Comparison of outcomes between off-pump versus on-pump coronary artery bypass surgery in elderly patients: a meta-analysis

Off-pump versus on-pump coronary artery bypass grafting in elderly patients at 30 days: a propensity score matching study

BACKGROUND

Elderly patients are at increased risk of perioperative morbidity and mortality after conventional on-pump coronary artery bypass grafting (ONCABG). This study was to determine whether such high-risk population would benefit from off-pump coronary artery bypass grafting (OPCABG).

METHODS

A retrospective analysis was performed on patients aged 65 years or older who underwent isolated coronary artery bypass grafting for the first time in Wuhan Union Hospital from January 2015 to January 2021. We used propensity score matching to adjust for differences in baseline characteristics between the ONCABG and OPCABG groups. Morbidity and mortality within 30 days after surgery were compared between the two groups. All operations were performed by experienced cardiac surgeons.

RESULTS

A total of 511 patients (ONCABG 202, OPCABG 309) were included. After 1:1 matching, the baseline characteristics of the two groups were comparable (ONCABG 173, OPCABG 173). The OPCABG group had higher rate of incomplete revascularization (13.9% vs. 6.9%; P = .035) than the ONCABG group. However, OPCABG reduced the risk of postoperative renal insufficiency (15.0% vs. 30.1%; P = .001) and reoperation for bleeding (0.0% vs. 3.5%; P = .030). There were no significant differences in early postoperative mortality, myocardial infarction, stroke, and other outcomes between the two groups.

CONCLUSIONS

OPCABG is an alternative revascularization method for elderly patients. It reduces the risk of early postoperative renal insufficiency and reoperation for bleeding.

A systematic review and meta-analysis of randomized controlled studies comparing off-pump versus on-pump coronary artery bypass grafting in the elderly

AIM

Comparison of short and mid-term outcomes between off-pump CABG (OPCAB) and on-pump CABG (ONCAB) in patients older than 65 throughout a meta-analysis of randomized clinical trials (RCTs).

EVIDENCE ACQUISITION

A literature search was conducted using 3 databases. RCTs reporting mortality outcomes of OPCAB versus ONCAB among the elderly were included. Data on myocardial infarction, stroke, re-revascularization, renal failure and composite endpoints after CABG were also collected. Random effects models were used to compute statistical combined measures and 95% confidence intervals (CI).

EVIDENCE SYNTHESIS

Five RCTs encompassing 6221 patients were included (3105 OPCAB and 3116 ONCAB). There were no significant differences on mid-term mortality (pooled HR: 1.02, 95%CI: 0.89-1.17, p=0.80) and composite endpoint incidence (pooled HR: 0.98, 95%CI: 0.88-1.09, p=0.72) between OPCAB and ONCAB. At 30-day, there were no differences in mortality, myocardial infarction, stroke and renal complications. The need for early re-revascularization was significantly higher in OPCAB (pooled OR: 3.22, 95%CI: 1.28-8.09, p=0.01), with a higher percentage of incomplete revascularization being reported for OPCAB in trials included in this pooled result (34% in OPCAB vs 29% in ONCAB, p<0.01).

CONCLUSIONS

Data from RCTs in elderly patients showed that OPCAB and ONCAB provide similar mid-term results. OPCAB was associated with a higher risk of early rerevascularization. As CABG on the elderly is still insufficiently explored, further RCTs, specifically designed targeting this population, are needed to establish a better CABG strategy for these patients.

Effect of Age on Clinical Outcomes Following On-/Off-Pump Coronary Artery Bypass: Meta-Analysis and Meta-Regression

Objective

There is currently much debate about which patients would benefit more after on- or off-pump coronary artery bypass grafting (CABG). The aim of this meta-analysis and meta-regression is to investigate the effect of age on short-term clinical outcomes after these approaches.

Methods

To identify potential studies, systematic searches were carried out in the Excerpta Medica dataBASE (EMBASE), PubMed, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL). The search strategy included the key concepts of “cardiopulmonary bypass” AND “coronary artery bypass grafting” AND “off pump” OR “on pump”. This was followed by a meta-analysis and meta-regression investigating the effect of age on the incidences of stroke, myocardial infarction (MI), and mortality.

Results

Thirty-seven studies including 15,324 participants were analysed. Overall, there was a significant odds reduction for patients receiving off-pump CABG suffering a stroke (odds ratio [OR] 0.770, 95% confidence intervals [CI] 0.594, 0.998, P=0.048); however, when patients were subdivided according to different age bands, this difference disappeared. There were also no significant differences in the odds of mortality (OR 0.876, 95% CI 0.703, 1.093, P=0.241) or MI (OR 0.937, 95% CI 0.795, 1.105, P=0.439). Meta-regression analysis revealed no significant relationship between age and stroke (P=0.652), age and mortality (P=548), and age and MI (P=0.464).

Conclusion

Patients undergoing CABG are becoming older and may suffer from multiple comorbidities increasing their risk profile. However, with respect to short-term clinical outcomes, the patient’s age does not help in determining whether off- or on-pump is superior.