Abstract 705: The Difference in Left Ventricular Twisting Behavior Between Patients With Hypertensive Heart Disease and Hypertrophic Cardiomyopathy
(Background) Left ventricular (LV) untwisting behavior is a novel index of LV diastolic function since it is a powerful determinant of LV diastolic suction. The LV of patients with hypertrophic cardiomyopathy (HCM) and hypertensive heart disease (HHD) has diastolic dysfunction despite normal systolic function. However, the role of untwisting behavior in HCM and HHD in the pathophysiology of diastolic dysfunction is unknown. The aim of this study was to investigate the difference of LV twisting behavior between patients with HCM and HHD.
(Methods) Forty-four patients with HCM (mean age, 63+/−15 y, 34 males), 30 patients with HHD (mean age, 62+/−12 y, 20 males), and 20 age and sex-matched control subjects were evaluated. After a standard echocardiographic examination, LV twist and twisting velocity profiles from apical and basal short-axis images were analyzed using two-dimensional speckle tracking imaging. All temporal parameters were normalized by R-R intervals.
(Results) LV diastolic and systolic dimensions, and ejection fraction were not significantly different among the groups. LV mass index and early diastolic mitral annular velocity were not significantly different between the HCM and HHD groups. The peak torsion in the HCM and HHD groups was significantly greater than that in the control group (Table⇓). The peak untwisting velocity in the HCM group was comparable to that in the control group. However, when the peak untwisting velocity was corrected by peak torsion, the value in the HCM group was significantly decreased compared with that in the HHD and control groups. The time to peak untwisting velocity from aortic valve closure in the HCM group was significantly longer than that in the HHD and control groups.
(Conclusion) These results suggest that enhanced peak torsion in HCM might compensate for untwisting behavior, but this mechanism fails to fully compensate for untwisting behavior compared with HHD.