Objective: Left ventricular noncompaction is a congenital malformation characterized by a myocardium organized into two layers, one compacted and one noncompacted. We aimed to quantify myocardial function, perfusion, and delayed enhancement using MRI in patients with left-ventricular noncompaction and to compare these results with those of normal patients.
Material and methods: We included 12 patients with a myocardial noncompaction / compaction ratio>2.3 at end-diastole in at least one segment apart from the apex and 12 healthy subjects matched for age and sex. We calculated the end-diastolic and end-systolic volumes, stroke volume, ejection fraction, cardiac output, myocardial volume and mass, end-diastolic thickness, and left-ventricular wall thickening and motion. From the delayed enhancement images, we obtained the volume and percentage of hyperenhanced myocardium. Student's t test was used to compare groups.
Results: We observed a statistically significant increase in end-diastolic and end-systolic volumes in patients with left-ventricular noncompaction, as well as decreased ejection fraction, wall motion, and relative maximum upslope in segments 4, 9, and 10. No significant differences were found in delayed hyperenhancement.
Conclusion: MRI quantification revealed decreased systolic cardiac function and decreased perfusion (lower relative maximum upslope) in the lower segments in patients with noncompaction.