Intraaortic filtration captures particulate debris in OPCAB cases using anastomotic devices

Studies associate atheroemboli with neurologic complications following cardiac surgery. The International Council of Emboli Management (ICEM) has demonstrated debris is captured when intraaortic filtration is employed during cardiac surgery. Particulate debris has been extracted from over 98% of ICEM patients and fibrous atheroma from 73%. Anastomotic device use may reduce aortic manipulation, minimizing debris. This study compares particulate capture among three patient groups: Cohort 1 (n = 745) patients receiving on-pump CABG-only procedures; Cohort 2 (n = 24) patients receiving off-pump CABG-only procedures with conventional anastomoses; Cohort 3 (n = 10) patients receiving off-pump CABG-only procedures with automatic proximal anastomoses.

The intraaortic filter was placed distal to anastomoses, and proximal to the innominate artery. Upon removal, filters were fixed in formalin and shipped to a core lab (Stanford, CA). Demographic, procedural, and outcomes data were collected in the ICEM Registry.

Of the 745 patients receiving stopped-heart CABG, complete data on preoperative risk factors was reported for 673 patients. At least 19 patients reported complete data in Cohort 2, and 10 reported in Cohort 3. One adverse outcome, a death, occurred in the 24 off-pump patients reporting (4.2%). Histologic analyses showing the number of filters successfully extracting particles, the number of particles and total particulate surface area per filter, and the ranges are shown in below. Histologic Finding Cohort 1 Cohort 2 Cohort 3 Filters with particles 98% 100% 100% Mean # of particles 8.5 9.6 5.6 Range # of particles 0-76 1-29 2-13 Mean surface area (mm2) 11.8 18.4 6.1 Range surface area (mm2) 0-171 0.5-61 0.2-14

These data clearly suggest that there is no difference between the amount of particulate debris generated in OPCAB cases versus CPB cases. In OPCAB cases where an anastomosis device was used without a partial clamp, particulate debris may be reduced but not eliminated. These findings may demonstrate the importance of aortic manipulation, particularly clamping, as a source of particulate material in cardiac surgery. However, more study needs to be done to confirm these findings with a larger number of patients.