Objective: To assess the left ventricular rotation and twist in patients with hypertrophic cardiomyopathy (HCM) by 2-dimensional ultrasound speckle-tracking imaging (STI).
Methods: Two-dimensional images of left ventricule (LV) at basal and apical short-axis views were acquired in 20 patients with HCM and 20 healthy subjects to evaluate LV rotation. LV twist were defined as rate of apical LV rotation to the basal. Peak rotation (Prot) and the time to Prot in basal and apical short axis views were measured separately. Peak twist (Ptw), twist at aortic valve closure (AVCtw), twist at mitral valve opening (MVOtw), untwisting rate (Untw R), and half time of untwisting (HTU) were calculated.
Results: Compared with the control group, the value of Prot-MV, Prot-AP, Ptw, time to Ptw, AVCtw, MVOtw, and HTU significantly increased (all P < 0.05) and the Untw R significantly decreased (P < 0.05) in the HCM group. In the HCM group, time to Prot in apical view was significantly higher than that in basal view.
Conclusion: STI can noninvasively evaluate the characteristics of LV twist and rotation in patients with HCM.