Left ventricular non-compaction cardiomyopathy in children: Characterisation of clinical status using tissue Doppler-derived indices of left ventricular diastolic relaxation

Background: Left ventricular non-compaction (LVNC) may manifest an undulating phenotype ranging from dilated to hypertrophic appearance. It is unknown whether tissue Doppler (TD) velocities can predict adverse clinical outcomes including death and need for transplantation in children with LVNC. Methods and results: 56 children (median age 4.5 years, median follow-up 26 months) with LVNC evaluated at one hospital from January 1999 to May 2004 were compared with 56 age/sex-matched controls. Children with LVNC had significantly decreased early diastolic TD velocities (Ea) at the lateral mitral (11.0 vs 17.0 cm/s) and septal (8.9 vs 11.0 cm/s) annuli compared with normal controls (p<0.001 for each comparison). Using receiver operator characteristic curves, the lateral mitral Ea velocity proved the most sensitive and specific predictor for meeting the primary end point (PEP) at 1 year after diagnosis (area under the curve=0.888, SE=0.048, 95% CI 0.775 to 0.956). A lateral mitral Ea cut-off velocity of 7.8 cm/s had a sensitivity of 87% and a specificity of 79% for the PEP. Freedom from death or transplantation was 85% at 1 year and 77% at 2 years. Conclusions: TD velocities are significantly reduced in patients with LVNC compared with normal controls. Reduced lateral mitral Ea velocity helps predict children with LVNC who are at risk of adverse clinical outcomes including death and need for cardiac transplantation.