To investigate the MR characteristics of familial non-compaction myocardium(INVM), a rare disease, with correlation with findings on echocardiogram and CT.

The diagnosis of non-compaction left ventricular myocardium for the proband, a currently 10 years old female, was established by prenatal ultrasound at 30 week’s gestation, MRI at 2 months of age. Subsequently her 30 family members were evaluated. Among them, 7 cases (7 to 59 years old) underwent both MRI and echocardiography examination while 2 cases underwent contrast-enhanced MDCT as well. MR examinations were conducted on a 1.5 T Sonata MR scanner. True Fisp (TR/TE/Tip: 49.5ms/1.6ms/65°) short Axis and four-chamber view cine images were acquired for morphological and ventricular function assessment. Perfusion and delayed viability images were acquired for evaluation of potential myocardial fibrosis. Echocardiogram was obtained from both short axis and four-chamber view. Ratios of non-compacted vs compacted myocardium were measured on both MRI and echocardiogram.

5/7 family members including 3 asymptomatic adults had imaging evidence of noncompaction confirmed on both MRI and echocardiogram. One patient had suspicious but non-inclusive evidence while one patient was normal. Among the affected patients, 2 cases were confirmed on contrast-enhanced MDCT images. On all affected patients, INVM on MRI was characteristically demonstrated as a 2 layer structure with a compacted, thin epicardial band and a much thicker, noncompacted endocardial layer of trabecular meshwork with deep intertrabecular recesses filled by direct blood flow from the ventricular cavity. A maximum end systolic ratio of noncompacted layer to compacted layers from MRI measurement (2.27±0.35) was > 2 on all affected case (5/7) with good correlation to the ratio derived from the measurement on echocardiogram (2.28±0.30, R=0.92). There were no abnormal myocardial perfusion or delayed enhancement shown on MR images.

MRI showed good correlation to echocardiogram and MDCT in diagnosis of INVM and is a powerful modality by means of comprehensive assessment of characteristic morphology, function and perfusion in INVM.