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Abstract 2D strain or speckle tracking imaging; this rapidly expanding technology entails spatial and temporal tracking of adjacent naturally occurring acoustic markers or “speckles” from standard black and white echocardiographic images in 2 dimensions. Deformation is calculated on a frame-frame analysis of speckle displacement, yielding angle independent parameters of myocardial contraction, namely longitudinal strain and strain rate (long-axis images). Similarly, radial and circumferential strain or strain rate may be measured off the short-axis images. The aim of our study was to determine if HCM has distinctive patterns by 2 dimensional speckle tracking echocardiography which help differentiate it from left ventricular hypertrophy secondary to essential hypertension. We enrolled 90 subjects in our work distributed as: • HCM group: 30 patients with hypertrophic cardiomyopathy, • Hyperension group: 30 patients with essential hypertension and LVH. • Control group: 30 normal subjects forming the control group. All subjects were evaluated by history taking, clinical examination, and 12-lead ECG. Patients were subjected to conventional M-mode and 2-D transthoracic echocardiographic examination and Doppler study using standard parasternal and apical views to assess left ventricular diastolic function via transmitral mitral inflow velocities and left ventricular chamber dimensions and function. Pulsed wave tissue Doppler echocardiography was acquired at the lateral mitral annulus. Images for speckle-tracking echocardiographic analysis, currently performed offline, are obtained and recorded by using conventional 2-dimensional gray scale echocardiography during breath holding with stable electrocardiographic tracing. The following parameters show statistically significant differences between the HCM and hypertension groups: 1) Conventional M-mode Echocardiography a. The LVEDD and LVESD had significantly lower values in HCM group.(p value <0.001). b. The IVS and IVS/PWT ratio had significantly higher values in HCM group (p value<0.001)with IVS cut-off value 15mm or more and IVS/PWT ratio > 1.3 that showed a sensitivity of 80% and 63% respectively and a specificity of 56% and 100% respectively. 2) Conventional Doppler Echocardiography There was no significant difference between HCM and hypertensive group regarding transmitral inflow velocities. 3) PW tissue Doppler study at the lateral mitral annulus a. The Ea wave velocities showed significantly lower values in the HCM patients.(p value<0.001)with cut-off value 6cm/sec or less which demonstrated a sensitivity of 50% and a specificity of 94%. b. The Aa wave showed statistically significantly lower velocities in the HCM group.(p value=0.002) c. The Sa wave velocities showed significantly lower values in the HCM patients.(p value <0.001) with cut-off value 9cm/sec or less which had a sensitivity of 90% and a specificity of 65%. 4) Two Dimensional speckle tracking echocardiography a. Longitudinal strain and strain rate at the apical, mid and basal septum showed significantly lower values in the HCM group than hypertensive group.(p values <0.001 at apical septum ,0.049 at mid septum & <0.001 at basal septum) with cut-off values of systolic longitudinal strain (ε) at basal septum and mid septum were -12.8% and - 14.2% with a sensitivity of 90% and a specificity of 80% for both. b. Two patients with HCM showed paradoxical positive longitudinal strain and strain rate at apical, mid and basal septum. |