Abstract 2212: Longitudinal Displacement of Mitral Annulus Shows Early Recovery Following Induction of Beta-Blockade in Patients with Chronic Heart Failure
Objectives: LV global systolic function, e.g. LV ejection fraction (EF), is gradually improved by beta-blocker therapy in patients with chronic heart failure. Tissue Doppler imaging is one of the most appropriate ultrasound technologies capable of detecting regional LV dysfunction using displacement and deformation indexes. We attempted to explore echo-Doppler indexes of LV function that change sooner and more sensitively than LVEF following beta-blocker therapy.
Methods: Echocardiography was performed before and 2, 6, and 12 months after initiation of target dose beta-blocker therapy (Bisoprolol 2.5~10mg) in 32 patients with clinically stable chronic heart failure (21 males and 11 females; mean age, 57±15 years). Apical two and four-chamber views of tissue Doppler images were acquired to determine longitudinal mitral annulus displacement at 4 points of the basal anterior, inferior, lateral and septum walls. Peak systolic strain in the radial direction was measured at the anterior and posterior walls in the short-axis view. The time to peak myocardial sustained systolic velocity during the ejection phase (Ts) in 12 segments was provided for the determination of standard deviation of Ts (Ts-SD) as an index of dyssynchrony.
Results (table⇓): LVEF improved gradually after the induction of beta-blocker therapy. In contrast, longitudinal displacement improved fully even in 2 months. Improvements in the radial peak systolic strain and Ts-SD were gradual. Multiple step-wise regression analysis showed that the increase in EF is related to the changes in longitudinal displacement and radial systolic strain (r=0.70, p<0.01) but not to the Ts-SD.
Conclusions: Myocardial contraction in the longitudinal direction appeared to improve sooner than that in the radial direction and dyssynchrony following beta-blocker therapy. Because LVEF is determined as an integration of myocardial function in the longitudinal and radial directions, its recovery occurs gradually.