Off-Pump Coronary Artery Bypass Leads to a Regional Hypercoagulable State Not Detectable Using Systemic Markers

Area of Science:

• Cardiovascular Surgery
• Hematology
• Biochemistry

Background:

• Off-pump coronary artery bypass grafting (OPCAB) is theorized to induce hypercoagulability, but evidence remains inconclusive.
• Previous studies have not definitively documented a hypercoagulable state following OPCAB.

Purpose of the Study:

• To investigate the hypothesis that OPCAB increases the risk of a regional hypercoagulable state.
• To compare coagulation activation markers between OPCAB and on-pump CABG.

Main Methods:

• Transcardiac gradients of F1.2, FXIIa, myoglobin, IL-6, and IL-8 were measured post-CABG (off-pump N=69; on-pump N=35).
• Platelet-derived microparticles, platelet function, myocardial pH, and SVG flow were assessed.
• Endothelial integrity and graft patency were evaluated.

Main Results:

• OPCAB demonstrated significantly higher transcardiac levels of F1.2, FXIIa, microparticles, IL-6, and IL-8 compared to on-pump CABG.
• Myoglobin release was greater after OPCAB, correlating with regional pH changes and F1.2 release.
• Systemic markers showed less change post-OPCAB, while SVG flow was reduced, but endothelial integrity and graft patency remained similar.

Conclusions:

• Transcardiac assays revealed enhanced regional coagulation after OPCAB compared to on-pump CABG.
• These findings suggest OPCAB may necessitate additional antithrombotic therapies to manage localized hypercoagulability.
• Further research is required to confirm these results and guide clinical practice.