Abstract 14203: Speckle Tracking Analysis During Dobutamine Stress Echocardiography in Patients Undergoing Percutaneous Coronary Intervention for Chronic Total Occlusion

Abstract

Background: Dobutamine stress echocardiography (DSE) is often used as a non-invasive diagnostic modality for detection of myocardial ischemia and viability. A “biphasic response” in DSE can occur, in which contractility improves in dysfunctional segments with low dose stage and then becomes dysfunctional again at higher doses due to ischemia. We investigated if speckle tracking analysis during DSE can evaluate patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). Methods: DSE was performed one day before CTO-PCI in consecutive 30 patients (18 female, age=71±11 years). Since 27 patients had 1 vessel, and 3 patients had 2 vessel CTO lesions, total of 33 regions were analyzed. Global (GLS) and regional longitudinal strain (RLS) were calculated as an averaged value of peak longitudinal strain in the apical 4-, 2-chamber, and long axis views at baseline echo, at low-dose, at high-dose DSE, and 6 months after CTO-PCI using available software (QLAB, Philips Medical Systems). Results: CTO-PCI was successfully done in all patients. GLS and RLS were feasible in all regions. Overall, GLS (-15.5±2.8 at baseline v.s. -17.3±3.8, p<0.001) and left ventricular ejection fraction (LVEF) (56±6% v.s. 58±7%, p<0.01) significantly improved 6 months after CTO-PCI. There was also significant improvement of RLS for the obstructed CTO regions (-13.8±3.6 v.s. -16.5±4.2, p<0.005). Although in 24 patients (26 regions) with biphasic response during DSE (Figure), GLS (-15.7±2.5 v.s. -17.9±3.6, p<0.01), LVEF (54±6% v.s. 56±7%, p<0.05), and RLS (-13.8±3.5 v.s. -16.8±4.0, p<0.01) improved significantly, GLS (-14.9±4.2 v.s. -15.8±5.0, p=n.s.), LVEF (59±3% v.s. 60±3%, p=n.s.), and RLS (-13.9±4.5 v.s. -15.5±5.7, p=n.s.) didn’t change in 6 patients (7 regions) without biphasic response. Conclusion: Speckle tracking analysis is feasible during DSE. CTO-PCI may improve both global and regional cardiac functions in patients with myocardial viability.