Operative strategies to reduce cerebral embolic events during on- and off-pump coronary artery bypass surgery: A stratified, prospective randomized trial (original) (raw)

Objective: To determine the impact of different aortic clamping strategies on the incidence of cerebral embolic events during coronary artery bypass grafting (CABG). Methods: Between 2012 and 2015, 142 patients with low-grade aortic disease (epiaortic ultrasound grade I/II) undergoing primary isolated CABG were studied. Those undergoing off-pump CABG were randomized to a partial clamp (n ¼ 36) or clampless facilitating device (CFD; n ¼ 36) strategy. Those undergoing onpump CABG were randomized to a single-clamp (n ¼ 34) or double-clamp (n ¼ 36) strategy. Transcranial Doppler ultrasonography (TCD) was performed to identify high-intensity transient signals (HITS) in the middle cerebral arteries during periods of aortic manipulation. Neurocognitive testing was performed at baseline and 30-days postoperatively. The primary endpoint was total number of HITS detected by TCD. Groups were compared using the Mann-Whitney U test. Results: In the off-pump group, the median number of total HITS were higher in the CFD subgroup (30.0; interquartile range [IQR], 22-43) compared with the partial clamp subgroup (7.0; IQR, 0-16; P<.0001). In the CFD subgroup, the median number of total HITS was significantly lower for patients with 1 CFD compared with patients with>1 CFD (12.5 [IQR, 4-19] vs 36.0 [IQR, 25-47]; P ¼ .001). In the on-pump group, the median number of total HITS was 10.0 (IQR, 3-17) in the single-clamp group, compared with 16.0 (IQR, 4-49) in the double-clamp group (P ¼ .10). There were no differences in neurocognitive outcomes across the groups. Conclusions: For patients with low-grade aortic disease, the use of CFDs was associated with an increased rate of cerebral embolic events compared with partial clamping during off-pump CABG. A single-clamp strategy during on-pump CABG did not significantly reduce embolic events compared with a doubleclamp strategy.