Three-dimensional speckle tracking imaging to assess myocardial ischemia and left ventricular function after coronary artery bypass grafting in coronary heart disease patients

This study evaluated the effects of coronary artery bypass grafting (CABG) on myocardial ischemia and left ventricular function in patients with coronary heart disease (CHD) using three-dimensional speckle tracking imaging (3D-STI). Fifty-one CHD patients who underwent CABG were included as observation group, and 49 healthy volunteers served as controls. Sample size was determined based on power analysis (α = 0.05, β = 0.20) to detect a 5 % difference in left ventricular ejection fraction (LVEF). The basic data of the two groups of subjects were obtained, including conventional echocardiography and 3D-STI images before surgery, 30 days and 60 days after surgery. The following key echocardiographic parameters, including LVEF and end-diastolic diameter, were measured to assess myocardial function. LVEF substantially ( P < 0.05) improved from 56.34 ± 10.08 preoperatively to 61.02 ± 8.24 at 60 days postoperatively. Left ventricular end-diastolic diameter (LVEDd), left ventricular end-diastolic volume (LVEDv), and left ventricular end-systolic volume (LVESv) were improved 30 days and 60 days after the surgery versus their values before the surgery, showing statistically marked ( P < 0.05) differences. The local myocardial SLs, SrLs, and SrLe of the original ischemic segment in observation group were substantially improved 30 days and 60 days after the surgery versus those before surgery ( P < 0.05). The postoperative global peak longitudinal strain (GLS) and GLS-Avg of observation group were improved versus those before the surgery ( P < 0.05). These improvements indicate that CABG effectively restores left ventricular function and reduces myocardial ischemia in CHD patients. CABG not only effectively alleviates myocardial ischemia in patients with CHD, and promotes the recovery of left ventricular function but also improves the overall prognosis of cardiac function. 3D-STI can serve as an important tool for the objective assessment of surgical outcomes, providing strong support for clinical decision-making. 3D-STI outperformed conventional 2D-STI in detecting subtle post-CABG strain improvements, particularly in apical segments.