ObjectiveTo investigate the early clinical efficacy of minimally invasive cardiac surgery coronary artery bypass grafting (MICS CABG) via left intercostal small incision for multivessel coronary artery disease. MethodsThe patients who received off-pump CABG in the Central China Fuwai Hospital of Zhengzhou University from June 2021 to June 2023 were enrolled. Patients were divided into two groups according to the operative technique used, including a traditional midline sternotomy group and a left intercostal small incision group. The clinical data of the two groups were compared. ResultsA total of 143 patients were enrolled, including 70 patients in the traditional midline sternotomy group and 73 patients in the left intercostal small incision group. The age of the patients in the left intercostal small incision group and the traditional midline sternotomy group was (63.8±8.0) years and (63.0±7.8) years, respectively; the proportions of males were 69.9% and 74.3%, respectively. The differences were not statistically significant (all P>0.05). All patients in the two groups successfully completed the operation, and no patients in the left intercostal small incision group were converted to thoracotomy. The patients in the left intercostal small incision group showed less postoperative drainage within postoperative 24 hours [(239.4±177.7) mL vs. (338.0±151.9) mL, P<0.001], lower perioperative blood transfusion rate [32.9% (24/73) vs. 51.4% (36/70), P=0.028], higher postoperative myoglobin level within postoperative 24 hours [366.1 (247.9, 513.0) ng/mL vs. 220.8 (147.2, 314.9) ng/mL, P<0.001], shorter intensive care unit stay [45.5 (31.5, 67.5) h vs. 68.0 (46.0, 78.5) h, P=0.001] and postoperative hospital stay [(10.8±4.0) d vs. (13.1±5.3) d, P=0.028] compared to the traditional midline sternotomy group. There was no significant difference in the incidence of major adverse cardiac and cerebrovascular event between the two groups [2.7% (2/73) vs. 2.9% (2/70), P=1.000]. ConclusionCompared to the full median sternotomy, MICS CABG leads to a good clinical result with smaller trauma, faster overall recovery, and less perioperative blood transfusion.