Results
General data-related indicators are shown in Table 1. These indicators were found to have no significant effect on the flow of vascular grafts.
In this study, all patients clearly showed the IMA lumen and flow spectrum (100%) at the fourth intercostal space next to the sternum. The preoperative IMA flow spectrum showed systolic dominance, and the RI was high (Fig. 1a). Luminal diameter of postoperative IMA was wider than that of preoperative IMA. The postoperative PSV and PDV of IMA were significantly increased. The postoperative RI of IMA was reduced. The postoperative dVIT and dVITF of IMA were significantly increased (Table 2). Indicators of left ventricular function (such as EDV and SV) and blood flow between patients on- and off-pump during CABG have no significant difference (P > 0.05, Table 3).
Logistic regression analysis showed that the angle of the IMA and left subclavian artery was negatively correlated with the intraoperative vascular graft flow (= −1.88 × Angle + 344.13, P = 0.00, R2 = 0.23, Fig. 2). The vascular graft flow in at 1 week after surgery was significantly higher than the intraoperative vascular graft flow (P = 0.00, Table 4). All patients showed clinical improvement after surgery, but there was no significant difference in left ventricular function indicators.