Abstract 15662: Tissue Characterization by Integrated Backscatter and Its Relationship with Longitudinal Deformation and Diastolic Filling Properties in Heart Failure with Normal Ejection Fraction
Background: Patients with heart failure but normal ejection fraction (HFnEF) show evidence of increased myocardial collagen turnover which causes increased ventricular stiffness. Ultrasonic integrated backscatter (IB), derived by 2D echocardiography, provides information on myocardial reflectivity, which is considered a surrogate for the amount of fibrosis of the left ventricle (LV).
Objectives: To evaluate the relationship between myocardial reflectivity by IB, longitudinal systolic deformation of the LV by speckle tracking echocardiography, and degree of diastolic dysfunction in patients with HFnEF.
Methods: We studied 27 patients with HFnEF, 24 patients with HF and low ejection fraction (systolic HF [SHF]), and 25 normal controls. 2-D speckle tracking was applied to measure longitudinal strain in apical views. Diastolic function was assessed by Tissue Doppler-derived early diastolic velocity (E'), and E/E' ratio. The mean value of calibrated IB of the anteroseptal and posterior wall, from the parasternal long-axis view, was used to estimate myocardial ultrasound reflectivity.
Results: Global longitudinal strain (GLS) was significantly lower in HFnEF patients (-14.4±3.6%) than in controls (-21.2±3.2%; P<0.0001), and it was further depressed in SHF patients (-8.3±2.9%; P<0.001 vs HFnEF). E' velocity was lower (HFnEF: 6.1±1.3, SHF: 5.6±1.7, Controls: 14.1±3.4 cm/s, P<0.0001), and E/E' ratio was higher (HFnEF: 15.2±5.7, SHF: 14.7±5.9, Controls: 5.9±1.3, P<0.0001), in both HF groups than in controls, without significant differences between HF groups. HF groups also showed increased myocardial reflectivity, as evidenced by lower calibrated IB, than controls (-16.9±5.7 dB vs -24.6±6.1 dB, P<0.0001), without significant differences between HF groups (HFnEF -18.2±5.1 dB, SHF -15.4±6.3 dB). In the whole population, myocardial reflectivity was correlated with GLS (r=0.60, P<0.0001), E' velocity (r=-0.56, P<0.0001), E/E' ratio (r=0.37, P<0.01).
Conclusions: Patients with HFnEF have subclinical changes of LV structure, as evidenced by increased myocardial reflectivity, that are related to the degree of longitudinal systolic dysfunction and to diastolic abnormalities.
- © 2010 by American Heart Association, Inc.