Tei index evaluates left ventricular function changes after on-pump and off-pump coronary artery bypass surgery

摘要

Objective: To compare function recovery of left ventricle after off-pump and on-pump coronary artery bypass (OPCAB and ONCAB) using Tei index. Methods: Twenty-four patients with coronary artery disease were enrolled, twelve of which received OPCAB and the others underwent ONCAB. Left ventricular ejection fraction (LVEF), E/A ratio at mitral orifice and Tei index were measured using transthoracic echocardiography before surgery and 3-7 days, 1 month, 3 months and 6 months after surgery. Results:Tei index of both groups decreased 3-7 days after surgery, with OPCAB group's lower than ONCAB group's. The difference between pre-and post-OPCAB was significant (P < 0.01), but not for ONCAB group (P > 0.05). Tei index of ONCAB decreased more significant than that of OPCAB 1 month after surgery, there was statistical difference between 3-7 days and 1 month after surgery in ONCAB (P < 0.01). Afterwards, Tei index of the 2 groups decreased steadily with no significant difference between them at other time points. LVEF and E/A ratio decreased at first, then increased gradually, with no statistical differences between the 2 groups at all time points. Conclusion: The recovery of left ventricular function after OPCAB is earlier than ONCAB. Tei index is more sensitive than LVEF and E/A ratio in detecting cardiac function recoveries and can be considered as an accurate and simple method to evaluate left ventricular systolic and diastolic function.