Advantage of Off-pump CABG with Regards to Adverse Cerebrovascular Events after Myocardial Revascularization

Background: Various trials on outcome after myocardial revascularization did not show a significant difference between on-pump (ONCAB) and off-pump (OPCAB) CABG regarding composite outcome of adverse cerebrovascular events (CVE), i.e., postoperative stroke. There is an indication that OPCAB presents with lower rates of event-free survival than ONCAB.

Methods: We retrospectively analyzed 5,239 consecutive patients who underwent CABG at our institution between August 2012 and January 2023 for postoperative TIA, minor- or major stroke. We formed three groups according to the type of procedure (ONCAB group: n = 2,698 [51.5%]; Beating Heart [BH] group: n = 230 [4.4%]; OPCAB group: n = 2,311 [44.1%]) and compared with regards to adverse cerebrovascular events.

Results: We observed 113 (2.16%) cases of adverse cerebrovascular events after CABG (n = 34 [0.6%] cases of TIA; n = 20 [0.4%] cases of minor stroke; and n = 59 [1.1%] cases of major stroke). BMI ≥ 30, history of peripheral arterial disease, history of stroke or TIA, history of arterial hypertension, history of insulin dependent diabetes, LVEF ≤ 35%, type of procedure, emergent revascularization, and conversion to ONCAB-BH were significantly related to incidence of a postoperative stroke. After direct comparison of ONCAB to OPCAB there was a significant difference in incidence of CVE as well as major stroke within 30 days of surgery (n = 69 [2.56%] ONCAB vs. n = 24 [1.04%] OPCAB, p ≤ 0.001; n = 38 [1.41%] ONCAB vs. n = 13 [0.56%] OPCAB, p = 0.003). ONCAB vs. BH (n = 69 [2.56%] ONCAB vs. n = 20 [8.70%] BH, p ≤ 0.001; n = 38 [1.41%] ONCAB vs. n = 12 [5.22%] BH, p ≤ 0.001) and OPCAB vs. BH (n = 24 [1.04%] OPCAB vs. n = 20 [8.70%] BH, p ≤ 0.001; n = 13 [0.56%] OPCAB vs. n = 12 [5.22%] BH, p ≤ 0.001) presented with a significant difference in incidence. Patients undergoing OPCAB were at a lower risk for major stroke compared with the ONCAB group (OR = 0.33; CI: 0.18–0.60 versus OR = 1.44; CI: 0.87–2.34). Patients operated with ONCAB-BH were at an even higher risk (OR = 5.35; CI: 2.8–10.18). For conversion from OPCAB to ONCAB or BH odds ratio was 3.44 (CI: 1.23–9.66).

Conclusion: Our data shows that off-pump CABG may be superior to on-pump CABG with regards to risk of postoperative stroke after all. Conversion of the surgery to ONCAB or BH is associated with a 3-fold increase in risk for major stroke.