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Updated: Jul 29, 2026
15:26
3D Modeling of the Lateral Ventricles and Histological Characterization of Periventricular Tissue in Humans and Mouse
Published on: May 19, 2015
The sequence of regional ventricular motion.
Manel Ballester-Rodés1, Albert Flotats, Francisco Torrent-Guasp
1Department of Medicine, Faculty of Medicine, University of Lleida, Spain. mballesterr@comll.es
Summary
The heart
Area of Science:
- Cardiovascular Physiology
- Cardiac Electrophysiology
- Myocardial Mechanics
Background:
- Traditional view: myocardial electrical activation proceeds from septum to apex, then to ventricular bases.
- Emerging theory: myocardium as a single helical band, with contraction following a base-to-apex pattern.
- This helical model potentially explains observed base motion and ventricular twisting.
Purpose of the Study:
- To investigate the sequence of myocardial mechanical activation.
- To compare electrical activation patterns with mechanical contraction sequences.
- To evaluate the helical myocardial band theory.
Main Methods:
- Utilized temporal Fourier analysis of equilibrium radionucleide angiocardiography.
- Studied regional myocardial mechanical displacement and electro-mechanical activation wavefronts.
- Observed myocardial motion sequences in 29 healthy individuals.
Main Results:
- Mechanical activation initiates at the base of the heart (right then left ventricle).
- Mechanical movement subsequently progresses towards the apex and septum.
- Findings support the proposed helical myocardial activation model.
Conclusions:
- Electrical activation follows a septum-apex-base sequence.
- Myocardial mechanical activation occurs in a base-to-apex direction.
- Anisotropic propagation of electromechanical stimulus likely underlies this base-to-apex mechanical sequence.
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