Vascular Endothelial Dysfunction during Cardiac Surgery: On-Pump versus Off-Pump Coronary Surgery

Area of Science:

• Cardiovascular Science
• Vascular Biology
• Surgical Research

Background:

• Cardiac surgery can induce ischemia and systemic inflammatory response, compromising vascular barrier function.
• The endothelial glycocalyx (EG) and endothelial cells maintain vascular integrity.
• Endothelial cell activation and gap junction integrity are crucial for barrier function.

Purpose of the Study:

• To assess microvascular barrier disruption by measuring endothelial cell activation parameters.
• To investigate the role of angiopoietins in endothelial gap junctions during cardiac surgery.
• To compare endothelial activation in on-pump versus off-pump cardiac surgery patients.

Main Methods:

• 30 patients undergoing coronary artery bypass surgery were divided into conventional (CCAB) and off-pump (OPCAB) groups.
• Blood samples were collected to measure angiopoietin-1 (Ang-1), angiopoietin-2 (Ang-2), VE-cadherin, and endocan.
• Measurements were taken at various time points to track changes in these biomarkers.

Main Results:

• All measured parameters (Ang-1, Ang-2, VE-cadherin, endocan) significantly increased in both groups post-surgery.
• Conventional coronary artery bypass surgery (CCAB) showed quantitatively greater increases in all parameters compared to off-pump coronary artery bypass grafting (OPCAB).
• Maximal increases observed: Ang-1 (+220% CCAB, +166% OPCAB), Ang-2 (+150% CCAB, +20% OPCAB), VE-cadherin (+87% CCAB, +66% OPCAB), endocan (+323% CCAB, +72% OPCAB).

Conclusions:

• Major cardiac surgery activates endothelial cells and disrupts cell-cell contacts.
• Angiopoietin-1 and endocan may play a counterregulatory role in endothelial activation.
• Greater endothelial activation in CCAB suggests a link between ischemia/reperfusion and barrier disruption.