Left ventricular non-compaction: insights from cardiovascular magnetic resonance imaging.
OBJECTIVE
We aimed to test the diagnostic accuracy of cardiovascular magnetic resonance (CMR) imaging in distinguishing pathological left ventricular non-compaction (LVNC) from lesser degrees of trabecular layering seen in healthy volunteers and, in those with cardiomyopathies and concentric left ventricular hypertrophy, potential differential diagnoses. We hypothesized that pathological trabeculation could be distinguished by determining the ratio of non-compacted to compacted myocardium (NC/C ratio).


BACKGROUND
Left ventricular non-compaction is characterized by a non-compacted myocardial layer in the left ventricle. Cardiovascular magnetic resonance images this layer with unprecedented quality, particularly in the ventricular apex, where echocardiography has inherent difficulties.


METHODS
We analyzed magnetic resonance cine images, using the 17-segment model in 45 healthy volunteers, 25 athletes, 39 patients with hypertrophic cardiomyopathy and 14 with dilated cardiomyopathy, 17 with hypertensive heart disease, and 30 with aortic stenosis, as well as images from 7 patients previously diagnosed with LVNC whose diagnoses were supported by additional features.


RESULTS
Areas of non-compaction were common and occurred more frequently in all groups studied in apical and lateral, rather than in basal or septal, segments. A NC/C ratio of >2.3 in diastole distinguished pathological non-compaction, with values for sensitivity, specificity, and positive and negative predictions of 86%, 99%, 75%, and 99%, respectively.


CONCLUSIONS
Left ventricular non-compaction is diagnosed accurately with CMR using the NC/C ratio in diastole.
University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom.
Steffen E
SE
Petersen
Joseph B
JB
Selvanayagam
Frank
F
Wiesmann
Matthew D
MD
Robson
Jane M
JM
Francis
Robert H
RH
Anderson
Hugh
H
Watkins
Stefan
S
Neubauer
D000293:Adolescent; D000328:Adult; D001024:Aortic Valve Stenosis / Q000473:pathology*; D009202:Cardiomyopathies / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006352:Heart Ventricles / Q000473:pathology*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012307:Risk Factors