Which is the most likely abnormality represented in these images from a 48-year-old man with...

The echocardiographic images show prominent trabeculations and deep intertrabecular recesses communicating with the left ventricular cavity, best seen on contrast-enhanced images. This finding is characteristic of left ventricular noncompaction (LVNC), a cardiomyopathy resulting from arrested myocardial compaction during embryogenesis.

LVNC is diagnosed by visualizing a two-layered myocardium with a thin compacted epicardial layer and a thicker noncompacted endocardial layer with deep trabecular recesses. The use of contrast echocardiography enhances endocardial border delineation and recess visualization, increasing diagnostic accuracy.

Loeffler syndrome (hypereosinophilic cardiomyopathy) often shows endomyocardial fibrosis and restrictive physiology but not prominent trabeculations. Hypertrophic cardiomyopathy shows asymmetric septal hypertrophy without deep recesses. Ischemic cardiomyopathy shows wall motion abnormalities but not characteristic trabecular patterns.

These diagnostic criteria and imaging features are well documented in the "Textbook of Clinical Echocardiography" and ASE guidelines on cardiomyopathies and use of contrast echo【16:Textbook of Clinical Echocardiography, 6e†Chapter on LV Noncompaction】【12:ASE Contrast Echocardiography Guidelines†p.180-190】.