Abstract 2938: Decrease in Endocardial Radial Strain Precedes Global Left Ventricular Dysfunction in Patients With Hypertension.
Background: Recent studies have reported that endocardial radial strain was approximately two fold greater than epicardial strain in normal subjects. Hypertension is a major cause of myocardial dysfunction and heart failure, but the difference between endocardial and epicardial radial strain in patients with hypertension is unknown. Two-dimensional speckle tracking echocardiography is a novel echocardiographic method that enables angle-independent assessment. Aim: The aim of this study was to evaluate the difference between radial strain in endocardial and epicardial segments in hypertensive patients.
Method: This study enrolled 37 patients with hypertension (H group, age 63±12years, 24men) and 17 sex- and age-matched normal subjects (N group, age 61±7 years, 9 men). Conventional echocardiography was performed by a Vivid 7 dimension (GE). Endocardial and epicardial radial strains were calculated from the left ventricular (LV) short axis view at the papillary muscle level using custom software (EchoPAC (GE)).
Results: There were no significant differences in LV diastolic dimension (47±5 mm vs. 48±4 mm), LV systolic dimension (29±4 mm vs. 29±4 mm), LV ejection fraction (65±9% vs. 67±6%) and fractional shortening (38±5% vs. 39±5%) between the H and N group. LV mass index (LVMI) in the H group was significantly greater than in the N group (109±33g/m2 vs. 90±22g/m2, P<0.05). Global radial strain including endocardium and epicardium were not significantly different between the H and N group (59±20% vs. 62±17%). However, endocardial radial strain in the H group was significantly less than in the N group (48±24% vs. 62±15%, P=0.03), whereas there was no significant difference in epicardial radial strain between the two groups (38±16% vs. 28±10%). The ratio of endocardial to epicardial radial strain (Endo/Epi ratio) in the H group was significantly smaller than in the N group (1.5±1.1 vs. 2.4±1.1, P<0.01). There were significant correlations between End/Epi ratio and LVMI (r=-0.33, P<0.05), and relative wall thickness (r=-0.43, P<0.01).
Conclusion: A decrease in endocardial radial strain precedes global LV dysfunction in patients with hypertension.