Electrocardiographic strain and endomyocardial radial strain in hypertensive patients
ABSTRACT Electrocardiographic strain pattern (ECGS) is a well-recognized marker of the presence and severity of anatomic left ventricular hypertrophy (LVH) and also has been associated with adverse prognosis in hypertensive patients. Left ventricular (LV) endomyocardial radial strain (Endo-RS) is predominant in systolic LV wall thickening compared with epimyocardial radial strain (Epi-RS) in a normal heart. However, it remains unclear whether the ratio of Endo-RS to Epi-RS alters in hypertensive patients, especially in those with ECGS.
Endo-RS and Epi-RS in 9 non-hypertensive subjects (Group A), 26 hypertensive subjects without ECGS (Group B), and 16 hypertensive subjects with ECGS (Group C) were assessed by a tissue tracking system.
Relative wall thickness, LV mass index, and voltage of SV1+RV5 were significantly greater in Group C than in both Groups A and B. Although no significant difference was seen in Epi-RS among the 3 groups, Endo-RS and the ratio of Endo-RS to Epi-RS (Endo/Epi-RS) in Group C were significantly lower than those in the other two groups. Multiple logistic regression analysis revealed that the only factor which significantly correlated with Endo/Epi-RS in the first tertile (<1.6) was the presence of ECGS (OR=9.28, p=0.01).
The appearance of ECGS significantly correlated with not only the development of LV hypertrophy but also with the attenuation of Endo-RS.
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ABSTRACT: Left ventricular (LV) remodeling in systemic arterial hypertension causes electrical conduction delay and impairs synchronous contraction, which may contribute to the development of heart failure. This study aimed to assess the change of LV mechanics in hypertension by layer-specific dyssynchrony. One hundred and twenty-one patients with primary hypertension and LV ejection fraction >50 % (mean age, 62 ± 10 years) and 31 normotensive controls (mean age, 63 ± 9 years) were prospectively included. Layer-specific dyssynchrony index (DI) was defined as standard deviation of time interval (TI) from the onset of Q wave to peak longitudinal strain obtained from 18 segments in each endocardial, myocardial, and epicardial layer. The global TI between the onset of Q wave to peak global longitudinal strain in each layer was obtained and the time difference (TD) of global TI between layers was calculated. DIs were significantly different in three layers (P P = 0.001). Layer-specific DI revealed delayed contraction in each layer and between layers in hypertensive patients, which were apparent in endocardium and between endocardium and myocardium. Increased layer-specific DIs were associated with subclinical LV dysfunction, although LV ejection fraction was preserved. These may be helpful to understand layer-specific mechanical property of LV myocardium and for early detection of subclinical impairment of myocardial function.Heart and Vessels 01/2015; DOI:10.1007/s00380-014-0626-0 · 2.11 Impact Factor