Abstract 965: Quantification of Global Left Ventricular Relaxation and Its Coupling to Systolic Contraction in Patients with Myocardial Infarction by Speckle Tracking Global Strain and Strain Rate Imaging
Background: Quantification of global left ventricular (LV) function is clinically important in patients with myocardial infarction (MI). We tested the hypothesis that speckle tracking global strain and strain rate imaging can quantify global left ventricular relaxation, systolic contraction, and their coupling in patients with MI.
Methods: To quantify global LV longitudinal and circumferential function, forty-seven patients with old MI (OMI: Ejection fraction 43 ± 15 %) and thirty-one age matched normal controls (Control: Ejection fraction 64 ± 5 %) were studied with speckle tracking strain and strain rate imaging. Global peak systolic strain (PSS) and peak relaxation rate (PRR) were analyzed from apical 4-, 2-, long axis, and mid-ventricular short axis views (EchoPAC, GE Electronic). LV ejection fraction was assessed by biplane Simpson’s rule.
Result: Both longitudinal and circumferential PSS strongly correlated to ejection fraction with linear regression (y = −0.028 x = 0.15, r = 0.77* and y = −0.023x = 0.16, r = 0.84*, *P < 0.05) in OMI. Both longitudinal and circumferential PRR significantly correlated to PSS with linear regression (y = −0.044 x = 0.17, r = 0.74* and y = −0.038 x= 0.29, r = 0.66*, *P < 0.05). Furthermore, there were strong correlations between PSS and PRR with exponential regression both in longitudinal and circumferential directions (y = 0.29e−0.068x, r = 0.80* and y = 0.33e−0.065x, r = 0.78*, *P < 0.05) all the subjects from Control to OMI.
Conclusions: Speckle tracking global strain and strain rate imaging quantified global left ventricular relaxation, systolic contraction, and their rigid coupling in patients with OMI.