We analyzed 81 adults: HCM patients with LV hypertrophy (LVH+, n=38), mutation carriers without LV hypertrophy (LVH/G+, n=20), and normal control subjects (n=23). We calculated global longitudinal strain (GLS), regional peak longitudinal strain and the Echo/TDI score (combination of 3 parameters about remodeling and pulse TDI). Age, sex ratio and body surface area were not significantly different between groups. Maximal 2D wall thickness of left ventricle was 10.1±1.6mm in LVH-/G+ and not different from controls (9.9±1.2mm). We observed that LV GLS was not different in LVH-/G+ as compared to controls (–21.6%±3.2 vs –23.5%±3.3) but was reduced in HCM patients (–15.3%±4.5) although a normal ejection fraction. Interestingly, regional peak longitudinal strain was similar in LVH-/G+ and controls except antero-septo-basal segment strain that was decreased in LVH-/G+ as compared to controls (–15.6%±7.2 vs –20.0%±3.9, p=0.025). A cut-off of –16% for abnormal strain of antero-septo-basal segment identified LVH-/G+ subjects with a sensitivity of 47% and a specificity of 90%. The Echo/TDI score was different in LVH-/G+ as compared to controls (p=0.0008) and sensitivity of previous defined cut-off was 83% for identification of LVH-/G+. All LVH-/G+ subjects with abnormal regional strain, except one, had abnormal Echo/TDI score.
We observed that regional longitudinal strain, but not global strain, was significantly reduced at early stage of HCM. This tool may be useful for clinical evaluation of relatives in daily practice, but does not provide significant additional information as compared to the Echo/TDI score.