Two-dimensional speckle tracking echocardiography for evaluating the effect of enhanced external counterpulsation on left ventricular function in elderly patients with coronary slow flow phenomenon / 中华老年医学杂志

ABSTRACT

Objective:This study aimed to evaluate the effect of enhanced external counterpulsation(EECP)on left ventricular function in elderly patients with coronary slow flow phenomenon(CSFP)using two-dimensional speckle tracking echocardiography(2D-STE).Methods:This prospective case-control study included 30 patients aged ≥60 years with no stenotic lesions in the coronary arteries but with slow blood flow phenomenon in more than one major coronary artery who were treated at the Department of Geriatrics, Qilu Hospital, Shandong University, between December 2017 and December 2018, and were divided into a medication group with 16 participants and a medication plus EECP group with 14 participants, using the numerical lottery method.Patients in the group treated with EECP received 6-week 36-h EECP therapy in addition to lifestyle modification and drug treatment.Fourteen patients with normal coronary blood flow served as the control group.Conventional echocardiography and 2D-STE were used to evaluate changes in left ventricular function in the CSF patients before and after drug treatment and EECP.Results:Compared with the control group before treatment, patients in the drug treatment group and the drug treatment plus EECP group showed a decrease in mitral annular early diastolic velocity( P<0.01), an increase in the ratio of peak mitral early diastolic blood flow velocity to the mean peak mitral annular early diastolic velocity( P<0.05), and a decrease in left ventricular longitudinal strain during systole( P<0.01), the longitudinal systolic myocardial strain rate( P<0.01)and the early diastolic longitudinal peak strain rate( P<0.01).There was no statistically significant difference in values from conventional echocardiographic parameters before and after treatment in CSF patients of the medication group(all P>0.05).In the group receiving EECP, there were statistically significant differences in pre-and post-treatment values in ventricular septal early diastolic velocity[(6.22 ± 0.64)cm/s vs.(6.69 ± 0.44)cm/s], lateral wall early diastolic velocity[(8.01±0.68)cm/s vs.(8.41±0.29)cm/s], mitral valve to mitral annulus early diastolic peak velocity ratio[(10.51±1.38) vs.(9.74±0.37)], longitudinal left ventricular systolic strain[(-16.21±0.46)% vs.(-16.80±0.48)%], left ventricular systolic longitudinal strain rate[(-1.29±0.03)s -1vs.(-1.35±0.04)s -1], and early diastolic longitudinal strain rate[(1.35±0.03)s -1vs.(1.40±0.03)s -1](t-values were -3.70、-2.74、2.23、10.25、12.30、-19.15, all P<0.05). Conclusions:2D-STE can evaluate subclinical myocardial dysfunction early and quantitatively in elderly patients with CSF, and objectively reflect changes in left ventricular function before and after clinical intervention with EECP.