulescu Andrei-Dumitru1, Bruja Ramona2
1University of Medicine and Pharmacy "Carol Davila" Bucharest, Bucharest, Romania.
Maedica
|December 21, 2018
Summary
Cardiac memory (CM) induced by ventricular pacing shows electrical changes but no significant regional mechanical alterations in left ventricular segments. Time-to-peak longitudinal strain increased, but did not correlate with electrical CM resolution.
Area of Science:
- Cardiology
- Cardiac Electrophysiology
- Cardiovascular Imaging
Background:
- Cardiac memory (CM) involves persistent T-wave changes after abnormal ventricular activation.
- Animal studies suggest CM is linked to prolonged action potential duration and myocardial strain.
Purpose of the Study:
- To investigate if CM induced by ventricular pacing in humans is associated with regional mechanical changes.
- To assess left ventricular (LV) longitudinal strain (LS) and time-to-peak LS (TTP-LS) using 2D-speckle tracking echocardiography (2DSE).
Main Methods:
- 20 patients with DDD pacemakers underwent ECG and 2DSE before, during, and after pacing-induced CM.
- LV ejection fraction, diastolic function, peak LS, and TTP-LS were measured in earliest and latest activated segments.
Main Results:
- All patients exhibited electrical CM, which resolved after pacing cessation.
- LV global systolic and diastolic functions remained unchanged.
- Time-to-peak LS increased during pacing but did not normalize with CM resolution; peak LS did not change.
Conclusions:
- Regional mechanical changes assessed by 2DSE longitudinal strain do not appear to directly correlate with electrical cardiac memory.
- Pacing-induced CM in humans may involve distinct electrical and mechanical remodeling processes.
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