Abstract 15149: Aortic Total Clamp Increases Post Coronary Artery Bypass Grafting Stroke: A Multinomial Multifactor Model

Abstract

Introduction: We performed a multinomial multifactor propensity-score based analysis on stroke in patients undergoing CABG. The unique model allowed us to test all the potential technical risk related to aortic manipulation alone or in combination. Methods: The study population included 16,255 consecutive patients undergoing isolated CABG between 1997 and 2017. Patients were divided into 7 groups: 1) No Proximal Anastomoses-Off-pump (NPA-OFF) group, 2) Side Biting Clamp-Off-pump (SBCL-OFF) group, 3) No Proximal Anastomoses-Beating Heart-On-Pump (NPA-BH-ON) group, 4) Side Biting Clamp-Beating Heart-On-Pump (SBCL-BH-ON) group, 5) No Proximal Anastomoses-Aortic Total Clamp-On-pump (NPA-ATC-ON) group, 6) Aortic Total Clamp-On-pump (ATC-ON) group, 7) Aortic Total Clamp-Side Biting Clamp-On-pump (ATC-SBCL-ON) group. The main end-point was the incidence of postoperative stroke within 30 days of the procedure. Statistical significance was set for p-values< 0.05 (*). Results: The optimal balance with the balance table, effect size plot and Q-Q plot, allowed us to conclude that the groups were similar to support causal estimation of the treatment estimand. As shown in Figure 1, there was no difference between a total no-touch (NPA-OFF group) vs. the same technique on pump (NPA-BH-ON group, p>0.05) and or adding a side biting clamp to these two procedures (SBCL-OFF group and SBCL-BH-ON group, both p>0.05). All procedures including the use of a total clamp (NPA-ATC-ON, ATC-ON and ATC-SBCL-ON groups) had a significantly higher incidence of stroke (all p<0.001). However, the latter procedures did not show difference between them (p>0.05). Conclusions: Aortic total clamp is the main factor increasing the incidence of stroke. In contrast, the use of side biting partial clamping, off-pump techniques or cardiopulmonary bypass without aortic clamp and cardioplegic arrest, does not affect the incidence of stroke.