Echocardiographic Characteristics Including Tissue Doppler Imaging After Enhanced External Counterpulsation Therapy

Abstract

Background: The aim of this study was to echocardiographically assess the effects of EECP (Enhanced External Counterpulsation Therapy) therapy on systolic and diastolic cardiac function. Methods: LVEF (left ventricular ejection fraction), ESV (end-systolic volume), EDV (end-diastolic volume), Sm (myocardial systolic wave), Ea (myocardial early diastolic wave), Vp (propagation velocity), E/Ea (peak early diastolic transmitral flow velocity/Ea), E/Vp and diastolic function grade were studied in twenty-five patients before and after 35 hours of EECP. Results: EECP reduced ESV and EDV and increased EF significantly (p=0.018, 0.013, 0.002, respectively) in patients with baseline LVEF≤50%, but not in patients with baseline LVEF>50%. Patients with E/Ea≥14 had a significant reduction in EDV and ESV (p=0.038 and 0.32, respectively) and an increase in LVEF (p=0.007) after EECP, whereas patients with baseline E/Ea<14 had no significant change in these parameters. Similarly, EECP significantly improved ESV, EDV and LVEF (p=0.014, 0.032, 0.027 respectively) in patients with grades II and III of diastolic dysfunction (decreased compliance) at baseline, but not in patients with normal diastolic function or grade I diastolic dysfunction (impaired relaxation). Patients with Ea<7 cm/sec prior to EECP showed significant improvement in EDV, ESV and LVEF after therapy (p=0.024, 0.015, 0.001), while patients with Ea ≥7cm/sec showed no significant change. Similarly, patients with Sm<7cm/sec prior to EECP showed significant improvement in EDV, ESV and LVEF after EECP (p=0.016, 0.017, 0.006), while patients with Sm ≥7cm/sec did not. Conclusion: These results provide new insight into the hemodynamic effectiveness and potential clinical applications of EECP.