Related Experiment Video
Updated: Mar 13, 2026
Assessment of Right Ventricular Structure and Function in Mouse Model of Pulmonary Artery Constriction by Transthoracic Echocardiography
Published on: February 3, 2014
Pneumatic Distension of Ventricular Mural Architecture Validated Histologically
M C Burg1, P Lunkenheimer2, P Niederer3
1Department of Clinical Radiology, University Hospital Münster, Germany.
Insights
Pneumatic distension reveals complex, heterogeneous cardiomyocyte aggregation in heart walls, challenging uniform tangential models. This organized structure, with regional variations, influences global ventricular function.
Area of Science:
- Cardiovascular research
- Cardiac anatomy
- Biomedical imaging
Background:
- Ongoing debate regarding cardiomyocyte aggregation patterns in ventricular walls.
- Understanding cardiac architecture is crucial for comprehending heart function.
Purpose of the Study:
- To investigate the aggregation patterns of cardiomyocytes within the ventricular walls.
- To challenge existing assumptions about uniform cardiomyocyte arrangement.
Main Methods:
- Pneumatic distension of porcine coronary arteries to exaggerate cardiomyocyte gaps.
- Computed tomography (CT) imaging to analyze mural architecture and cardiomyocyte angulation.
- Histological validation of CT findings.
Main Results:
- Pneumatic distension elongated ventricular walls without significant thickness changes.
- Exaggerated spaces revealed epicardial, central, and endocardial regions with feathered transitions.
- Marked heterogeneity in regional thickness and spiraling cardiomyocyte arrangement from base to apex.
Conclusions:
- Cardiomyocyte aggregation is not uniformly tangential, exhibiting significant regional heterogeneity.
- Aggregated cardiomyocytes form a structured continuum, not extending transmurally in a uniform manner.
- Heterogeneous architecture contributes to global ventricular function through antagonistic forces.
Abstract:
Purpose: There are ongoing arguments as to how cardiomyocytes are aggregated together within the ventricular walls. We used pneumatic distension through the coronary arteries to exaggerate the gaps between the aggregated cardiomyocytes, analyzing the pattern revealed using computed tomography, and validating our findings by histology. Methods: We distended 10 porcine hearts, arresting 4 in diastole by infusion of cardioplegic solutions, and 4 in systole by injection of barium chloride. Mural architecture was revealed by computed tomography, measuring also the angulations of the long chains of cardiomyocytes. We prepared the remaining 2 hearts for histology by perfusion with formaldehyde. Results: Increasing pressures of pneumatic distension elongated the ventricular walls, but produced insignificant changes in mural thickness. The distension exaggerated the spaces between the aggregated cardiomyocytes, compartmenting the walls into epicardial, central, and endocardial regions, with a feathered arrangement of transitions between them. Marked variation was noted in the thicknesses of the parts in the different ventricular segments, with no visible anatomical boundaries between them. Measurements of angulations revealed intruding and extruding populations of cardiomyocytes that deviated from a surface-parallel alignment. Scrolling through the stacks of tomographic images revealed marked spiraling of the aggregated cardiomyocytes when traced from base to apex. Conclusion: Our findings call into question the current assumption that cardiomyocytes are uniformly aggregated together in a tangential fashion. There is marked heterogeneity in the architecture of the different ventricular segments, with the aggregated units never extending in a fully transmural fashion. Key Points: • Pneumographic computed tomography reveals an organized structure of the ventricular walls.• Aggregated cardiomyocytes form a structured continuum, with marked regional heterogeneity.• Global ventricular function results from antagonistic forces generated by aggregated cardiomyocytes. Citation Format: • Burg MC, Lunkenheimer P, Niederer P et al. Pneumatic Distension of Ventricular Mural Architecture Validated Histologically. Fortschr Röntgenstr 2016; 188: 1045 - 1053.
