Evaluation of the extent of left ventricular trabeculations and association with imaging findings and clinical outcomes in pediatric patients with possible left ventricular noncompaction cardiomyopathy

Background Left ventricular noncompaction cardiomyopathy (LVNC) is characterized by prominent trabeculations in the left ventricle and has been associated with adverse outcomes; yet, there is difficulty in discerning pathologic trabeculations from normal variation. Objectives This study sought to test the hypothesis that a ratio of noncompacted to compacted (NC:C) myocardium of >2.3 in diastole by cardiac magnetic resonance imaging (CMR) is associated with adverse clinical outcome and imaging findings in children and young adults referred for CMR to assess for presence of LVNC cardiomyopathy. Methods A retrospective cohort study was performed of patients who were referred for CMR at our center for suspected LVNC between 1/1/11 and 12/31/21. An NC:C ratio was calculated for each CMR, and patients were classified as CMR+ or CMR− using a NC:C cutoff of >2.3. Demographic, electrocardiographic, echocardiographic, CMR, and clinical outcome data were compared. Results Fifty-one patients were identified, with 30 (59 %) being CMR+. Patients were 12.9 ± 4.7 years old at the time of CMR and followed for a median of 1.7 (IQR 0.1–4.4) years. Baseline characteristics were similar between the CMR+ and CMR− groups. Of the cohort, 1/51 (2 %), who was CMR−, had a stroke and 5/51 (10 %) experienced significant arrhythmia or ectopy with no significant difference between the groups. There was no mortality, transplant, or mechanical support. LV systolic dysfunction was noted in 8/51 (16 %) of patients by CMR with no significant difference between the CMR+ and CMR− groups. There was no correlation between the NC:C ratio and left or right ventricular systolic function by CMR. Conclusion NC:C ratio, as measured by CMR, alone may be an inadequate marker of pathologic left ventricular trabeculations in children and young adults.