Off-pump vs. on-pump bypass surgery grafting in diabetic patients with three-vessel disease: a propensity score matching study

Background Controversy exists regarding the advantages and risks of off-pump vs. on-pump coronary artery bypass grafting (CABG) for patients with diabetes. We therefore compare the early clinical outcomes of off-pump vs. on-pump procedures for diabetic patients with three-vessel disease. Materials and methods We conducted a retrospective analysis of clinical data obtained from 548 diabetic patients with three-vessel coronary artery disease who underwent isolated CABG between January 2016 and June 2020. To adjust the differences of baseline characteristics between the off-pump CABG (OPCAB) and on-pump CABG (ONCAB) groups, propensity score matching (PSM) was used. Following 1:1 matching, we selected 187 pairs of patients for further comparison of outcomes within the first 30 days after surgery. Results The preoperative characteristics of the patients between the two groups were clinically comparable after PSM. The OPCAB group exhibited a significantly higher incidence of incomplete revascularization (27.3% vs. 14.4%; P = 0.002) compared with the ONCAB group. No differences were seen in mortality within 30 days between the matched groups (1.1% vs. 3.7%; P = 0.174). Notably, the OPCAB group had a lower risk of respiratory failure or infection (2.1% vs. 7.0%; P = 0.025), less postoperative stroke (1.1% vs. 4.8%; P = 0.032), and reduced postoperative ventilator assistance time (35.8 ± 33.7 vs. 50.9 ± 64.8; P = 0.005). Conclusion OPCAB in diabetic patients with three-vessel disease is a safe procedure with reduced early stroke and respiratory complications and similar mortality rate, myocardial infarction, and renal failure requiring dialysis to conventional on-pump revascularization.


Supplementary Data
The variables are defined as follows 1.1 Hypertension was defined as systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg were measured at least twice in the resting state or needed to take blood pressure lowering drugs to maintain blood pressure in the normal range, and secondary hypertension was excluded [1].The vascular ultrasonography or vascular CTA examination reported the stenosis area of the artery cross-sectional area exceeds 50% as stenosis.

Atrial fibrillation
The diagnosis of atrial fibrillation is based on the electrocardiogram and physical examination.
The number of coronary artery lesions and the location of coronary artery lesions were determined according to the results of coronary angiography within 6 months.Coronary arteries with more than 50% stenosis are considered diseased vessels and isolated left main disease was identified as 2-vessel disease.Left anterior descending, left circumflex, and right coronary artery branch lesions were also included in these three artery lesions.

Preoperative left ventricular ejection fraction (LVEF) and left ventricular end-diastolic diameter (LVEDD)
The data were obtained from outpatient or preoperative echocardiography within 30 days before the operation.

Postoperative LVEF and LVEDD
The data were obtained according to the results of the postoperative in-hospital echocardiography.
1.10.Emergency surgery CABG was performed within 24 hours of hospitalization or emergency CABG due to acute myocardial infarction and cardiac catheterization complications.
1.11.Postoperative ventilator assistance and ICU time were calculated according to the nursing record sheet and doctor order sheet.
1.12.Incomplete revascularization is defined as any coronary artery mentioned in patient's coronary angiography with significant lesions (>50%) that was not revascularized.

Stroke
A new acute focal neurological deficit thought to be of vascular origin with signs or symptoms lasting longer than 24 hours.Strokes were confirmed by a neurologist based on clinical manifestations combined with brain CT and (or) magnetic resonance examination results.

Postoperative myocardial infarction
The actual value of myocardial enzymes in postoperative biochemical detection is higher than 10 times the 99th percentile of the normal distribution of the normal reference value and accompanied by one of the following conditions [4]: (1) The ECG has new left bundle branch block; (2) New graft occlusion or new native coronary artery occlusion on angiography; (3) Imaging evidence of new loss of viable myocardium or new regional wall motion abnormalities.
(1)5.Postoperative low cardiac output syndrome (LCOS)Postoperative LCOS is diagnosed when at least one of the following conditions[5]:(1)The patient needs primary care in the operating room or intensive care unit due to hemodynamic instability.Intraarterial balloon pump (IABP) to end cardiopulmonary bypass or intensive care unit; (2) patients need two or more vasopressors (dopamine, dobutamine, epinephrine, norepinephrine, isoproterenol) to maintain systolic blood pressure greater than 90 mmHg and cardiac output greater than 2.2 L• min• m2.Repeat thoracotomy due to hemorrhageThe postoperative drainage volume exceeds 200ml per hour and lasts for more than 3 hours, blood pressure and hemoglobin levels continue to decline, and surgical intervention is required to open the chest to stop bleeding.1.20.Sternal infectionDiagnosis of sternal infection is based on physical examination, imaging, and bacterial culture